LENNOX EL196UHE High Efficiency Gas Furnace User Manual

June 9, 2024
Lennox

EL196UHE High Efficiency Gas Furnace

UNIT INFORMATION

Service Literature

Corp 1805-L1 Revised 08/2022

EL196UHE

EL196UHE SERIES UNITS

EL196UHE series units are high-efficiency gas furnaces manufactured with Lennox DuralokPlus aluminized steel clamshell-type heat exchangers, with a stainless steel condensing coil. EL196UHE units are available in heating input capacities of 30,000 to 110,000 Btuh and cooling applicationsfrom 2 through 5 tons. Refer to Engineering Handbook for proper sizing.
Units are factory equipped for use with natural gas. A kit is available for conversion to LP/Propane operation. All EL196UHE units are equipped with a hot surface ignition system. The gas valve is redundant to assure safety shutoff as required by C.S.A.
The heat exchanger, burners and manifold assembly can be removed for inspection and service. The maintenance section gives a detailed description on how this is done.
All specifications are subject to change. Procedures outlined in this manual are presented as a recommendation only and do not supersede or replace local or state codes.
WARNING
Electric shock hazard. Can cause injury or death. Before attempting to perform any service or maintenance, turn the electrical power to unit OFF at disconnect switch(es). Unit may have multiple power supplies.
Table of Contents
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Optional Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Blower Performance Data . . . . . . . . . . . . . . . . . . . . . . 4 I-Unit Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 II Placement and Installation . . . . . . . . . . . . . . . . . . . . 21 III- Start-Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 IV-Heating System Service Checks . . . . . . . . . . . . . . 43 V-Typical Operating Conditions . . . . . . . . . . . . . . . . . 47 VI-Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 VII-Sequence of Operation and Flow Charts . . . . . . 51

WARNING
Improper installation, adjustment, alteration, service
or maintenance can cause property damage, personal injury or loss of life. Installation and service must be performed by a licensed professional HVAC instale (or equivalent), service agency or the gas supplier.
CAUTION
As with any mechanical equipment, contact with sharp sheet metal edges can result in personal injury. Take care while handling this equipment and wear gloves and protective clothing.

Page 1

©2016 Lennox Industries, Inc.

SPECIFICATIONS

Gas Heating Performance

Model No. 1 AFUE
Input – Btuh

EL196UH030XE36B 96%
30,000

EL196UH045XE36B 96%
44,000

EL196UH070XE36B 96%
66,000

Output – Btuh

29,000

42,800

63,900

Temperature rise range – °F

25 – 55

35 – 65

35 – 65

Gas Manifold Pressure (in. w.g.) Nat. Gas / LPG/Propane

3.5 / 10

3.5 / 10

3.5 / 10

High static – in. w.g.

0.5

0.5

0.5

Energy Star® Certified

Yes

Yes

Yes

Connections Intake / Exhaust Pipe (PVC)

2 / 2

2 / 2

2 / 2

in.

Gas pipe size IPS

1/2

1/2

1/2

Condensate Drain Trap (PVC pipe) – i.d.

3/4

3/4

3/4

with furnished 90° street elbow

3/4 slip x 3/4 Mipt

3/4 slip x 3/4 Mipt

3/4 slip x 3/4 Mipt

with field supplied (PVC coupling) – o.d.

3/4 slip x 3/4 MPT

3/4 slip x 3/4 MPT

3/4 slip x 3/4 MPT

Indoor Blower

Wheel nom. dia. x width – in. Motor Type

10 x 8 DC Brushless

10 x 8 DC Brushless

10 x 8 DC Brushless

Motor output – hp

1/2

1/2

1/2

Tons of add-on cooling

1.5 – 3

1.5 – 3

1.5 – 3

Air Volume Range – cfm

175 – 1435

520 – 1345

550 – 1380

Electrical Data

Voltage

120 volts – 60 hertz – 1 phase

Blower motor full load amps

6.8

6.8

6.8

Maximum overcurrent protection

15

15

15

Shipping Data

lbs. – 1 package

120

129

134

NOTE – Filters and provisions for mounting are not furnished and must be field provided. 1 Annual Fuel Utilization Efficiency based on DOE test procedures and according to FTC labeling regulations. Isolated combustion system rating for non-weatherized furnaces.

SPECIFICATIONS

Gas Heating Performance

Model No. 1 AFUE
Input – Btuh

EL196UH090XE48C 96%
88,000

EL196UH110XE60C 96%
110,000

Output – Btuh

85,600

107,200

Temperature rise range – °F

50 – 80

45 – 75

Gas Manifold Pressure (in. w.g.) Nat. Gas / LPG/Propane

3.5 / 10

3.5 / 10

High static – in. w.g.

0.5

0.5

Energy Star® Certified

Yes

Yes

Connections Intake / Exhaust Pipe (PVC)

2 / 2

2 / 2

in.

Gas pipe size IPS

1/2

1/2

Condensate Drain Trap (PVC pipe) – i.d.

3/4

3/4

with furnished 90° street elbow

3/4 slip x 3/4 Mipt

3/4 slip x 3/4 Mipt

with field supplied (PVC coupling) – o.d.

3/4 slip x 3/4 MPT

3/4 slip x 3/4 MPT

Indoor Blower

Wheel nom. dia. x width – in. Motor Type

10 x 10 DC Brushless

11-1/2 x 10 DC Brushless

Motor output – hp

3/4

1

Tons of add-on cooling

2.5 – 4

3 – 5

Air Volume Range – cfm

760 – 1740

1055 – 2220

Electrical Data

Voltage

120 volts – 60 hertz – 1 phase

Blower motor full load amps

8.4

10.9

Maximum overcurrent protection

15

15

Shipping Data

lbs. – 1 package

158

170

NOTE – Filters and provisions for mounting are not furnished and must be field provided. 1 Annual Fuel Utilization Efficiency based on DOE test procedures and according to FTC labeling regulations. Isolated combustion system rating for non-weatherized furnaces.

Page 2

O PT IONAL AC C ES S ORIES – ORDER S EPARATELY

“B” Width Models

“C” Width Models

CABINET ACCESSORIES

Horizontal Suspension Kit – Horizontal only Return Air Base – Upflow only High Performance Economizer (Commercial Only)

51W10 50W98 10U53

51W10 50W99 10U53

CONDENSATE DRAIN KITS

Condensate Drain Heat Cable Crawl Space Vent Drain Kit

6 ft. 24 ft.
US Canada

26K68 26K69 51W18 15Z70

26K68 26K69 51W18 15Z70

CONTROLS

Blower Relay Kit (for two-stage outdoor units) Furnace Twinning Panel Furnace Twinning Kit E30 Smart Wi-Fi Thermostat Remote Outdoor Temperature Sensor

85W66 Y3653 16W72 20A65 X2658

85W66 Y3653 16W72 20A65 X2658

FILTER KITS

1 Air Filter and Rack Kit

Horizontal (end) Side Return

Size of filter – in. Single
Ten Pack Size of filter – in.

87L96 18 x 25 x 1
44J22 66K63 16 x 25 x 1

87L97 20 x 25 x 1
44J22 66K63 16 x 25 x 1

TERMINATION KITS

See Installation Instructions for specific venting information.

Direct Vent

Concentric

US – 2 in.

3 in.

Canada – 2 in.

3 in.

Flush-Mount

US – 2, 2-1/2 or 3 in.

Canada – 2, 2-1/2 or 3 in.

Wall – Close Couple

US – 2 in.

3 in.

Wall – Close Couple WTK

Canada – 2 in.

3 in.

Roof Termination Flashing Kit

2 in.

(no vent pipe – 2 flashings)

3 in.

71M80 – – –
44W92 – – –
51W11 51W12 22G44 44J40 30G28 81J20 15F75 44J41

69M29 60L46 44W92 44W93 51W11 51W12
– – 44J40
– – 81J20 15F75 44J41

VENTING

Flue Coupling

2 in.

17H92

17H92

1 Cleanable polyurethane frame type filter.

NOTE – Termination Kits (44W92, 44W93, 30G28, 51W12, 81J20) and Crawl Space Vent Drain Kit (15Z70) are certified to ULC S636 standard for use in Canada only.

Page 3

BLOWER DATA

EL196UH030XE36B PERFORMANCE (Less Filter)

External Static
Pressure in. w.g.

High (Black)

cfm

Watts

Air Volume / Watts at Various Blower Speeds

Medium-High (Brown)

Medium (Blue)

Medium-Low (Yellow)

cfm

Watts

cfm

Watts

cfm

Watts

0.00

1435

346

1170

191

1000

127

775

62

0.10

1400

351

1130

199

955

132

735

71

0.20

1360

358

1085

207

905

137

680

81

0.30

1325

370

1055

217

865

148

625

84

0.40

1300

382

1020

227

815

157

570

91

0.50

1265

387

990

231

785

161

515

95

0.60

1235

402

945

244

735

168

475

104

0.70

1200

411

910

253

710

175

425

107

0.80

1160

420

885

260

660

183

355

114

EL196UH045XE36B PERFORMANCE (Less Filter)

External Static
Pressure in. w.g.

High (Black)

cfm

Watts

Air Volume / Watts at Various Blower Speeds

Medium-High (Brown)

Medium (Blue)

Medium-Low (Yellow)

cfm

Watts

cfm

Watts

cfm

Watts

0.00

1460

335

1285

235

1190

170

910

85

0.10

1430

350

1260

245

1155

185

885

95

0.20

1405

365

1235

255

1125

200

860

105

0.30

1375

370

1205

265

1090

210

825

115

0.40

1350

380

1175

275

1055

215

780

125

0.50

1315

385

1145

285

1020

230

735

130

0.60

1245

375

1110

295

980

240

685

140

0.70

N/A

N/A

1070

305

940

250

640

145

0.80

N/A

N/A

1020

310

905

260

600

155

EL196UH070XE36B PERFORMANCE (Less Filter)

External Static
Pressure in. w.g.

High (Black)

cfm

Watts

Air Volume / Watts at Various Blower Speeds

Medium-High (Brown)

Medium (Blue)

Medium-Low (Yellow)

cfm

Watts

cfm

Watts

cfm

Watts

0.00

1445

315

1315

215

1215

165

930

85

0.10

1445

335

1275

230

1170

180

905

94

0.20

1415

345

1240

240

1125

190

870

101

0.30

1380

355

1205

250

1090

200

830

109

0.40

1345

370

1175

265

1055

210

790

117

0.50

1315

385

1150

280

1020

220

735

129

0.60

1275

390

1110

290

985

230

685

137

0.70

1210

395

1075

300

950

240

640

146

0.80

N/A

N/A

1030

305

915

250

595

148

Low (Red)

cfm

Watts

705

45

635

48

515

50

445

55

380

61

310

66

265

68

215

72

175

75

Low (Red)

cfm

Watts

870

75

830

85

800

90

755

95

710

105

665

115

620

125

575

135

530

140

Low (Red)

cfm

Watts

925

75

860

80

800

85

760

95

710

105

665

115

625

125

565

130

535

135

Page 4

BLOWER DATA

EL196UH090XE48C PERFORMANCE (Less Filter)

External Static
Pressure in. w.g.

High (Black)

cfm

Watts

Air Volume / Watts at Various Blower Speeds

Medium-High (Brown)

Medium (Blue)

Medium-Low (Yellow)

cfm

Watts

cfm

Watts

cfm

Watts

0.00

1765

375

1535

250

1410

180

1315

155

0.10

1735

390

1500

260

1365

200

1270

165

0.20

1700

405

1465

275

1330

215

1230

175

0.30

1660

425

1435

290

1295

225

1195

190

0.40

1640

435

1400

300

1265

235

1165

200

0.50

1615

450

1370

315

1230

250

1125

215

0.60

1575

465

1340

325

1190

265

1080

230

0.70

1530

470

1305

340

1150

280

1045

235

0.80

N/A

N/A

1260

345

1115

285

1000

245

Low (Red)

cfm

Watts

1155

115

1130

125

1095

135

1055

145

1010

155

965

165

925

180

885

190

845

195

EL196UH110XE60C PERFORMANCE (Less Filter)

Air Volume / Watts at Different Blower Speeds

Bottom Return Air, Side Return Air with Return Air from External Both Sides or Return Air from Bottom and One Side.
Static

Pressure in. w.g.

High (Black)

MediumHigh (Brown)

Medium (Blue)

MediumLow
(Yellow)

Low (Red)

Single Side Return Air – Air volumes in bold (over 1800 cfm) require Optional Return Air Base and field fabricated transition to accommodate 20 x 25 x 1 in. air filter in order to maintain proper air velocity.

High (Black)

MediumHigh (Brown)

Medium (Blue)

MediumLow
(Yellow)

Low (Red)

cfm Watts cfm Watts cfm Watts cfm Watts cfm Watts cfm Watts cfm Watts cfm Watts cfm Watts cfm Watts

0.00 2220 655 1975 440 1800 325 1665 390 1050 180 2180 685 1910 460 1750 345 1660 285 1430 195

0.10 2185 680 1925 460 1750 345 1625 285 1440 200 2155 705 1885 480 1720 360 1610 295 1415 205

0.20 2150 705 1880 480 1710 365 1590 300 1390 220 2130 725 1855 495 1685 380 1565 305 1380 220

0.30 2110 720 1850 495 1680 380 1560 320 1350 230 2085 745 1825 510 1655 390 1535 325 1335 230

0.40 2080 735 1810 520 1650 405 1515 330 1310 245 2060 760 1795 530 1625 405 1495 340 1295 245

0.50 2045 755 1785 530 1610 415 1470 350 1265 255 2030 775 1765 545 1585 425 1450 355 1255 265

0.60 2010 775 1740 545 1575 430 1440 370 1220 270 1995 785 1725 565 1550 435 1420 370 1205 275

0.70 1980 790 1705 565 1525 450 1400 375 1170 280 1960 795 1690 575 1505 455 1385 385 1165 290

0.80 1950 795 1670 580 1485 460 1360 390 1140 293 1895 790 1650 590 1465 470 1335 395 1120 295

Page 5

GAS VALVE
COMBUSTION AIR INDUCER

PARTS IDENTIFICATION

FLEXIBLE NO-HUB EXHAUST COLLAR BURNER BOX ASSEMBLY
DuralokPlusTM HEAT EXCHANGER
ASSEMBLY

TOP CAP

PRIMARY LIMIT

BAG ASSEMBLIES (shipping location)

OUTER ACCESS PANEL

COLD END HEADER BOX
COMBUSTION AIR PRESSURE
SWITCH

BLOWER ACCESS PANEL

BLOWER ASSEMBLY
CONTROL BOX former, circuit breaker and interlock
switch)
FIGURE 1

Page 6

I-UNIT COMPONENTS
ELECTROSTATIC DISCHARGE (ESD) Precautions and Procedures
CAUTION
Electrostatic discharge can affect electronic components. Take precautions to neutralize electrostatic charge by touching your hand and tools to metal prior to handling the control. EL196UHE unit components are shown in FIGURE 1. The combustion air inducer, gas valve and burners can be accessed by removing the outer access panel. The blower and control box can be accessed by removing the blower access panel. A-Control Box Components (FIGURE 2) Unit transformer (T1) and integrated ignition control (A92) are located in the control box. In addition, a door interlock switch (S51) is located in the control box.
Control Box
Transformer
Circuit Breaker
Door Interlock Switch
Integrated Control FIGURE 2 1. Transformer (T1) A transformer located in the control box provides power to the low voltage section of the unit. The transformers on all models are rated at 40VA with a 120V primary and 24V secondary. 2. Door Interlock Switch (S51) A door interlock switch rated 14A at 120VAC is located on the control box. The switch is wired in series with line voltage. When the blower door is removed the unit will shut down.

3. Circuit Breaker (CB8)

A 24V circuit breaker is also located in the control box. The switch provides overcurrent protection to the transformer (T1). The breaker is rated at 3A at 32V. If the current exceeds this limit the breaker will trip and all unit operation will shutdown. The breaker can be manually reset by pressing the button on the face.
4. Integrated Ignition Control (A92)

103217-03 & 107163-01

The hot surface ignition control system consisting of an integrated control (FIGURE 3 or FIGURE 5) with control terminal designations in TABLE 1, TABLE 2 and TABLE 3), sensor and ignitor (FIGURE 6). The integrated control and ignitor work in combination to ensure furnace ignition and ignitor durability. The integrated control, controls all major furnace operations. The integrated control also features a RED LED for troubleshooting and two accessory terminals rated at (1) one amp. See TABLE 4 for troubleshooting diagnostic codes. The nitride ignitor is made from a non-porous, high strength proprietary ceramic material that provides long life and trouble free maintenance.

TABLE 1

4-Pin Terminal Designation

PIN #

FUNCTION

1

Combustion Air Inducer Line

2

Ignitor Line

3

Combustion Air Inducer Neutral

4

Ignitor Neutral

TABLE 2

12-Pin Terminal Designations

PIN #

FUNCTION

1

High Limit Output

2

IFC 103217-03 Not Used IFC 107163-01 Flame Sense

3

24V Line

4

Not Used

5

Rollout Switch Out

6

24V Neutral

7

High Limit Input

8

Ground

9

Gas Valve Common

10

Pressure Switch In

11

Rollout Switch In

12

Gas Valve Out

Page 7

TABLE 3

1/4″ Quick Connect Terminals

120HUM

Humidifier 120VAC

LINE

120VAC

XFMR

Transformer 120VAC

CIRC

Indoor blower 120VAC

EAC

Indoor air quality accessory 120VAC

NEUTRALS

Common 120VAC

HUM24

Humidifier 24VAC

3/16″ Quick Connect Terminals

COOL

Cooling tap 24VAC

HEAT

Heating tap 24VAC

FAN

Continuous blower 24 VAC

PARK (no power)

Park terminal for speed taps

FS

Flame sense

24 COM

Common 24VAC

RED LED Flash Code 2
Off Heartbeat1 Continuous Rapid Flash
1 2 3 4
5
6
7
8 9 10 11 12 13
Note – 1
Note – 2
Note – 3

TABLE 4
Ignition Control 103217-03
Diagnostic Codes / Status of Furnace
No power to control or board fault detected Normal Operation – Idle, Continuous Fan, Cool Call For Heat / Burner Operation Reverse Line Voltage Polarity Improper Earth Ground Burner failed to light, or lost flame during heat demand Low Flame Signal – check flame sensor Watchguard – burner failed to light, exceeded maximum number of retries or recycles. Not Used Primary or Secondary Limit Open or Watchguard Mode – Limit Switch Open longer than 3 minutes Rollout Switch Open Pressure Switch failed to close or opened during heat demand Watchguard – Pressure Switch opened 5 times during one heat demand Pressure Switch stuck closed prior to activation of combustion air inducer Flame Sensed without gas valve energized Low Line Voltage
Notes A “Heartbeat” is indicated by a “Slow Flash” – 1 sec on 1 sec off, repeating Error codes are indicated by a “rapid flash” – the LED flashes X times at ½ second on ½ second off, remains off for 3 seconds then repeats. Last 10 error codes are stored in memory including when power is shut off to the unit. – To recall, pressand release button, most recent will be displayed first, LED off for 3 sec, then next error code is displayed, etc. To clear error codes, depress and hold button longer than 5 seconds.

Page 8

IGNITION CONTROL 103217-03

RED LED RECALL BUTTON

BLOWER OFF DELAY

FIGURE 3 Electronic Ignition (FIGURE 13)

On a call for heat the integrated control monitors the combustion air inducer pressure switch. The control board will not begin the heating cycle if the pressure switch is closed (by-passed). Once the pressure switch is determined to be open, the combustion air inducer is energized. When the differential in the pressure switch is great enough, the pressure switch closes and a 15-second pre-purge begins. If the pressure switch is not proven within 2-1/2 minutes, the integrated control goes into Watchguard-Pressure Switch mode for a 5-minute re-set period.
After the 15-second pre-purge period, the ignitor warms up for 20 seconds during which the gas valve opens at 19 seconds for a 4-second trial for ignition. The ignitor remains energized for the first 3 seconds during the 4 second trial. If ignition is not proved during the 4-second period, the integrated control will try four more times with an inter purge and warm-up time between trials of 35 seconds.

After a total of five trials for ignition (including the initial trial), the integrated control goes into Watchguard-Flame Failure mode. After a 60-minute reset period, the integrated control will begin the ignition sequence again.
Fan Time Control – Ignition Control 103217-03
Heating Fan On Time
The fan on time of 30 seconds is not adjustable. Heating Fan Off Time Fan off time (time that the blower operates after the heat demand has been satisfied) can be adjusted by moving the jumper to a different setting. The unit is shipped with a factory fan off setting of 90 seconds. For customized comfort, monitor the supply air temperature once the heat demand is satisfied. Note the supply air temperature at the instant the blower is de-energized.
Adjust the fan-off delay to achieve a supply air temperature between 90° – 110° at the instant the blower is de-energized. (Longer delay times allow for lower air temperature, shorter delay times allow for higher air temperature). See FIGURE 4.
Cooling Fan On Time
The fan on time is 2 seconds and is not adjustable.
Cooling Fan Off Time
The control has a 45 second fan off delay after cooling demand has been met. This delay is factory set and not adjustable.
HEAT FAN-OFF TIME IN SECONDS

NO JUMPER
To adjust fan-off timing, reposition jumper across pins to achieve desired setting.

60 Second off Time

90 Second off Time

120 Second off Time

180 Second off Time

60 90 120 180 60 90 120 180 60 90 120 180 60 90 120 180

FIGURE 4

Page 9

RED LED Flash Code Off On
Fast Heartbeat3 Slow Heartbeat1
1 Flash2 2 Flashes2 3 Flashes2 4 Flashes2 5 Flashes2 6 Flashes2
7 Flashes2
8 Flashes2 9 Flashes2 10 Flashes2 11 Flashes2 12 Flashes2 13 Flashes2
Note – 1
Note – 2
Note – 3
Note – 4

TABLE 5 Ignition Control 107163-01
Diagnostic Codes / Status of Furnace
No Power to Control or Board Fault Detected Board Fault Detected Call for Heat / Burner Operation Normal Operation ­ Idle, Continuous Fan, or Cool Reverse Line Voltage Polarity or Phasing of 120V power Improper earth ground Burner failed to light, or lost flame during heat demand Low flame signal ­ check flame sensor Watchguard ­ burner failed to light, exceeded maximum number of retries/recycles, 1 hour lockout Not used Primary or Secondary limit switch open or Watchguard mode ­ Limit Switch open longer than 3 minutes
Roll-out Switch Open Pressure Switch failed to close or opened during heat demand, inducer on Watchguard – Pressure switch opened 5 times during a single heating demand Pressure switch stuck closed prior to activation of Combustion Air Inducer Flame sensed without gas valve energized Low line voltage
Notes A slow heartbeat is indicated by 1s on / 1s off. It is used for idle, continuous fan and cool modes. Error codes are indicated by a “rapid flash” – the LED flashes X times at ½ second on ½ second off, remains off for 3 seconds then repeats. A fast heartbeat is indicated by 0.5s on / 0.5s off. It is only used during a heat call. Last 10 error codes are stored in memory including when power is shut off to the unit. – To recall, press, and release button, most recent will be displayed first, LED off for 3 sec, then next error code is displayed, etc. To clear error codes, depress and hold button longer than 5 seconds.

IGNITION CONTROL 107163-01
PARKS

HUM24 24VCOM COOL HEAT FAN

Ignition Control 107163-01

The heat fan-on time of 30 seconds is not adjustable. The cool fan-on time of 2 seconds is not adjustable. The heat fan-off delay (amount of time that the blower operates after the heat demand has been satisfied) may be adjusted by changing the two position dip switch on the integerated control, to one of four selections. Blower off delay is factory set at 90 seconds. For other blower off delay settings, please refer to the following chart:

Blower Delay Select

SW2-1

SW2-2

60

OFF

ON

90

OFF

OFF

120

ON

OFF

180

ON

ON

Factory Setting is 90

Push Button Error Recall

Diagnostic LED
FIGURE 5

Heating Blower Off Delay Selector Switch

Page 10

Burner Box Assembly

Burner Assembly

Rollout Switch(s)

Flame Sensor

Ignitor

Burner Box Front

Gas Valve FIGURE 6

B-Heating Components
Combustion air inducer (B6), primary limit control (S10), ignitor, burners, flame rollout switch (S47), gas valve (GV1), combustion air pressure switch (S18), and heat exchangers are located in the heating compartment. The heating compartment can be accessed by removing the outer access panel.
1. Flame Rollout Switches (FIGURE 6)
Flame rollout switches S47 are SPST N.C. high temperature limits located on the left and right of the front buner box plate. S47 is wired to the burner ignition control A92. When either of the switches sense flame rollout (indicating a blockage in the combustion passages), the flame rollout switch trips, and the ignition control immediately closes the gas valve. Switch S47 in all ML196UHE units is factory preset to open at 210F + 12F (99C + 6.7C) on a temperature rise. All flame rollout switches are manual reset. See table 4 flash code 8 for troubleshooting
2. Heat Exchanger (FIGURE 7)
EL196UHE units use an aluminized steel primary and stainless steel secondary heat exchanger assembly. Heat is transferred to the air stream from all surfaces of the heat exchanger. The shape of the heat exchanger ensures maximum efficiency.

The combustion air inducer pulls fresh air through the burner box. This air is mixed with gas in the burners. The gas / air mixture is then burned at the entrance of each clamshell. Combustion gases are then pulled through the primary and secondary heat exchangers and exhausted out the exhaust vent pipe.
3. Primary Limit Control (FIGURE 7)
Primary limit (S10) used on EL196UHE units is located in the heating vestibule panel. When excess heat is sensed in the heat exchanger, the limit will open. Once the limit opens, the furnace control energizes the supply air blower and de-energizes the gas valve. The limit automatically resets when unit temperature returns to normal. The switch is factory set and cannot be adjusted. For limit replacement remove wires from limit terminals, remove mounting screws, rotate limit switch 90 degrees and slowly remove from the vestibule panel. Install replacement limit with same care. See TABLE 4 or TABLE 5 flash code 7 for troubleshooting if limit switch opens during operation.

Page 11

Primary Limit Location and Heat Exchanger

Install limit face down

FIGURE 7 4. Gas Valve (FIGURE 8)

The EL196UHE uses an internally redundant valve to assure safety shut-off. If the gas valve must be replaced, the same type valve must be used.
24VAC terminals and gas control switch are located on top of the valve. All terminals on the gas valve are connected to wires from the ignition control. 24V applied to the terminals opens the valve.
Inlet and outlet pressure taps are located on the valve. A manifold adjustment screw is also located on the valve. An LP/Propane changeover kit is available.

MANIFOLD PRESSURE ADJUSTMENT SCREW (under barbed fitting)

MANIFOLD PRESSURE
OUTLET PORT

INLET PRESSURE
PORT GAS VALVE SHOWN IN ON POSITION
FIGURE 8

5. Flame Sensor (FIGURE 6)
A flame sensor is located on the left side of the burner support. The sensor is mounted on the front burner box plate and the tip protrudes into the flame envelope of the leftmost burner. The sensor can be removed for service (use steel wool only to clean) without removing any part of the burners. During operation, flame is sensed by current passed through the flame and sensing electrode. The ignition control allows the gas valve to remain open as long as flame signal is sensed.
NOTE – The EL196UHE is polarity sensitive. Make sure that the furnace is wired correctly and is properly grounded.
A microamp DC meter is needed to check the flame signal on the integrated control.
Flame (microamp) signal is an electrical current which passes from the integrated control to the sensor during unit operation.
Current passes from the sensor through the flame to ground to complete a safety circuit.
To Measure Flame Signal – Integrated Control:
Use a digital readout meter capable of reading DC microamps.
See FIGURE 9 for flame signal check. 1 – Set the meter to the DC amps scale.
2 – Turn off supply voltage to control.
3 – Remove sensor wire from integrated control.
4 – Connect (-) lead to flame sensor wire.
5 – Connect (+) lead to Terminal FS on integrated control.
6 – Turn supply voltage on and close thermostat contacts to cycle system.
7 – When main burners are in operation for two minutes, take reading.
6. Ignitor (Figure 6)
EL196UHE units use a nitride ignitor made from a proprietary ceramic material. To check ignitor, measure its resistance and voltage. A value of 39 to 70 ohms indicates a good ignitor. Voltage to the ignitor should be 102 – 132VAC. See FIGURE 10 for resistance and voltage checks.

Page 12

Flame Signal In Microamps

Normal 1.5

Low 0.5 – 1.4

Drop Out 0.4

Measuring Flame Signal

Flame Sensor Wire

Remove sensor from integrated control and connect alligator clip
(-) to flame sensor lead.

Intergrated Control

Flame Sensor Terminal

Multi-Meter Set Dial to DC MicroAmps (+)

(+)
(+) To Control Sensor Terminal
Remove sensor from integrated control and connect alligator clip
(+) to terminal on control.
FIGURE 9

(-) To Flame Terminal

Page 13

Test 1 Check ignitor circuit for correct resistance.
Remove 4-pin plug from control. Check ohms reading across terminals 2 and 4. Reading should be between 39 and 70 ohms. If
value is correct, this is the only test needed. If the reading on the meter is not correct, (0 or
infinity) then a second test is needed.
Multi-Meter (set to ohms)
Test 2 Check ignitor for correct resistance. Seperate the 2-pin jack-plug near the manifold and check resistance of ignitor at the plug. Reading should be between 39 and 70 ohms. If the reading is correct, then the problem is with the wiring between the jack-plug and the control. If reading is not correct, the issue is the ignitor.
Multi-Meter (set to ohms)
Test 3 Check ignitor for correct voltage Insert meter probes into terminals 2 and 4 (use small diameter probes in order not to damage plug). Check voltage during 20 second ignitor warm up period. Voltage should read 120 volts + 10%. If voltage reads below these values, check for correct supply voltage to furnace.
Multi-Meter (set to VAC)
FIGURE 10
Page 14

7. Combustion Air Inducer & Cold End Header Box

All EL196UHE units use a combustion air inducer (B6) to move air through the burners and heat exchanger during heating operation. The blower uses a shaded pole 120VAC motor. The motor operates during all heating operation and is controlled by integrated control A92. Blower operates continuously while there is a call for heat. The integrated control will not proceed with the ignition sequence until combustion air inducer operation is sensed by the proving switches.
The combustion air inducer is installed on the cold end header box. The cold end header box is a single piece made of hard plastic. The box has an internal channel where the combustion air inducer creates negative pressure at unit start up. The channel contains an orifice used to regulate flow created by the combustion air inducer.
The box has pressure taps for the combustion air inducer pressure switch hoses. The pressure switch measures the pressure across the combustion air inducer orifice or difference in the channel and the box. If replacement is necessary the gaskets used to seal the box to the
vestibule panel and the combustion air inducer to the
box, must also be replaced.

TABLE 6

Unit

Combustion Air Inducer Orifice Size

-030

0.525″

-045

0.618

-070

0.775″

-090

0.905″

-110

1.040″

8. Combustion Air Pressure Switch (FIGURE 11)

EL196UHE series units are equipped with a differential pressure switch located on the cold end header box. The switch monitors across the combustion air inducer orifice to insure proper flow through the heat exchanger.
The switch is a SPST N.O. pressure switch electrically connected to the integrated control. The purpose of the switch is to prevent burner operation if the combustion air inducer is not moving enough air for proper combustion.
On start-up, the switch monitors whether the combustion air inducer is operating. It closes a circuit to the integrated control when the difference in pressure across the combustion air inducer orifice exceeds a non-adjustable factory setting. If the switch does not successfully sense the required differential, the switch cannot close and the furnace cannot operate.

Pressure Switch
BRACKET

24VAC TERMINALS

TAP TAP

FIGURE 11

If the flue or air inlet become obstructed during operation, the switch senses a loss of pressure differential and opens the circuit to the integrated control. If the condensate line is blocked, water will back up into the header box and reduce the pressure differential across the switch. The pressure switch opens if the differential drops below the set point. See TABLE 7.
Checks of pressure differential can aid in troubleshooting. When measuring the pressure differential, readings should be taken at the pressure switch. See FIGURE 12 and TABLE 8. Lack of differential usually indicates problems in the intake or exhaust piping, but may indicate problems in the heat exchanger, condensing coil, header boxes, combustion inducer or other components.

TABLE 7

Altitude ft.

Unit -030

0-4500
Set Point “w.c.
-0.65

4501-7500
Set Point “w.c.
-0.65

7501-10000 Set Point “w.c.
-0.60

-045 -070

-0.65 -0.95

-0.65 -0.85

-0.60 -0.75

-090

-0.90

-0.80

-110

-0.90

-0.85

*Set point is factory set and non-adjustable

-0.65 -0.65

Page 15

Measuring Pressure Differential

Red and Black Tubing or Red Tubing (negative -)
To Cold End Header Box

Field Provided Tubing To Pressure Switch

Black Tubing (positive +)
To Cold End Header Box

“+” High

1 – Remove thermostat demand and allow unit to cycle off.
2 – Install a tee in the negative (-) line (red and black tubing or red tubing) and a tee in the positive (+) line (black tubing) running from the pressure switch to the cold end header box.
3 – Install a manometer with hose from the negative (-) side of the manometer to the tee installed in the negative (-) line and with hose from the positive (+) side of the manometer to the tee in the positive (+) line.
NOTE – Both sides of the cold end header box are
negative. How
sure than the (-) port.

“-” Low
4 – Operate unit and observe manometer reading. Readings will change as heat exchanger warms. a. Take one reading immediately after start-up. b. Take a second reading after unit has reached steady state (approximately 5 minutes). This will be the pressure differential. The pressure differential should be greater than those listed in table 7.
5 – Remove thermostat demand and allow to cycle off.
6 – Remove manometer and tee’s. Reinstall combustion air sensing hoses to the pressure switch.

FIGURE 12

1

ON OFF

Pre -Purge

DEMAND CAI IGNITOR GAS VALVE INDOOR BLOWER

ELECTRONIC IGNITION

15

34

38

80

Ignitor Warm-up

Trial for Ignition

Blower “On”* Delay

5 SEC
Post Purge

*Blower on time will be 30 seconds after flame is sensed. Blower off time will depend on “OFF TIME” Setting.

FIGURE 13

Page 16

TABLE 8

Problem

Corrective Action

Pressure switch stuck closed

Check that the pressure switch is open without the combustion air inducer operating. Replace if defective.

Pressure switch does not close due to obstruction in vent Check for restricted vent. Remove all blockage. Check for

pipe.

proper vent sizing. See table 13.

Pressure switch does not close due to incorrect routing of Check that the pressure switch tubing is correctly routed.

the pressure switch tubing.

Correctly route pressure witch line.

Pressure switch does not close due to obstructions in the Remove any obstructions from the the pressure switch

pressure switch line.

line and/or taps

Pressure switch tubing damaged.

Check pressure switch tubing for leaks. Replace damaged tubing if necessary.

Condensate in pressure switch tubing.

Check pressure switch tubing for condensate. Remove condensate from tubing.

Pressure switch does not close due to a low differential pressure across the pressure switch.

Check the differential pressure across the pressure switch. Check for restricted inlet vent. Remove all blockage. Check for proper vent sizing and run length.

Wrong pressure switch installed in the unit, or pressure switch is out of calibration

Check that the correct pressure switch is installed in the unit. Replace pressure switch if necessary.

Miswiring of furnace or improper connections at pressure Check for correct wiring and loose connections. Correct

switch.

wiring and/or replace any loose connections.

Pressure switch failure.

If all the above modes of failure have been checked, the pressure switch may have failed. Replace pressure switch and determine if unit will operate.

Damaged condensate trap.

Check trap for any cracks or damage and replace if necessary.

Cold end header box does not drain properly.

Check that the furnace is set properly with a slight tilt (0 – 1/2″) towards the front if necessary. See furnace installation instruction.

Air leakage around the combustion air inducer gasket.

Check gasket and replace if necessary.

Air leakage around the cold end header box gasket.

Check gasket and replace if necessary.

Damaged cold end header box tubing.

Check tubing and replace if necessary.

Page 17

C- Blower Compartment
IMPORTANT
Each blower is statically and dynamically balanced as an assembly before installation in the unit.
EL196UHE units are equipped with a constant torque ECM motor. It has a DC motor coupled to an electronic control module both contained in the same motor housing. The motor is programmed to provide constant torque at each of the five selectable speed taps. Each tap requires 24 volts to energize.
Input Voltage Requirements
The circuit is designed to be operated with AC voltage. To enable a tap requires 12 to 33VAC. Expected current draw will be less than 20mA.
Troubleshooting the Motor
Troubleshooting the motor is an easy process. Follow steps below.
1 – Shut off power to unit. 2 – Remove input plugs P48 and P49 from motor. See
FIGURE 17 for troubleshooting procedure.
Note – FIGURE 17 is a typical ignition control illustration. If correct voltage is present in tests 1 and 2 and motor is not operating properly, replace motor. The motor is not field repairable. If replacing the indoor blower motor or blower wheel is necessary, placement is critical. The blower wheel must be centered in the blower housing as shown in FIGURE 14. When replacing the indoor blower motor the set screw must be aligned and tightened with the motor shaft as shown in FIGURE 15.
1. Secondary Limit Controls
The secondary limit is located in the blower compartment on the back side of the blower housing. See FIGURE 16. When excess heat is sensed in the blower compartment, the limit will open. If the limit is open, the furnace control energizes the supply air blower and closes the gas valve. The limit automatically resets when unit temperature returns to normal. The secondary limit cannot be adjusted.

BLOWER WHEEL REPLACEMENT
Center Blower Wheel in Blower Housing
FIGURE 14 ALIGN AND TIGHTEN SET SCREW WITH
FLAT SIDE OF MOTOR SHAFT Housing Hub Set Screw Motor
Shaft
FIGURE 15
SECONDARY LIMIT CONTROL
Secondary Limits

FIGURE 16

Page 18

P49

5
4 3 2 1

Multi-Meter (set to VAC)
12 0

Test 1

N G
L C

P48

Turn on power to unit. Check for 120 volts across terminals “L” and “N” on input plug P48. If voltage is present continue

stream of plug P48 and proceed to test 3.

Multi-Meter (set to VAC)
120
Test 3 (if necesssary)
Check for 120 volts across terminals “CIRC” and “Neutrals” on the integrated control. If voltage is present, problem is with the harness. If voltage is not present problem may be may be with the integrated control.

P49

5
4
3 2 1

Multi-Meter (set to VAC)
24

Multi-Meter (set to VAC)
24

N G L C
P48 Test 2
Switch thermostat to CONTINUOUS FAN MODE. Check for 24 volts across terminal “C” on inpult plug P48and speed tap used for continuous fan. (1, 2, 3, 4 or 5) on input plug P49. If 24 volts is not present problem may be up stream of plug P49. Proceed to test 4.

Test 4 (if necessary)
lem is with the harness. If voltage is not present problem may be may be with the integrated control

FIGURE 17

Page 19

Replacing the Motor Module
1 – Disconnect electrical power to unit. 2 – Remove unit access panel. 3 – Unplug the two harnesses from the motor control
module. See FIGURE 18. 4 – Remove the two hex head bolts securing the motor
control module to the motor (see FIGURE 19). 5 – Slide the motor control module away from the motor
to access and disconnect the internal three wire connector. It is not necessary to remove blower motor itself. Set both hex head bolts aside.
Unplug the Two Harness Connection

TWO HARNESS CONNECTIONS

MOTOR MOTOR CONTROL MODULE

FIGURE 18
Remove the Hex Head Bolts
REMOVE BOTH HEX HEAD BOLTS
FIGURE 19 Testing the Motor (FIGURE 20) If any motor fails the below tests, do not install the new control module. The motor is defective and it also must be replaced. The new control can fail if placed on a defective motor.
1 – Using an ohmmeter check the resistance from any one of the motor connector pins to the aluminum end plate of the motor. This resistance should be greater than 100k ohms.
2 – Check the resistances between each of the three motor connector pins. These should all read approximately the same resistance within an ohm.
3 – Check to see if the blower wheel spins freely.

Motor Test

FIGURE 20

TABLE 9

Scale Measurement range in

words

2 M

two megohm-two million ohms

200 K

two hundred kilo-ohm-two hundred thousand ohms

20 K

twenty kilo-ohm-twenty thousand ohms

2 K

two kilo-ohm two-thousand ohms

200

two hundred ohms

Motor Module Installation

ohms
0 – 2,000,000 0 – 200,000
0 – 20,000
0 – 2,000 0 – 200

All replacement motor control modules look similar; however, each module is designed for a specific motor size. It is very important to make sure that you are using the correct replacement motor control module. USE OF THE WRONG MOTOR CONTROL MODULE MAY RESULT IN
UNEXPECTED UNIT OPERATION.
1 – Verify electrical power to unit is disconnected.
2 – Connect three-wire harness from motor to control module.
3 – Mount new motor control module to motor using two hex head bolts removed in FIGURE 19. Torque bolts to 22 inch pounds or 1/16th clock wise turn.
4 – Reconnect the two harnesses to the motor control module.
5 – The electrical connectors of the motor should be facing down to form a drip loop (FIGURE 21) This will directs moisture away from the motor and its electric connections on the motor.

Drip Loop

BACK OF CONTROL MODULE

CONNECTOR ORIENTATION BETWEEN 4 AND 8
O’CLOCK

DRIP LOOP
FIGURE 21

Page 20

II-PLACEMENT AND INSTALLATION

Pipe & Fittings Specifications

All pipe, fittings, primer and solvent cement must conform with American National Standard Institute and the American Society for Testing and Materials (ANSI/ASTM) standards. The solvent shall be free flowing and contain no lumps, undissolved particles or any foreign matter that adversely affects the joint strength or chemical resistance of the cement. The cement shall show no gelation, stratification, or separation that cannot be removed by stirring. Refer to TABLE 10 for approved piping and fitting materials.

TABLE 10

PIPING AND FITTINGS SPECIFICATIONS

Schedule 40 PVC (Pipe)

D1785

Schedule 40 PVC (Cellular Core Pipe)*

F891

Schedule 40 PVC (Fittings)

D2466

Schedule 40 CPVC (Pipe)

F441

Schedule 40 CPVC (Fittings)

F438

SDR-21 PVC or SDR-26 PVC (Pipe)

D2241

SDR-21 CPVC or SDR-26 CPVC (Pipe)

F442

Schedule 40 ABS Cellular Core DWV (Pipe)*

F628

Schedule 40 ABS (Pipe)

D1527

Schedule 40 ABS (Fittings)

D2468

ABS-DWV (Drain Waste & Vent) (Pipe & Fittings)

D2661

PVC-DWV (Drain Waste & Vent) Pipe & Fittings)

D2665

PRIMER & SOLVENT CEMENT

ASTM SPECIFICATION

PVC & CPVC Primer

F656

PVC Solvent Cement

D2564

CPVC Solvent Cement

F493

ABS Solvent Cement

D2235

PVC/CPVC/ABS All Purpose Cement For Fittings & Pipe of the same material

D2564, D2235, F493

ABS to PVC or CPVC Transition Solvent Cement

D3188

CANADA PIPE & FITTING & SOLVENT CEMENT

MARKING

PVC & CPVC Pipe and Fittings

PVC & CPVC Solvent Cement

ABS to PVC or CPVC Transition Cement POLYPROPYLENE VENTING SYSTEM

ULCS636

PolyPro® by Duravent

InnoFlue® by Centrotherm

UL 1738 CERTIFIED GAS VENTING SYSTEM

IPEX System1738 Schedule 40 PVC Pipes and Fittings
IPEX System1738 PVC FGV Cement & Primer

  • Not approved as of 12-1-2022

UL1738

IMPORTANT
Exhaust and intake connections are made of PVC. Use PVC primer and solvent cement when using PVC vent pipe. When using ABS vent pipe, use transitional solvent cement to make connections to the PVC fittings in the unit.
CAUTION
Solvent cements for plastic pipe are flammable liquids and should be kept away from all sources of ignition. Do not use excessive amounts of solvent cement when making joints. Good ventilation should be maintained to reduce fire hazard and to minimize breathing of solvent vapors. Avoid contact of cement with skin and eyes.
Use PVC primer and solvent cement or ABS solvent cement meeting ASTM specifications, refer to TABLE 10. As an alternate, use all purpose cement, to bond ABS, PVC, or CPVC pipe when using fittings and pipe made of the same materials. Use transition solvent cement when bonding ABS to either
PVC or CPVC.
Low temperature solvent cement is recommended during cooler weather. Metal or plastic strapping may be used for vent pipe hangers. Uniformly apply a liberal coat of PVC primer for PVC or use a clean dry cloth for ABS to clean inside socket surface of fitting and male end of pipe to depth of fitting socket. Canadian Applications Only – Pipe, fittings, primer and solvent cement used to vent (exhaust) this appliance must be certified to ULC S636 and supplied by a single manufacturer as part of an approved vent (exhaust) system. In addition, the first three feet of vent pipe from the furnace flue collar must be accessible for inspection.

Page 21

TABLE 11

OUTDOOR TERMINATION USAGE*

STANDARD

CONCENTRIC

Input Size

Vent Pipe Dia. in.

Flush Mount Kit
51W11 (US)
51W12 (CA)

Wall Kit

2 inch
22G44 (US) 430G28 (CA)

3 inch
44J40 (US) 481J20 (CA)

Field Fabricated

1-1.2 inch
71M80 (US)
444W92 (CA)

2 inch

3 inch

69M29 (US)
444W92 (CA)

60L46 (US) 444W93 (CA)

61-1.2

3YES

YES

1YES

5YES

2YES

030, 045

2 2-1/2

3YES 3YES

YES YES

1YES 1YES

5YES 5YES

2YES 2YES

3

3YES

YES

1YES

5YES

2YES

61-1/2

3YES

YES

1YES

5YES

2YES

2

3YES

YES

1YES

5YES

2YES

070

2-1/2

3YES

YES

1YES

5YES

2YES

3

3YES

YES

1YES

5YES

2YES

2

3YES

YES

5YES

YES

YES

090

2-1/2

3YES

YES

5YES

YES

YES

3

3YES

YES

5YES

YES

YES

2

YES

YES

5YES

YES

YES

110

2-1/2

YES

YES

5YES

YES

YES

3

YES

YES

5YES

YES

YES

NOTE – Standard Terminations do not include any vent pipe or elbows external to the structure. Any vent pipe or elbows external to the structure must be included in total vent length calculations. See vent length tables.

  • Kits must be properly installed according to kit instructions.
    1Requires field-provided outdoor 1-1/2″ exhaust accelerator.
    2Concentric kits 71M80 and 44W92 include 1-1/2″ outdoor accelerator, when uses with 030, 045 and 070 input models. When using 1-1/2 inch vent pipe, transistion to 2″ pipe before installing concentric kit.
    3 Flush mount kits 51W11 and 51W12 includes 1-1/2 in. outdoor exhaust accelerator, required when used with 030, 045, 070 and 090 input models. When using 1-1/2″ vent pipe, transition to 2″ pipe before installing flushmount kit.
    4 Termination kits 30G28, 44W92, 4493 and 81J20 are certified to ULC S636 for use in Canada only.
    5 See table 16 for vent accelerator requirements.
    6 Requires field provided 2″ to 1-1/2″ reducer.

Joint Cementing Procedure
All cementing of joints should be done according to the specifications outlined in ASTM D 2855.
DANGER
DANGER OF EXPLOSION! Fumes from PVC glue may ignite during system check. Allow fumes to dissipate for at least 5 minutes before placing unit into operation..
1 – Measure and cut vent pipe to desired length. 2 – Debur and chamfer end of pipe, removing any
ridges or rough edges. If end is not chamfered, edge of pipe may remove cement from fitting socket and result in a leaking joint. NOTE – Check the inside of vent pipe thoroughly for any obstruction that may alter furnace operation. 3 – Clean and dry surfaces to be joined

4 – Test fit joint and mark depth of fitting on outside of pipe.
5 – Uniformly apply a liberal coat of PVC primer for PVC or use a clean dry cloth for ABS to clean inside socket surface of fitting and male end of pipe to depth of fitting socket.
NOTE – Time is critical at this stage. Do not allow primer to dry before applying cement.
6 – Promptly apply solvent cement to end of pipe and inside socket surface of fitting. Cement should be applied lightly but uniformly to inside of socket. Take care to keep excess cement out of socket. Apply
second coat to end of pipe.
7 – Immediately after applying last coat of cement to pipe, and while both inside socket surface and end of pipe are wet with cement, forcefully insert end of pipe into socket until it bottoms out. Turn PVC pipe 1/4 turn during assembly (but not after pipe is fully
inserted) to distribute cement evenly. DO NOT turn
ABS or cellular core pipe

Page 22

NOTE – Assembly should be completed within 20 seconds after last application of cement. Hammer blows should not be used when inserting pipe. 8 – After assembly, wipe excess cement from pipe at end of fitting socket. A properly made joint will show a bead around its entire perimeter. Any gaps may indicate an improper assembly due to insufficient solvent. 9 – Handle joints carefully until completely set.
Venting Practices
Piping Suspension Guidelines
SCHEDULE 40 PVC – 5′
all other pipe* – 3′

  • See Piping and Fittings Specifications table
    NOTE – Isolate piping at the point where it exits the outside wall or roof in order to prevent transmission of vibration to the structure.

Wall Thickness Guidelines
24″ maximum 3/4″ minimum

inside

Wall outside

FIGURE 22
1 – In areas where piping penetrates joists or interior walls, hole must be large enough to allow clearance on all sides of pipe through center of hole using a hanger.
2 – When furnace is installed in a residence where unit is shut down for an extended period of time, such as a vacation home, make provisions for draining condensate collection trap and lines.

REPLACING FURNACE THAT WAS PART OF A COMMON VENT SYSTEM
CHIMNEY OR GAS
VENT (Check sizing
for water heater only)

FURNACE (Replaced)

WATER HEATER

OPENINGS (To Adjacent
Room)

If replacing a furnace which was commonly vented with another gas appliance, the size of the existing vent pipe for that gas appliance must be checked. Without the heat of the original furnace flue products, the existing vent pipe is probably oversized for the single water heater or other appliance. The vent should be checked for proper draw with the remaining appliance.
FIGURE 23
Exhaust Piping (FIGURE 26 and FIGURE 27 )
Route piping to outside of structure. Continue with installation following instructions given in piping termination section.
CAUTION
Do not discharge exhaust into an existing stack or stack that also serves another gas appliance. If vertical discharge through an existing unused stack is required, insert PVC pipe inside the stack until the end is even with the top or outlet end of the metal stack.
CAUTION
The exhaust vent pipe operates under positive pressure and must be completely sealed to prevent leakage of combustion products into the living space.

Page 23

Vent Piping Guidelines
NOTE – Lennox has approved the use of DuraVent® and Centrotherm manufactured vent pipe and terminations as an option to PVC. When using the PolyPro® by DuraVent or InnoFlue® by Centrotherm venting system the vent pipe requirements stated in the unit installation instruction ­ minimum & maximum vent lengths, termination clearances, etc. ­ apply and must be followed. Follow the instructions provided with PoyPro by DuraVent and InnoFlue by Centrotherm venting system for assembly or if requirements are more restrictive. The PolyPro by Duravent and InnoFlue by Centrotherm venting system must also follow the uninsulated and unconditioned space criteria listed in TABLE 15 .
The EL196UHE can be installed as either a Non-Direct Vent or a Direct Vent gas central furnace.
NOTE – In Non-Direct Vent installations, combustion air is taken from indoors and flue gases are discharged outdoors. In Direct Vent installations, combustion air is taken from outdoors and flue gases are discharged outdoors.
Intake and exhaust pipe sizing — Size pipe according to TABLE 12 (minimum pipe length allowed) and TABLE 13 (maximum pipe length allowed). Count all elbows inside and outside the home.
Regardless of the diameter of pipe used, the standard roof and wall terminations described in section Exhaust Piping Terminations should be used. Exhaust vent termination pipe is sized to optimize the velocity of the exhaust gas as it exits the termination. Refer to TABLE 16.
In some applications which permit the use of several different sizes of vent pipe, a combination vent pipe may be used. Contact Lennox’ Application Department for assistance in sizing vent pipe in these applications. NOTE – The exhaust collar on all models is sized to accommodate 2″ Schedule 40 vent pipe. In horizontal applications, any transition to exhaust pipe larger than 2″ must be made in vertical runs of the pipe. Therefore a 2″ elbow must be added before the pipe is transitioned to any size larger than 2″. This elbow must be added to the elbow count used to determine acceptable vent lengths. Contact the Application Department for more information concerning sizing of vent systems which include multiple pipe sizes.

Horizontal Installation Offset Requirements Exhaust Pipe

Horizontal Gas Furnace

12″ Max.

12″ Min.

NOTE ward unit. A minimum of 1/4″ (6mm) drop for each 12″ (305mm) of horizontal run is mandatory for drainage. NOTE – Exhaust pipe MUST be glued to furnace exhaust fitting, unless the optional glueless vent adapter kit 17H92 is used.. NOTE – Exhaust piping should be checked carefully to make sure there are no sags or low spots.
FIGURE 24

TABLE 12

MINIMUM VENT PIPE LENGTHS

EL196UHE Model

MIN. VENT LENGTH*

030, 045, -070, -090, 110

15 ft. or 5 ft. plus 2 elbows or 10 ft. plus 1 elbow

*Any approved termination may be added to the minimum length listed. Two 45 degree elbows are the equivalent of one 90 degree elbow.

Use the following steps to correctly size vent pipe diameter.

Piping Size Process

What is the
1 furnace capacity?

Which style termination

2

being used?

Standard or

concentric?.

Which needs

3

most elbows? Intake or

exhaust?

How many elbows?
4 Count all elbows inside
and outside house.

5 Desired pipe size?

6

What is the altitude of the furnace installation?

Find max intake or

7

exhaust pipe length. Includes all vent pipe and

elbows inside and outside

the house.

FIGURE 25

Page 24

TABLE 13

Maximum Allowable Intake or Exhaust Vent Length in Feet

NOTE – Size intake and exhaust pipe length separately. Values in table are for Intake OR Exhaust, not combined total. Both Intake and Exhaust must be same pipe size.

NOTE – Additional vent pipe and elbows used to terminate the vent pipe outside the structure must be included in the total vent length calculation.

Standard Termination at Elevation 0 – 4500 ft

1-1/2″ Pipe

2″ Pipe

2-1/2″ Pipe

3″ Pipe

No. Of 90°

Model

Model

Model

Model

Elbows 030 045 070

090

110

030/ 045

070

090

110

030/, 045

070

090

110

030/, 045

070

090

110

1

25 20 15

81 66 44 24 115 115 93 58 138 137 118 118

2

20 15 10

76 61 39 19 110 110 88 53 133 132 113 113

3

15 10

71 56 34 14 105 105 83 48 128 127 108 108

4

10

66 51 29

100 100 78 43 123 122 103 103

5

61 46 24

95 95 73 38 118 117 98

98

n/a n/a

6

56 41 19

90 90 68 33 113 112 93

93

n/a

7

n/a

51 36 14 n/a 85 85 63 28 108 107 88

88

n/a

8

46 31

80 80 58 23 103 102 83

83

9

41 26 n/a

75 75 53 18 98 97

78

78

10

36 21

70 70 48 13 93 92

73

73

Standard Termination Elevation 4500 – 10,000 ft

1-1/2″ Pipe

2″ Pipe

2-1/2″ Pipe

3″ Pipe

No. Of 90°

Model

Model

Model

Model

Elbows 030 045 070

090

110

030, 045

070

090

110

030, 045

070

090

110

030, 045

070

090

110

1

25 20 15

81 66 44

115 115 93 58 138 137 118 118

2

20 15 10

76 61 39

110 110 88 53 133 132 113 113

3

15 10

71 56 34

105 105 83 48 128 127 108 108

4

10

66 51 29

100 100 78 43 123 122 103 103

5

61 46 24

95 95 73 38 118 117 98

98

n/a n/a

n/a

6

56 41 19

90 90 68 33 113 112 93

93

n/a

7

n/a

51 36 14

85 85 63 28 108 107 88

88

n/a

8

46 31

80 80 58 23 103 102 83

83

9

41 26 n/a

75 75 53 18 98 97

78

78

10

36 21

70 70 48 13 93 92

73

73

Page 25

TABLE 12 Continued

Maximum Allowable Intake or Exhaust Vent Length in Feet
NOTE – Size intake and exhaust pipe length separately. Values in table are for Intake OR Exhaust, not combined total. Both Intake and Exhaust must be same pipe size. NOTE – additional vent pipe and elbows used to terminate the vent pipe outside the structure must be included in the total vent length calculation.

Concentric Termination at Elevation 0 – 4500 ft

1-1/2″ Pipe

2″ Pipe

2-1/2″ Pipe

3″ Pipe

No. Of 90°

Model

Model

Model

Model

Elbows 030

045

070

090

110

030 045

070

090

110

030 045

070

090

110

030 045

070

090

110

1

20 15 10

73 58 42 22 105 105 89 54 121 121 114 114

2

15 10

68 53 37 17 100 100 84 49 116 116 109 109

3

10

63 48 32 12 95 95 79 44 111 111 104 104

4

58 43 27

90 90 74 39 106 106 99 99

5

53 38 22

85 85 69 34 101 101 94 94

n/a n/a

6

n/a

48 33 17

80 80 64 29 96 96 89 89

n/a

7

n/a

43 28 12 n/a 75 75 59 24 91 91 84 84

8

38 23

70 70 54 19 86 86 79 79

9

33 18 n/a

65 65 49 14 81 81 74 74

10

28 13

60 60 44 n/a 76 76 69 69

Concentric Termination Elevation 4500 – 10,000 ft

1-1/2″ Pipe

2″ Pipe

2-1/2″ Pipe

3″ Pipe

No. Of 90°

Model

Model

Model

Model

Elbows 030

045

070

090

110

030 045

070

090

110

030 045

070

090

110

030 045

070

090

110

1

20 15 10

73 58 42

105 105 89 54 121 121 114 114

2

15 10

68 53 37

100 100 84 49 116 116 109 109

3

10

63 48 32

95 95 79 44 111 111 104 104

4

58 43 27

90 90 74 39 106 106 99 99

5

53 38 22

85 85 69 34 101 101 94 94

n/a n/a

n/a

6

n/a

48 33 17

80 80 64 29 96 96 89 89

n/a

7

n/a

43 28 12

75 75 59 24 91 91 84 84

8

38 23

70 70 54 19 86 86 79 79

9

33 18 n/a

65 65 49 14 81 81 74 74

10

28 13

60 60 44 n/a 76 76 69 69

Page 26

TABLE 14

Maximum Allowable Exhaust Vent Lengths With Furnace Installed in a Closet or Basement Using Ventilated Attic or Crawl Space For Intake Air in Feet

NOTE – Additional vent pipe and elbows used to terminate the vent pipe outside the structure must be included in the total vent length calculation.

Standard Termination at Elevation 0 – 4500 ft

1-1/2″ Pipe

2″ Pipe

2-1/2″ Pipe

3″ Pipe

No Of 90°

Model

Model

Model

Model

Elbows 030

045

070

090

110

030 045

070

090

110

030 045

070

090

110

030 045

070

090

110

1

20 15 10

71 56 34 14 100 100 78 43 118 117 98 98

2

15 10

66 51 29 9 95 95 73 38 113 112 93 93

3

10

61 46 24 4 90 90 68 33 108 107 88 88

4

56 41 19

85 85 63 28 103 102 83 83

5

51 36 14

80 80 58 23 98 97 78 78

n/a n/a

6

n/a

46 31 9

75 75 53 18 93 92 73 73

n/a

7

n/a

41 26 4 n/a 70 70 48 13 88 87 68 68

8

36 21

65 65 43 8 83 82 63 63

9

31 16 n/a

60 60 38 3 78 77 58 58

10

26 11

55 55 33 n/a 73 72 53 53

Standard Termination Elevation 4500 – 10,000 ft

1-1/2″

2″ Pipe

2-1/2″ Pipe

3″ Pipe

No Of 90°

Model

Model

Model

Model

Elbows 030

045

070

090

110

030 045

070

090

110

030 045

070

090

110

030 045

070

090

110

1

20 15 10

71 56 34

100 100 78 43 118 117 98 98

2

15 10

66 51 29

95 95 73 38 113 112 93 93

3

10

61 46 24

90 90 68 33 108 107 88 88

4

56 41 19

85 85 63 28 103 102 83 83

5

51 36 14

80 80 58 23 98 97 78 78

n/a n/a

n/a

6

n/a

46 31 9

75 75 53 18 93 92 73 73

n/a

7

n/a

41 26 4

70 70 48 13 88 87 68 68

8

36 21

65 65 43 8 83 82 63 63

9

31 16 n/a

60 60 38 3 78 77 58 58

10

26 11

55 55 33 n/a 73 72 53 53

Page 27

TYPICAL EXHAUST AND INTAKE PIPE CONNECTIONS IN UPFLOW

DIRECT OR NON-DIRECT VENT APPLICATIONS

2″

EXHAUST INTAKE

EXHAUST INTAKE

2″

2″

2″

or

2″

2″ 3″

3″

Exhaust
DO NOT transition from larger to smaller pipe in horizontal runs
of exhaust pipe.

Exhaust
DO NOT transition from smaller to larger pipe in horizontal runs
of exhaust pipe.

030/045/070 Only
1-1/2″ TRANSITION

2″

6″ Min

Exhaust

  • When transitioning up in pipe size, use the shortest length of 2″ PVC pipe possible. NOTE – Exhaust pipe and intake pipe must be the same diameter.
    FIGURE 26

TYPICAL EXHAUST AND INTAKE PIPE CONNECTIONS IN HORIZONTAL DIRECT OR NON-DIRECT VENT APPLICATIONS (RIGHT HAND DISCHARGE SHOWN)

12″ max.

45° MAX

45° MAX

EXHAUST

2″

or

2″

Exhaust

2″ 2″ INTAKE

2″ 2″

2″ or
2″ 2″

DO NOT transition 2″ from smaller to larger
pipe in horizontal runs of exhaust pipe.

SIDE VIEW

Exhaust
3″

2″ EXHAUST
2″
INTAKE

3″
2″ 2″

030/045/070 Only

DO NOT transition

from larger to smaller 1-1/2″

pipe in horizontal runs

TRANSITION

of exhaust pipe.
*2″

*2″
Exhaust

  • When transitioning up in pipe size, use the shortest length of 2″ PVC pipe possible. NOTE – Exhaust pipe and intake pipe must be the same diameter.

FIGURE 27

Page 28

Intake Piping
The EL196UHE furnace may be installed in either direct vent or non-direct vent applications. In non-direct vent applications, when intake air will be drawn into the furnace from the surrounding space, the indoor air quality must be considered and guidelines listed in Combustion, Dilution and Ventilation Air section must be followed.
Follow the next two steps when installing the unit in Direct Vent applications, where combustion air is taken from outdoors and flue gases are discharged outdoors. The provided air intake screen must not be used in direct vent applications (outdoors).
1 – Use transition solvent cement or a sheet metal screw to secure the intake pipe to the inlet air connector.
2 – 2 – Route piping to outside of structure. Continue with installation following instructions given in general guidelines for piping terminations and intake and exhaust piping terminations for direct vent sections. Refer to TABLE 13 for pipe sizes.
Follow the next two steps when installing the unit in NonDirect Vent applications where combustion air is taken from indoors and flue gases are discharged outdoors.
1 – Use field-provided materials and the factoryprovided air intake screen to route the intake piping as shown in FIGURE 28 or FIGURE 29. Maintain a minimum clearance of 3″ (76mm) around the air intake opening. The air intake opening (with the protective screen) should always be directed forward or to either side in the upflow position, and either straight out or downward in the horizontal position.The air intake piping must not terminate too close to the flooring or a platform. Ensure that the intake air inlet will not be obstructed by
loose insulation or other items that may clog the
debris screen.
2 – If intake air is drawn from a ventilated attic (FIGURE 30) or ventilated crawlspace (FIGURE 31) the exhaust vent length must not exceed those listed in TABLE 6. If 3″ diameter pipe is used, reduce to 2″ diameter pipe at the termination point to accommodate the debris screen.
3 – Use a sheet metal screw to secure the intake pipe to the connector, if desired.

TYPICAL AIR INTAKE PIPE CONNECTIONS UPFLOW NON-DIRECT VENT APPLICATIONS

Min 2″

INTAKE DEBRIS SCREEN (Provided)

NOTE – Debris screen and elbow may be rotated, so that screen may be positioned to face forward or to either side.
FIGURE 28
TYPICAL AIR INTAKE PIPE CONNECTIONS HORIZONTAL NON-DIRECT VENT APPLICATIONS (Horizontal Right-Hand Air Discharge Application Shown)
PVC pipe coupling
Min 2″ OR
INTAKE DEBRIS SCREEN (Provided) NOTE – Debris screen may be positioned straight out (preferred) or with an elbow rotated to face down.
FIGURE 29

Page 29

CAUTION
If this unit is being installed in an application with combustion air coming in from a space serviced by an exhaust fan, power exhaust fan, or other device which may create a negative pressure in the space, take care when sizing the inlet air opening. The inlet air opening must be sized to accommodate the maximum volume of exhausted air as well as the maximum volume of combustion air required for all gas appliances serviced by this space.

EQUIPMENT IN CONFINED SPACE (Inlet Air from Ventilated Attic and Outlet Air to Outside)

Roof Terminated Exhaust Pipe

Ventilation Louvers
Inlet Air (Minimum 12 in.(305mm) Above attic floor)

*Intake Debris Screen
(Provided)
Furnace

NOTE-The inlet and outlet air openings shall each have a free area of at least one square inch per 4,000 Btu (645mm2 per 1.17kW) per hour of the total input rating of all equipment in the enclosure.
FIGURE 30
EQUIPMENT IN CONFINED SPACE (Inlet Air from Ventilated Crawlspace and Outlet Air to Outside)
Roof Terminated Exhaust Pipe

Ventilation

Louvers

Furnace

(Crawl space)

Inlet Air (Minimum 12 in.(305mm) Above crawl space floor)

Coupling or 3 in. to 2 in. Transition (Field Provided)

*Intake Debris Screen Provided)

NOTE-The inlet and outlet air openings shall each have a free area of at least one square inch per 4,000 Btu (645mm2 per 1.17kW) per hour of the total input rating of all equipment in the enclosure.
FIGURE 31

General Guidelines for Vent Terminations
In Non-Direct Vent applications, combustion air is taken from indoors and the flue gases are discharged to the outdoors. The EL196UHE is then classified as a non-direct vent, Category IV gas furnace.
In Direct Vent applications, combustion air is taken from outdoors and the flue gases are discharged to the outdoors. The EL196UHE is then classified as a direct vent, Category IV gas furnace.
In both Non-Direct Vent and Direct Vent applications, the vent termination is limited by local building codes. In the absence of local codes, refer to the current National Fuel Gas Code ANSI Z223-1/NFPA 54 in U.S.A., and current CSAB149 Natural Gas and Propane Installation Codes in Canada for details. Position termination according to location given in FIGURE 33 or FIGURE 34. In addition, position termination so it is free from any obstructions and 12″ above the average snow accumulation.
At vent termination, care must be taken to maintain protective coatings over building materials (prolonged exposure to exhaust condensate can destroy protective coatings). It is recommended that the exhaust outlet not be located within 6 feet (1.8m) of a condensing unit because the condensate can damage the painted coating. NOTE – See TABLE 15 for maximum allowed exhaust pipe length without insulation in unconditioned space during winter design temperatures below 32°F (0°C). If required exhaust pipe should be insulated with 1/2″ (13mm) Armaflex or equivalent. In extreme cold climate areas, 3/4″ (19mm) Armaflex or equivalent may be necessary. Insulation must be protected from deterioration. Armaflex with UV protection is permissable. Basements or other enclosed areas that are not exposed to the outdoor ambient temperature and are above 32 degrees F (0°C) are to be considered conditioned spaces.
IMPORTANT
Do not use screens or perforated metal in exhaust or intake terminations. Doing so will cause freezeups and may block the terminations.
IMPORTANT
For Canadian Installations Only:
In accordance to CSA International B149 installation codes, the minimum allowed distance between the combustion air intake inlet and the exhaust outlet of other appliances shall not be less than 12 inches (305mm).

Page 30

TABLE 15

Maximum Allowable Exhaust Vent Pipe Length (in ft.)3 Without Insulation In Unconditioned Space For Winter Design Temperatures Single – Stage High Efficiency Furnace

Winter Design Temp1 °F (°C)

Vent Pipe Diam

030

Unit Input Size

045

070

090

110

PVC 2PP PVC

2PP

PVC

2PP

PVC 2PP PVC

2PP

32 to 21 (0 to -6)

1-1/2 in 2 in
2-1/2 in

25

N/A

20

N/A

N/A

N/A

N/A

N/A

18

16

31

28

50

48

30

30

13

N/A

24

N/A

42

N/A

56

N/A

3 in

9

9

18

18

35

35

47

47

1-1/2 IN

15

N/A

20

N/A

N/A

N/A

N/A

N/A

20 to 1

2 in

9

N/A

N/A

(-7 to -17) 2-1/2 in

5

8

18

16

32

29

30

30

N/A

13

N/A

24

N/A

34

N/A

3 in

1

1

8

8

19

19

26

26

1-1/2 in

10

N/A

15

N/A

N/A

N/A

N/A

N/A

0 to -20

2 in

5

3

12

10

22

19

30

27

(-18 to -29) 2-1/2 in

1

N/A

7

N/A

15

N/A

22

N/A

3 in

N/A

N/A

2

2

10

10

16

16

1Refer to 99% Minimum Design Temperature table provided in the current edition of the ASHRAE Fundamentals Handbook.

2 Poly-Propylene vent pipe (PP) by Duravent and Centrotherm.

NOTE – Concentric terminations are the equivalent of 5′ and should be considered when measuring pipe length.

NOTE – Maximum uninsulated vent lengths listed may include the termination(vent pipe exterior to the structure) and cannot exceed 5 linear feet or the maximum allowable intake or exhaust vent length listed in table 5 or 6 which ever is less.

NOTE – If insulation is required in an unconditioned space, it must be located on the pipe closest to the furnace. See FIGURE 32.

3 Vent length in the table is equivalent length. Each elbow is equivalent to 5ft of straight pipe and should be included when measuring total length.

Conditioned Space

Conditioned Space

Pipe Insulation
Unconditioned Space

Exhaust Pipe
Intake Pipe

FIGURE 32

Page 31

VENT TERMINATION CLEARANCES FOR NON-DIRECT VENT INSTALLATIONS IN THE USA AND CANADA
INSIDE CORNER DETAIL
G

D E B

H A

L

C

B

B

I

Fixed

Fixed

Operable

Closed

M

Closed

F

Operable

B

K

A

J

B

VENT TERMINAL

AIR SUPPLY INLET

AREA WHERE TERMINAL IS NOT PERMITTED

US Installations1

Canadian Installations2

A =

Clearance above grade, veranda,

porch, deck or balcony

12 inches (305mm) or 12 in. (305mm) above average snow accumulation.

12 inches (305mm) or 12 in. (305mm) above average snow accumulation.

B =

Clearance to window or

door that may be opened

C =

Clearance to permanently

closed window

4 feet (1.2 m) below or to side of opening; 1 foot (30cm) above opening

  • 12″

6 inches (152mm) for appliances <10,000 Btuh (3kw), 12 inches (305mm) for appliances > 10,000 Btuh (3kw) and
<100,000 Btuh (30kw), 36 inches (.9m) for appliances > 100,000 Btuh (30kw)

  • 12″

D = Vertical clearance to ventilated soffit located above the terminal within a
horizontal distance of 2 feet (610 mm) from the center line of the terminal

E =

Clearance to unventilated soffit

  • Equal to or greater than soffit depth.

  • Equal to or greater than soffit depth.

  • Equal to or greater than soffit depth.

  • Equal to or greater than soffit depth.

F =

Clearance to outside corner

  • No minimum to outside corner

  • No minimum to outside corner

G = Clearance to inside corner

H =

  • 3 feet (.9m) within a height 15 feet (4.5m) 3 feet (.9m) within a height 15 feet (4.5m)

tended above meter / regulator assembly

above the meter / regulator assembly

above the meter / regulator assembly

I =

Clearance to service regulator

vent outlet

  • 3 feet (.9m)

3 feet (.9m)

J =

Clearance to non-mechanical air

pliance
K = ply inlet

4 feet (1.2 m) below or to side of opening; 1 foot (30 cm) above opening
3 feet (.9m) above if within 10 feet (3m) horizontally

6 inches (152mm) for appliances <10,000 Btuh (3kw), 12 inches (305mm) for appliances > 10,000 Btuh (3kw) and
<100,000 Btuh (30kw), 36 inches (.9m) for appliances > 100,000 Btuh (30kw)
6 feet (1.8m)

L = Clearance above paved sidewalk or paved driveway located on public property

7 feet (2.1m)

7 feet (2.1m)

M = Clearance under veranda, porch, deck or balcony

*12 inches (305mm)

12 inches (305mm)

1 In accordance with the current ANSI Z223.1/NFPA 54 Natural Fuel Gas Code 2 In accordance with the current CSA B149.1, Natural Gas and Propane Installation Code A vent shall not terminate directly above a sidewalk or paved driveway that is located between two single family dwellings and serves both dwellings.
Permitted only if veranda, porch, deck or balcony is fully open on a minimum of two sides beneath the floor. Lennox recommends avoiding this location if possible.

*For clearances not specified in ANSI Z223.1/NFPA 54 or CSA B149.1, clearance will be in accordance with local installation codes and the requirements of the lation instructions.” NOTE – This figure is intended to illustrate clearance requirement and does not serve as a substitute for locally adopted installation codes.

FIGURE 33

Page 32

D E B

VENT TERMINATION CLEARANCES FOR DIRECT VENT INSTALLATIONS IN THE US AND CANADA
INSIDE CORNER DETAIL
G

A

H

L

C

B

B

I

Fixed

Fixed

Operable

Closed

M

Closed

F

Operable

B

K

A

J

B

VENT TERMINAL

AIR SUPPLY INLET

AREA WHERE TERMINAL IS NOT PERMITTED

US Installations1

Canadian Installations2

A =

Clearance above grade, veranda,

porch, deck or balcony

12 inches (305mm) or 12 in. (305mm) above average snow accumulation.

12 inches (305mm) or 12 in. (305mm) above average snow accumulation.

B =

Clearance to window or

door that may be opened

C =

Clearance to permanently

closed window

6 inches (152mm) for appliances <10,000 6 inches (152mm) for appliances <10,000

Btuh (3kw), 12 inches (305mm) for

pliances > 10,000 Btuh (3kw) and <50,000 appliances > 10,000 Btuh (3kw) and

<100,000 Btuh (30kw), 36 inches (.9m)

pliances > 50,000 Btuh (15kw)

for appliances > 100,000 Btuh (30kw)

  • 12″

  • 12″

D = Vertical clearance to ventilated soffit located above the terminal within a
horizontal distance of 2 feet (610mm) from the center line of the terminal

  • Equal to or greater than soffit depth * Equal to or greater than soffit depth

E =

Clearance to unventilated soffit

F =

Clearance to outside corner

  • Equal to or greater than soffit depth * No minimum to outside corner

  • Equal to or greater than soffit depth * No minimum to outside corner

G =

Clearance to inside corner

H = tended above meter / regulator assembly

3 feet (.9m) within a height 15 feet (4.5m) 3 feet (.9m) within a height 15 feet (4.5m)

above the meter / regulator assembly

above the meter / regulator assembly

I =

Clearance to service regulator

vent outlet

  • 3 feet (.9m)

3 feet (.9m)

J =

Clearance to non-mechanical air

pliance
K = ply inlet

6 inches (152mm) for appliances <10,000 6 inches (152mm) for appliances <10,000

Btuh (3kw), 12 inches (305mm) for

pliances > 10,000 Btuh (3kw) and <50,000 appliances > 10,000 Btuh (3kw) and

<100,000 Btuh (30kw), 36 inches (.9m)

pliances > 50,000 Btuh (15kw)

for appliances > 100,000 Btuh (30kw)

3 feet (.9m) above if within 10 feet (3m) horizontally

6 feet (1.8m)

L = Clearance above paved sidewalk or paved driveway located on public property

  • 7 feet (2.1m)

7 feet (2.1m)

M = Clearance under veranda, porch, deck or balcony

*12 inches (305mm)

12 inches (305mm)

1 In accordance with the current ANSI Z223.1/NFPA 54 Natural Fuel Gas Code 2 In accordance with the current CSA B149.1, Natural Gas and Propane Installation Code
A vent shall not terminate directly above a sidewalk or paved driveway that is located between two single family dwellings and serves both dwellings. Permitted only if veranda, porch, deck or balcony is fully open on a minimum of two sides beneath the floor. Lennox recommends avoiding this location if possible.

*For clearances not specified in ANSI Z223.1/NFPA 54 or CSA B149.1, clearance will be in accordance with local installation codes and the requirements of the gas supplier and these installation instructions.”
NOTE – This figure is intended to illustrate clearance requirements and does not serve as a substitute for locally adopted installation codes.

FIGURE 34

Page 33

Details of Intake and Exhaust Piping Terminations for
Direct Vent Installations
NOTE – In Direct Vent installations, combustion air is taken from outdoors and flue gases are discharged to outdoors. NOTE – Flue gas may be slightly acidic and may adversely affect some building materials. If any vent termination is used and the flue gasses may impinge on the building material, corrosion- resistant shield (minimum 24 inches square) should be used to protect the wall surface. If the optional tee is used, the protective shield is recommended. The shield should be constructed using wood, plastic, sheet metal or other suitable material. All seams, joints, cracks, etc. in the affected area should be sealed using an appropriate sealant. See FIGURE 34.
Intake and exhaust pipes may be routed either horizontally through an outside wall or vertically through the roof. In attic or closet installations, vertical termination through the roof is preferred. FIGURE 35 through FIGURE 42 show typical terminations.
1 – Intake and exhaust terminations are not required to be in the same pressure zone. You may exit the intake on one side of the structure and the exhaust on another side (FIGURE 36). You may exit the exhaust out the roof and the intake out the side of the structure (FIGURE 37).
2 – Intake and exhaust pipes should be placed as close together as possible at termination end (refer to illustrations). Maximum separation is 3″ (76mm) on roof terminations and 6″ (152mm) on side wall terminations.
NOTE – When venting in different pressure zones, the maximum separation requirement of intake and exhaust pipe DOES NOT apply. 3 – On roof terminations, the intake piping should terminate straight down using two 90° elbows (See FIGURE 35).
4 – Exhaust piping must terminate straight out or up as shown. A reducer may be required on the exhaust piping at the point where it exits the structure to improve the velocity of exhaust away from the intake piping. See TABLE 16.

Inches(mm)

3″(76mm) MAX.

8″ (203mm) MIN
12″ (305mm) ABOVE AVERAGE SNOW ACCUMULATION

UNCONDITIONED ATTIC SPACE

3″ (76mm) OR 2″ (51mm) PVC
PROVIDE SUPPORT FOR INTAKE AND EXHAUST LINES DIRECT VENT ROOF TERMINATION KIT (15F75 or 44J41)
FIGURE 35

NOTE – Care must be taken to avoid recirculation of exhaust back into intake pipe. 5 – On field-supplied terminations for side wall exit, exhaust piping may extend a maximum of 12 inches (305mm) for 2″ PVC and 20 inches (508mm) for 3″ (76mm) PVC beyond the outside wall. Intake piping should be as short as possible. See FIGURE 43.
6 – On field-supplied terminations, a minimum distance between the end of the exhaust pipe and the end of the intake pipe without a termination elbow is 8″ and a minimum distance of 6″ with a termination elbow. See FIGURE 43.
Exiting Exhaust and Intake Vent (different pressure zone)

Exhaust Pipe

Furnace
FIGURE 36

Inlet Air (Minimum 12 in. 305 MM) above grade or snow
accumulation

Exiting Exhaust and Intake Vent (different pressure zone)

Roof Terminated Exhaust Pipe

Furnace

Inlet Air (Minimum 12 in. 305 MM) above grade or snow
accumulation

FIGURE 37

TABLE 16

Exhaust Pipe Termination Size Reduction

EL196UHE Model

Termination Pipe Size

030, 045, *070

1-1/2″ (38mm)

*090 110

2″ (51mm)

*Use the provided 1-1/2″ accelerator if matched with the flushmount termination.

Page 34

7 – If intake and exhaust piping must be run up a side wall to position above snow accumulation or other obstructions, piping must be supported. At least one bracket must be used within 6″ from the top of the elbow and then every 24″ (610mm) as shown in FIGURE 43, to prevent any movement in any direction. When exhaust and intake piping must be run up an outside wall, the exhaust piping must be terminated with pipe sized per TABLE 16. The intake piping may be equipped with a 90° elbow turndown. Using turndown will add 5 feet (1.5m) to the equivalent length of the pipe.
8 – A multiple furnace installation may use a group of up to four terminations assembled together horizontally, as shown in FIGURE 41.

2″ EXTENSION FOR 2″ PVC PIPE1″ EXTENSION FOR 3″ PVC PIPE
4”

FURNACE EXHAUST
PIPE

FURNACE INTAKE PIPE

GLUE EXHAUST END FLUSH INTO
TERMINATION

FLAT SIDE

1-1/2″ ACCELERATOR

FLUSH-MOUNT SIDE WALL TERMINATION KIT 51W11 (US) or 51W12 (Canada)
FIGURE 38

12″ (305mm)
Minimum Above Average
Snow Accumulation

Accelerator not required for 3″ concentric

INTAKE

FLASHING (Not Furnished)

CLAMP

SHEET METAL STRAP (Clamp and sheet metal strap must be field installed to support the weight of the termination kit.)
FIELD-PROVIDED REDUCER MAY BE REQUIRED
TO ADAPT DIFFERENT VENT PIPE SIZE TO TERMINATION

DIRECT VENT CONCENTRIC ROOFTOP TERMINATION 71M80, 69M29 or 60L46 (US) 44W92 or 44W93 (Canada)
FIGURE 39

FIELD-PROVIDED REDUCER MAY BE REQUIRED TO ADAPT DIFFERENT VENT PIPE SIZE TO TERMINATION OUTSIDE
WALL
EXHAUST AIR

Accelerator not required for 3″ concentric
INTAKE AIR EXHAUST AIR

INTAKE AIR

CLAMP (Not Furnished)

INTAKE 12″ (305mm) Min. AIR above grade or average snow ac cumulation. GRADE

DIRECT VENT CONCENTRIC WALL TERMINATION 71M80, 69M29 or 60L46 (US) 44W92 or 44W93 (Canada)

FIGURE 40

EXHAUST VENT
INTAKE AIR
Inches (mm)

5″ (127mm)

12″ (305mm) 5-1/2″ (140mm)

18″ MAX. (457mm)

Front View

EXHAUST VENT 12″ (305mm) Min. above grade or

INTAKE cumulation. AIR

optional intake elbow

Side View

OPTIONAL VENT TERMINATION FOR MULTIPLE UNIT INSTALLATION OF DIRECT VENT WALL TERMINATION KIT

(30G28 or 81J20)

FIGURE 41

DIRECT VENT APPLICATION USING EXISTING CHIMNEY

STRAIGHT-CUT OR ANGLE-CUT IN DIRECTION
OF ROOF SLOPE *

8″ – 12″ (203mm – 305mm)

3″ – 8″ (76mm203mm)

Minimum 12″ (305MM) above chimney top
plate or average snow accumulation

INTAKE PIPE INSULATION (optional)
SHEET METAL TOP
PLATE

INSULATE TO FORM
SEAL

SHOULDER OF FITTINGS PROVIDE SUPPORT
OF PIPE ON TOP PLATE
ALTERNATE INTAKE PIPE

3″ – 8″ (76mm203mm)

EXTERIOR PORTION OF
CHIMNEY

NOTE – Do tical discharge through an existing unused chimney or stack is required, insert piping inside trated. In any exterior portion of chimney, the exhaust vent must be insulated.
FIGURE 42

Page 35

NOTE – FIELD-PROVIDED REDUCER MAY BE
REQUIRED TO ADAPT LARGER VENT PIPE SIZE
TO TERMINATION
D

FIELD FABRICATED WALL TERMINATION

A- Minimum clearance

above grade or average

snow accumulation

D

B- Maximum horizontal

separation between

intake and exhaust

2″ (51mm) Vent Pipe
12″ (305 mm)
6″ (152 mm)

3″ (76mm) Vent Pipe
12″ (305 mm)
6″ (152 mm)

B

B

C1

Intake Elbow C2

C1 -Minimum from end of exhaust to inlet of intake 8″ (203 mm) 8″ (203 mm)

A

STRAIGHT

A

APPPLICATION

C2 -Minimum from end of exhaust to inlet of intake 6″ (152 mm) 6″ (152 mm)

  • WALL SUPPORT

D- Maximum exhaust pipe length

12″ (305 mm) 20″ (508 mm)

D E

E

D

E- Maximum wall support distance from top of each 6″ (152 mm) 6″ (152 mm)

pipe (intake/exhaust)

See maximum allowable venting tables for venting

B

B

lengths with this arrangement.

  • Use wall support every 24″ (610 mm). Use two

C1

A

wall supports if extension is greater than

C2

A

24″ (610 mm) but less than 48″ (1219 mm).

EXTENDED APPLICATION

NOTE – One wall support must be within 6″ (152 mm) from top of each pipe (intake and exhaust) to prevent movement in any direction.

ALTERNATE TERMINATIONS (TEE & FORTY-FIVE DEGREE ELBOWS ONLY)

B

D

C 2
A

D
E B
C 2
A

2″ (51mm)

3″ (76mm)

Vent Pipe

Vent Pipe

B

Exhaust

A – Clearance above Grade or average snow

12″ (305 mm) Min 12″ (305 mm) Min

1

D

accumulation B – Horizontal separation

6″ (152mm)min 6″ (152mm)min

between intake and exhaust 24″ (610mm )Max 24″ (610mm )Max

Intake Elbow

C A

3

C – Minimum from end of

9″ (227mm)

9″ (227mm)

exhaust to inlet of intake

D – Exhaust pipe length

12″ (305mm)min 12″ (305mm)min 16″ (405mm )Max 16″ (405mm )Max

D 1
E

E – Wall support distance from 6″ (152mm) Max top of each pipe (intake/exhaust)

6″ (152mm) Max

B 1

E

D

B 12″

Front View of Intake and Exhaust

C

12″

2

A

C

Intake

Exhaust

A

1The exhaust termination tee should be connected to the 2″ or 3″ PVC flue pipe as shown in the illustration. In horizontal tee applications there must be be a minimum of 3 ft away from covered patios or any living ares and cannot be within 3 ft of a window. Do not use an accelerator in applications that include an exhaust termination tee. The accelerator is not required.
2 As required. Flue gas may be acidic and may adversely affect some building materials. If a side wall vent termination is used and flue gases will impinge on the building materials, a corrosion-resistant shield (24 inches square) should be used to protect the wall surface. If optional tee is used, the protective shield
is recommended. The shield should be constructed using wood, sheet metal or other suitable material. All seams, joints, cracks, etc. in affected area, should be sealed using an appropriate sealant. 3 Exhaust pipe 45° elbow can be rotated to the side away from the combustion air inlet to direct exhaust away from adjacent property. The exhaust must never be directed toward the combustion air inlet.

FIGURE 43

Page 36

Details of Exhaust Piping Terminations for Non-Direct Vent Applications
Exhaust pipes may be routed either horizontally through an outside wall or vertically through the roof. In attic or closet installations, vertical termination through the roof is preferred. FIGURE 44 and FIGURE 45 show typical terminations.
1 – Exhaust piping must terminate straight out or up as shown. The termination pipe must be sized as listed in table 16.The specified pipe size ensures proper velocity required to move the exhaust gases away from the building.
2 – On field supplied terminations for side wall exit, exhaust piping may extend a maximum of 12 inches (305mm) for 2″ PVC and 20 inches (508mm) for 3″ (76mm) PVC beyond the outside wall.
3 – If exhaust piping must be run up a side wall to position above snow accumulation or other obstructions, piping must be supported every 24 inches (610mm). When exhaust piping must be run up an outside wall, any reduction in exhaust pipe size must be done after the final elbow.
4 – Distance between exhaust pipe terminations on multiple furnaces must meet local codes.
12″ (305mm) ABOVE AVE.
SNOW ACCUMULATION

3″ (76mm) OR 2″ (51mm) PVC
PROVIDE SUPPORT FOR EXHAUST LINES

UNCONDITIONED ATTIC SPACE

NON-DIRECT VENT ROOF TERMINATION KIT (15F75 or 44J41)
FIGURE 44

NON-DIRECT VENT APPLICATION USING EXISTING CHIMNEY
STRAIGHT-CUT OR ANGLE-CUT IN DIRECTION
OF ROOF SLOPE

Minimum 12″ (305MM) above chimney top
plate or average snow accumulation
SHEET METAL TOP
PLATE
INSULATE TO FORM
SEAL

SHOULDER OF FITTINGS PROVIDE SUPPORT
OF PIPE ON TOP PLATE
EXTERIOR PORTION OF
CHIMNEY

NOTE – Do tical discharge through an existing unused chimney or stack is required, insert piping inside trated. In any exterior portion of chimney, the exhaust vent must be insulated.
FIGURE 45
Condensate Piping
This unit is designed for either right- or left-side exit of condensate piping in upflow applications. In horizontal applications, the condensate trap must extend below the unit. An 8″ service clearance is required for the condensate trap.
Refer to FIGURE 46 and FIGURE 48 for condensate trap locations. FIGURE 54 shows trap assembly using 1/2″ PVC or 3/4″ PVC. NOTE – If necessary the condensate trap may be installed up to 5′ away from the furnace. Use PVC pipe to connect trap to furnace condensate outlet. Piping from furnace must slope down a minimum of 1/4″ per ft. toward trap.
1 – Determine which side condensate piping will exit the unit, location of trap, field-provided fittings and length of PVC pipe required to reach available drain.
2 – Use a large flat head screw driver or a 1/2″ drive socket extension and remove plug (figure 46) from the cold end header box at the appropriate location on the side of the unit. Install provided 3/4 NPT street elbow fitting into cold end header box. Use Teflon tape or appropriate pipe dope.

Page 37

NOTE – Cold end header box drain plugs are factory installed. Check the unused plug for tightness to prevent leakage. 3 – Install the cap over the clean out opening at the base of the trap. Secure with clamp. See FIGURE 54. 4 – Install drain trap using appropriate PVC fittings, glue all joints. Glue the provided drain trap as shown in FIGURE 54. Route the condensate line to an open drain. Condensate line must maintain a 1/4″ downward slope from the furnace to the drain.
CONDENSATE TRAP AND PLUG LOCATIONS (Unit shown in upflow position)
Trap (same on right side)
1-1/2 in.
Plug (same on left side)
NOTE – In upflow applications where side return
sate trap, filter rack must be installed beyond condensate trap or trap must be re-located to avoid interference.
FIGURE 46 5 – FIGURE 49 and FIGURE 51 shows the furnace and
evaporator coil using a separate drain. If necessary the condensate line from the furnace and evaporator coil can drain together. See FIGURE 50, FIGURE 52 and FIGURE 53.
Upflow furnace (FIGURE 52) – In upflow furnace applications the field provided vent must be a minimum 1″ to a maximum 2″ length above the condensate drain outlet connection. Any length above 2″ may result in a flooded heat exchanger if the combined primary drain line were to become restricted.

Horizontal furnace (FIGURE 53) In horizontal furnace applications the field provided vent must be a minimum 4″ to a maximum 5″ length above the condensate drain outlet connection. Any length above 5″ may result in a flooded heat exchanger if the combined primary drain line were to become restricted. NOTE – In horizontal applications it is recommended to install a secondary drain pan underneath the unit and trap assembly. NOTE – Appropriately sized tubing and barbed fitting may be used for condensate drain. Attach to the drain on the trap using a hose clamp. See FIGURE 47.
Field Provided Drain Components

Elbow

Tubing

Barbed Fitting Hose Clamp

FIGURE 47
CAUTION
Do not use copper tubing or existing copper condensate lines for drain line.
6 – If unit will be started immediately upon completion of installation, prime trap per procedure outlined in Unit Start-Up section.
Condensate line must slope downward away from the trap to drain. If drain level is above condensate trap, condensate pump must be used. Condensate drain line should be routed within the conditioned space to avoid freezing of condensate and blockage of drain line. If this is not possible, a heat cable kit may be used on the condensate trap and line. Heating cable kit is available from Lennox in various lengths; 6 ft. (1.8m) kit no. 26K68 and 24 ft. (7.3m) – kit no. 26K69.

Page 38

CONDENSATE TRAP LOCATIONS (Unit shown in upflow position with remote trap)
Field ProvidedVent Min. 1″ Above Condensate
Drain Connection
1″ Min. 2″ Max.
*5′ max. PVC PipeOnly
Trap Can Be Installed a Maximum 5′ From Furnace

Condensate Trap With Optional Overflow Switch

From Evaporator Coil

HorizontalFurnace4″ Min. to 5″ Max.above condensatedrain connection)

Optional

FurnaceCondensate Drain Connection

To Drain

*Piping from furnace must slope down a minimum 1/4″ per ft. toward trap
FIGURE 48
Furnace With Evaporator Coil Using A Separate Drain

(Trap at coil is optional)
Field Provided Vent (1″ min. 2″ max. above condensate connection)
Condensate Drain Connection

Evaporator drain line required

FIGURE 50

FIGURE 49

Page 39

Furnace with Evaporator Coil Using a Separate Drain (Unit shown in horizontal left-hand discharge position)

Evaporator Coil

4″min 5″max
5′ max. PVC Pipe Only
Condensate Drain Connection

Field Provided Vent (4″ min. to 5″ max. above condensate connection)

Drain Pan

(Trap at coil is optional)
Piping from furnace and evaporator coil must slope down a minimum 1/4″ per ft. toward trap .
FIGURE 51

Furnace with Evaporator Coil Using a Common Drain
Evaporator drain line required
(Trap at coil is optional)
(1″ min. to 2″ Max.above condensatedrain connection)
Condensate Drain Connection

IMPORTANT
When combining the furnace and evaporator coil drains together, the A/C condensate drain outlet must be vented to relieve pressure in order for the furnace pressure switch to operate properly.

FIGURE 52
Furnace with Evaporator Coil Using a Common Drain (Unit shown in horizontal left-hand discharge position)

Drain Pan

Evaporator Coil

4″min 5″max
5′ max. PVC Pipe Only
Condensaet Drain Connection

(Trap at coil is optional)
Piping from furnace and evaporator coil must slope down a minimum 1/4″ per ft. toward trap
FIGURE 53

Page 40

(4″ min. to 5″ Max.above condensatedrain connection)

TRAP / DRAIN ASSEMBLY USING 1/2″ PVC OR 3/4″ PVC Optional Condensate Drain Connection

Adapter 3/4 inch slip X 3/4 inch mpt (not furnished)

90° Street Elbow 3/4 inch PVC (not furnished)

90° Street Elbow 3/4 inch PVC ( furnished)

Condensate Drain Connection In Unit

To Trap

Optional DrainPiping FromTrap

Adapter 3/4 inch slip X 3/4 inch mpt (not furnished)

1 (25 mm) Min. 2 (50 mm) Max. Above Top Of Condensate Drain Connection In Unit

Vent

5 Feet Maximum

Condensate Drain Connection In Unit

90° Elbow 3/4 inch PVC (Not Furnished)
1/2 inch PVC Pipe (Not Furnished)

3/4 inch PVC Pipe (Not Furnished)

Drain Assembly for 1/2 inch Drain Pipe

Coupling 3/4 inch slip X slip (Not Furnished)

1/2 inch PVC Pipe (Not Furnished)

To Drain

90° Elbow 1/2 inch PVC (Not Furnished)

Drain Assembly for 3/4 inch Drain Pipe

Drain Trap Assembly (Furnished)

90° Elbow 3/4 inch PVC (Not Furnished)

90° Elbow
3/4 inch PVC (Not Furnished)

Drain Trap Clean Out

To Drain
DrainTrap Assembly (Furnished)

To Coupling 3/4 inch slip X slip

Drain

(Not Furnished)

DrainTrap Assembly with 1/2 inch Piping
1 (25 mm) Min. 2 (50 mm) Max. Above Top Of Condensate Drain Connection In Unit
Vent

DrainTrap Assembly with 3/4 inch Piping
1 (25 mm) Min. 2 (50 mm) Max. Above Top Of Condensate Drain Connection In Unit
Vent

7 (178)

1/2 inch

Condensate Drain Connection In Unit

3/4 inch

Condensate Drain Connection In Unit

To Drain

FIGURE 54

To Drain

Page 41

III-START-UP
A-Preliminary and Seasonal Checks
1 – Inspect electrical wiring, both field and factory installed for loose connections. Tighten as required.
2 – Check voltage at disconnect switch. Voltage must be within range listed on the nameplate. If not, consult the power company and have voltage condition corrected before starting unit.
3 – Inspect condition of condensate traps and drain assembly. Disassemble and clean seasonally.
B-Heating Start-Up
BEFORE LIGHTING the unit, smell all around the furnace area for gas. Be sure to smell next to the floor because some gas is heavier than air and will settle on the floor.
The gas valve on the EL196UHE is equipped with a gas control switch. Use only your hand to move the switch. Never use tools. If the the switch will not move by hand, replace the valve. Do not try to repair it. Force or attempted repair may result in a fire or explosion.
Placing the furnace into operation:
EL196UHE units are equipped with a SureLight ignition system. Do not attempt to manually light burners on this furnace. Each time the thermostat calls for heat, the burners will automatically light The ignitor does not get hot when there is no call for heat on units with SureLight ignition system.
Priming Condensate Trap
The condensate trap should be primed with water prior to start-up to ensure proper condensate drainage. Either pour 10 fl. oz. (300 ml) of water into the trap, or follow these steps to prime the trap:
1 – Follow the lighting instructions to place the unit into operation.
2 – Set the thermostat to initiate a heating demand.
3 – Allow the burners to fire for approximately 3 minutes.
4 – Adjust the thermostat to deactivate the heating demand.
5 – Wait for the combustion air inducer to stop. Set the thermostat to initiate a heating demand and again allow the burners to fire for approximately 3 minutes.
6 – Adjust the thermostat to deactivate the heating demand and again wait for the combustion air inducer to stop. At this point, the trap should be primed with sufficient water to ensure proper condensate drain operation.
WARNING
If you do not follow these instructions exactly, a fire or explosion may result causing property damage, personal injury or death.
Gas Valve Operation (FIGURE 55)
1 – STOP! Read the safety information at the beginning of this section.

2 – Set the thermostat to the lowest setting.
3 – Turn off all electrical power to the unit.
4 – This furnace is equipped with an ignition device which automatically lights the burners. Do not try to light the burners by hand.
5 – Remove the upper access panel.
6 – Move gas valve switch to OFF. See FIGURE 55.
7 – Wait five minutes to clear out any gas. If you then smell gas, STOP! Immediately call your gas supplier from a neighbor’s phone. Follow the gas supplier’s instructions. If you do not smell gas go to next step.
8 – Move gas valve switch to ON. See FIGURE 55.

Manifold Pressure Adjustment Screw

Resideo Gas Valve
Manifold Pressure Outlet Port

Inlet Pressure Port GAS VALVE SHOWN IN ON POSITION
FIGURE 55
9 – Replace the upper access panel. 10 – Turn on all electrical power to to the unit. 11 – Set the thermostat to desired setting.
NOTE – When unit is initially started, steps 1 through 11 may need to be repeated to purge air from gas line. 12 – If the appliance will not operate, follow the instructions “Turning Off Gas to Unit” and call your service technician or gas supplier.
Turning Off Gas to Unit
1 – Set the thermostat to the lowest setting. 2 – Turn off all electrical power to the unit if service is to
be performed. 3 – Remove the upper access panel. 4 – Move gas valve switch to OFF. 5 – Replace the upper access panel.
Failure To Operate If the unit fails to operate, check the following:
1 – Is the thermostat calling for heat? 2 – Are access panels securely in place? 3 – Is the main disconnect switch closed? 4 – Is there a blown fuse or tripped breaker? 5 – Is the filter dirty or plugged? Dirty or plugged filters
will cause the limit control to shut the unit off. 6 – Is gas turned on at the meter? 7 – Is the manual main shut-off valve open? 8 – Is the internal manual shut-off valve open? 9 – Is the unit ignition system in lockout? If the unit
locks out again, inspect the unit for blockages.

Page 42

IV-HEATING SYSTEM SERVICE CHECKS
A-C.S.A. Certification
All units are C.S.A. design certified without modifications. Refer to the EL196UHE Operation and Installation Instruction Manual Information. B-Gas Piping
IMPORTANT
If a flexible gas connector is required or allowed by the authority that has jurisdiction, black iron pipe shall be installed at the gas valve and extend outside the furnace cabinet. The flexible connector can then be added between the black iron pipe and the gas supply line.
Gas supply piping should not allow more than 0.5″W.C. drop in pressure between gas meter and unit. Supply gas pipe must not be smaller than unit gas connection. Compounds used on gas piping threaded joints should be resistant to action of liquefied petroleum gases. C-Testing Gas Piping
IMPORTANT
In case emergency shutdown is required, turn off the main shut-off valve and disconnect the main power to unit. These controls should be properly labeled by the installer.

When pressure testing gas lines, the gas valve must be disconnected and isolated. Gas valves can be damaged if subjected to more than 0.5psig (14″ W.C.). See FIGURE 56.

MANUAL MAIN SHUT-OFF VALVE WILL NOT HOLD
NORMAL TEST PRESSURE
1/8″ N.P.T. PLUGGED TAP

CAP FURNACE ISOLATE
GAS VALVE

FIGURE 56
When checking piping connections for gas leaks, use preferred means. Kitchen detergents can cause harmful corrosion on various metals used in gas piping. Use of a specialty Gas Leak Detector is strongly recommended. It is available through Lennox under part number 31B2001. See Corp. 8411-L10, for further details.
WARNING
Do not use matches, candles, flame or any other source of ignition to check for gas leaks.

D-Testing Gas Supply Pressure Gas Flow(Approximate)

TABLE 17

GAS METER CLOCKING CHART

Seconds for One Revolution

ML193 Unit

Natural

1 cu ft Dial

2 cu ft Dial

LP

1 cu ft Dial

2 cu ft Dial

-030

120

240

300

600

-045

80

160

200

400

-070

55

110

136

272

-090

41

82

102

204

-110

33

66

82

164

Natural-1000 btu/cu ft LP-2500 btu/cu ft

Furnace should operate at least 5 minutes before checking gas flow. Determine time in seconds for two revolutions of gas through the meter. (Two revolutions assures a more accurate time.) Divide by two and compare to time in TABLE 17. If manifold pressure matches TABLE 19 and rate is incorrect, check gas orifices for proper size and restriction. Remove temporary gas meter if installed. NOTE – To obtain accurate reading, shut off all other gas appliances connected to meter.
Supply Pressure Measurement

When testing supply gas pressure, use the 1/8″ N.P.T. plugged tap or pressure post located on the gas valve to facilitate test gauge connection. See FIGURE 55. Check gas line pressure with unit firing at maximum rate. Low pressure may result in erratic operation or underfire. High pressure can result in permanent damage to gas valve or overfire.
On multiple unit installations, each unit should be checked separately, with and without units operating. Supply pressure must fall within range listed in TABLE 19.
Manifold Pressure Measurement

Follow the steps below and use FIGURE 55 as a reference. Gas manifold Kit 10L34 provides additional components if needed.
1 – Connect the test gauge positive side “+” to manifold pressure tap on gas valve.
2 – Tee into the gas valve regulator vent hose and connect to test gauge negative “-“.
3 – Start unit and let run for 5 minutes to allow for steady state conditions.
4 – After allowing unit to stabilize for 5 minutes, record manifold pressure and compare to value given in TABLE 19.
5 – Shut unit off and remove manometer as soon as an accurate reading has been obtained. Take care to replace pressure tap plug.
6 – Start unit and perform leak check. Seal leaks if found.

Page 43

2″ Long Square Tubing
(remove for manifold adjustment)
Gas Valve Regulator Vent Hose
(to burner box)
Barbed Fitting

Negative Barbed Fitting
(remove for manifold adjustment)

(-)

(+)

Manifold Pressure Outlet

Tee
10” Long Square Tubing

Measuring Device

FIGURE 57

E-Proper Combustion

Furnace should operate minimum 15 minutes with correct manifold pressure and gas flow rate before checking combustion. Take combustion sample beyond the flue outlet and compare to the table below. The maximum carbon monoxide reading should not exceed 100 ppm.

EL196 Unit -030 -045 -070 -090 -110

TABLE 18 CO2% Nat
7.5- 8.5

CO2% LP 8.2 – 9.5

F-High Altitude
NOTE – In Canada, certification for installations at elevations over 4500 feet (1372 m) is the jurisdiction of local authorities.
Some units installed at altitude of 4501 – 10,000 feet (1373 to 3048 m) may require a pressure switch change which can be ordered separately and a manifold de-rate. See TABLE 19 for manifold pressures at all altitudes. TABLE 20 lists conversion kit and pressure switch requirements at varying altitudes.
The combustion air pressure switch is factory-set and requires no adjustment.

Page 44

TABLE 19

Manifold and Supply Line Pressure 0-10,000ft.

EL196 Unit

Manifold Pressure in. wg.

Supply Line Pressure

Gas

in. w.g.

0 – 4500 ft 4501 – 5500 ft 5501 – 6500 ft 6501 – 7500 ft 7501 – 10,000 ft

0 – 10000 ft.

All

Natural

3.5

3.3

3.2

3.1

3.5

4.5

13.0

Models L.P. Propane 10.0

9.4

9.1

8.9

10.0

11.0

13.0

NOTE – A natural to L.P. propane gas changeover kit is necessary to convert this unit. Refer to the changeover kit installation instruction for the conversion procedure.

TABLE 20

Conversion Kit and Pressure Switch Requirements at Varying Altitudes

EL196 Model

Natural to LP/ Propane
0 – 7500 ft (0 – 2286m)

High Altitude Natural Burner
Orifice Kit
7501 – 10,000 f t (2286 – 3038m)

High Altitude LP/Propane Burner
Orifice Kit
7501 – 10,000 ft (2286 – 3038m)

High Altitude Pressure Switch

4501 – 7500 ft (1373 – 2286m)

7501 -10,000 ft (2286 – 3048m)

-030

17H63

14C90

17H66

11U66

11U69

-045

11U66

11U69

-070 -090

*11K49

73W37

*11K44

11U70 11U70

11U68 11U64

-110

11U70

11U64

  • Conversion requires installation of a gas valve manifold spring which is provided with the gas conversion kit. Pressure switch is factory set. No adjustment necessary. All models use the factory-installed pressure switch from 0-4500 feet (0-1370 m).

Page 45

G- Proper Ground and Voltage
WARNING
Electric Shock Hazard. Can cause injury or death. Unit must be properly grounded in accordance with national and local codes.
A poorly grounded furnace can contribute to premature ignitor failure. Use the following procedure to check for ground and voltage to the integrated control.
1 – Measure the AC voltage between Line Neutral (spade terminals) and “C” terminal (low voltage terminal block) on the integrated control. See . A wide variation in the voltage between Line Neutral and “C” as a function of load indicates a poor or partial ground. Compare the readings to the table below. If the readings exceed the maximum shown in TABLE 21, make repairs before operating the furnace.
CHECK VOLTAGE BETWEEN LINE NEUTRAL AND LOW VOLTAGE “C” TERMINAL

2 – In addition, measure the AC voltage from Line Hot to Line Neutral (spade terminals) on the integrated control. See FIGURE 58. This voltage should be in the range of 97 to 132 Vac
Note – FIGURE 58 is a typical ignition control illustration.

TABLE 21

Furnace Status

Measurement VAC Expected Maximum

Power On Furnace Idle

0.3

2

CAI / Ignitor Energized

0.75

5

Indoor Blower Energized Less than 2

10

CHECK VOLTAGE BETWEEN LINE HOT AND LINE NEUTRAL

Red LED Recall

Red LED Recall
FIGURE 58 Page 46

V-TYPICAL OPERATING CHARACTERISTICS
A-Blower Operation and Adjustment1
NOTE- The following is a generalized procedure and does not apply to all thermostat controls.
1 – Blower operation is dependent on thermosta control system
2 – Generally, blower operation is set at thermostat subbase fan switch. With fan switch in ON position, blower operates continuously. With fan switch in AUTO position, blower cycles with demand or runs continuously while heating or cooling circuit cycles.
3 – Depending on the type of indoor thermostat, blower and entire unit will be off when the system switch is in OFF position.
B-Temperature Rise (FIGURE 59)
Temperature rise for EL196UHE units depends on unit input, blower speed, blower horsepower and static pressure as marked on the unit rating plate. The blower speed must be set for unit operation within the range of “TEMP. RISE °F” listed on the unit rating plate.
°
TEMPERATURE RISE Supply Duct Temperature ____ Return Duct Temperature ____ Temperature Rise = ____

C-External Static Pressure
1 – Tap locations shown in FIGURE 60.
2 – Punch a 1/4″ diameter hole in supply and return air plenums. Insert manometer hose flush with inside edge of hole or insulation. Seal around the hose with permagum. Connect the zero end of the manometer to the discharge (supply) side of the system. On ducted systems, connect the other end of manometer to the return duct as above.
3 – With only the blower motor running and the evaporator coil dry, observe the manometer reading. Adjust blower motor speed to deliver the air desired according to the job requirements. For heating speed external static pressure drop must not be more than 0.5″ W.C. For cooling speed external static pressure drop must not be more than 0.8″ W.C.
4 – Seal the hole when the check is complete.
EXTERNAL STATIC PRESSURE
Supply Duct Static ____ Return Duct Static + _
Total Duct Static = ____
(dry coil)

SUPPLY AIR

Supply Air

Duct Static

or

FIGURE 59

Temperatures RETURN AIR

Return Air
FIGURE 60
D-Blower Speed Taps
Blower speed tap changes are made on the integrated control. See FIGURE 3 or FIGURE 5. The heating tap is connected to the “HEAT” terminal and the cooling tap is connected to the “COOL” terminal. On all units the continuous blower tap is connected to the “FAN” terminal. Unused taps must be secured on two dummy terminals labeled “PARK. To change out existing speed tap, turn off power and switch out speed tap with tap connected to “PARK”. See blower speed tap table on unit diagram for motor tap colors for each speed.

Page 47

VI-MAINTENANCE
WARNING
ELECTRICAL SHOCK, FIRE, OR EXPLOSION HAZARD. Failure to follow safety warnings exactly could result in dangerous operation, serious injury, death or property damage.
Improper servicing could result in dangerous operation, serious injury, death, or property damage. Before servicing, disconnect all electrical power to the furnace.
At the beginning of each heating season, system should be checked as follows by a qualified service technician: Blower
Check the blower wheel for debris and clean if necessary. The blower motors are prelubricated for extended bearing life. No further lubrication is needed.
WARNING
The blower access panel must be securely in place when the blower and burners are operating. Gas fumes, which could contain carbon monoxide, can be drawn into living space resulting in personal injury or death.
Filters
All air filters are installed external to the unit. Filters should be inspected monthly. Clean or replace the filters when necessary to ensure proper furnace operation. TABLE 22 lists recommended filter sizes.
WARNING
If a highefficiency filter is being installed as part of this system to ensure better indoor air quality, the filter must be properly sized. Highefficiency filters have a higher static pressure drop than standardefficiency glass/foam filters. If the pressure drop is too great, system capacity and performance may be reduced. The pressure drop may also cause the limit to trip more frequently during the winter and the indoor coil to freeze in the summer, resulting in an increase in the number of service calls. Before using any filter with this system, check the specifications provided by the filter manufacturer against the data given in the appropriate Lennox Product Specifications bulletin. Additional information is provided in Service and Application Note ACC002 (August 2000).

TABLE 22

Furnace Cabinet Width

Filter Size

Side Return

Bottom Return

17-1/2″

16 X 25 X 1 (1)

16 X 25 X 1 (1)

21″

16 X 25 X 1 (1)

20 X 25 X 1 (1)

Check the exhaust and air intake pipes and all connections for tightness and to make sure there is no blockage. NOTE – After any heavy snow, ice or frozen fog event the furnace vent pipes may become restricted. Always check the vent system and remove any snow or ice that may be obstructing the plastic intake or exhaust pipes.

Electrical

WARNING
Fire Hazard. Use of aluminum wire with this product may result in a fire, causing property damage, severe injury or death. Use copper wire only with
this product.

WARNING
Failure to use properly sized wiring and circuit
breaker may result in property damage. Size wiring and circuit breaker(s) per Product Specifications bulletin (EHB) and unit rating plate.

1 – Check all wiring for loose connections.
2 – Check for the correct voltage at the furnace (furnace operating). Correct voltage is 120VAC + 10%
3 – Check amp-draw using a true RMS meter on the blower motor with blower access panel in place. See FIGURE 61.
Unit Nameplate__Actual__

Check Motor Amp Draw

EXPOFF MR W 3
21 kWh kVAr
V1 V2 V3 CMOM
True RMS Meter
FIGURE 61

Page 48

Winterizing and Condensate Trap Care
1 – Turn off power to the furnace. 2 – Have a shallow pan ready to empty condensate
water. 3 – Remove the clean out cap from the condensate trap
and empty water. Inspect the trap then reinstall the clean out cap.
Condensate Hose Screens (FIGURE 62)
Check the condensate hose screens for blockage and clean if necessary.
1 – Turn off power to the unit. 2 – Remove hoses from cold end header box. Twist
and pull screens to remove. 3 – Inspect screens and rinse with tap water if needed. 4 – Reinstall screens, reconnect hoses and turn on
power to unit.
Condensate Hose Screens

Hose

Hose

FIGURE 62
Cleaning Heat Exchanger
If cleaning the heat exchanger becomes necessary, follow the below procedures and refer to FIGURE 1 when disassembling unit. Use papers or protective covering in front of furnace while removing heat exchanger assembly.
1 – Turn off electrical and gas supplies to the furnace.
2 – Remove the furnace access panels.
3 – Disconnect the 2 wires from the gas valve.
4 – Remove gas supply line connected to gas valve. Remove the burner box cover (if equipped) and remove gas valve/manifold assembly.
5 – Remove sensor wire from sensor. Disconnect 2-pin plug from the ignitor.
6 – Disconnect wires from flame roll-out switches.
7 – Disconnect combustion air intake pipe. It may be necessary to cut the existing pipe to remove burner box assembly.
8 – Remove four burner box screws at the vestibule panel and remove burner box. Set burner box assembly aside. NOTE – If necessary, clean burners at this time. Follow procedures outlined in Burner Cleaning section.
9 – Loosen the clamps to the flexible exhaust coupling.
10 – Disconnect condensate drain line from the cold end header box.

11 – Disconnect condensate drain tubing from flue collar. Remove screws that secures the flue collar into place. Remove flue collar. It may be necessary to cut the exiting exhaust pipe for removal of the fitting.
12 – Mark and disconnect all combustion air pressure tubing from cold end header collector box.
13 – Mark and remove wires from pressure switch assembly.Remove the assembly. Keep tubing attached to pressure switches.
14 – Disconnect the plug from the combustion air inducer. Remove two screws which secure combustion air inducer to collector box. Remove combustion air inducer assembly. Remove ground wire from vest panel.
15 – Disconnect the condensate drain line.
16 – Remove cold end header box.
17 – Remove electrical junction box from the side of the furnace.
18 – Mark and disconnect any remaining wiring to heating compartment components. Disengage strain relief bushing and pull wiring and bushing through the hole in the blower deck.
19 – Remove the primary limit from the vestibule panel.
20 – Remove two screws from the front cabinet flange at the blower deck. Spread cabinet sides slightly to allow clearance for removal of heat exchanger.
21 – Remove screws along vestibule sides and bottom which secure vestibule panel and heat exchanger assembly to cabinet. Remove two screws from blower rail which secure bottom heat exchanger flange. Remove heat exchanger from furnace cabinet.
22 – Back wash heat exchanger with soapy water solution or steam. If steam is used it must be below 275°F (135°C) .
23 – Thoroughly rinse and drain the heat exchanger. Soap solutions can be corrosive. Take care to rinse entire assembly.
24 – Reinstall heat exchanger into cabinet making sure that the clamshells of the heat exchanger assembly is engaged properly into the support bracket on the blower deck. Remove the indoor blower to view this area through the blower opening.
25 – Re-secure the supporting screws along the vestibule sides and bottom to the cabinet.
26 – Reinstall cabinet screws on front flange at blower deck.
27 – Reinstall the primary limit on the vestibule panel.
28 – Route heating component wiring through hole in blower deck and reinsert strain relief bushing.
29 – Reinstall electrical junction box.
30 – Reinstall the cold end header box.

Page 49

31 – Reinstall the combustion air inducer. Reconnect the plug to the wire harness.
32 – Reinstall pressure switches and reconnect pressure switch wiring.
33 – Carefully connect combustion air pressure switch tubing from pressure switches to proper ports on cold end header collector box.
34 – Reconnect condensate drain line to the cold end header box.
35 – Use securing screws to reinstall flue collar to the top cap on the furnace. Reconnect exhaust piping and exhaust drain tubing.
36 – Replace flexible exhaust adapter on combustion air inducer and flue collar. Secure using two existing hose clamps.
37 – Reinstall burner box assembly in vestibule area. Secure burner box assembly to vestibule panel using four existing screws. Make sure burners line up in center of burner ports
38 – Reconnect flame roll-out switch wires.
39 – Reconnect sensor wire and reconnect 2-pin plug from ignitor.
40 – Reinstall gas valve manifold assembly. Reconnect gas supply line to gas valve.
41 – Reconnect the combustion air intake pipe.
42 – Reinstall burner box cover.
43 – Reconnect wires to gas valve.
44 – Replace the blower compartment access panel.
45 – Reconnect gas supply piping. Turn on power and gas supply to unit.
46 – Follow lighting instructions on unit nameplate to light and operate furnace for 5 minutes to ensure the furnace is operating properly.
47 – Check all piping connections, factory and field, for gas leaks. Use a leak detecting solution or other preferred means.
48 – Replace heating compartment access panel.
CAUTION
Some soaps used for leak detection are corrosive to certain metals. Carefully rinse piping thoroughly after leak test has been completed. Do not use matches, candles, flame or other sources of ignition to check for gas leaks.

Cleaning the Burner Assembly (if needed)
1 – Turn off electrical and gas power supplies to furnace. Remove upper and lower furnace access panels.
2 – Disconnect the wires from the gas valve.
3 – Remove the burner box cover (if equipped).
4 – Disconnect the gas supply line from the gas valve. Remove gas valve/manifold assembly.
5 – Mark and disconnect sensor wire from the sensor. Disconnect wires from flame rollout switches.
6 – Disconnect combustion air intake pipe. It may be necessary to cut the existing pipe to remove burner box assembly.
7 – Remove four screws which secure burner box assembly to vest panel. Remove burner box from the unit.
8 – Use the soft brush attachment on a vacuum cleaner to gently clean the face of the burners. Visually inspect the inside of the burners and crossovers for any blockage caused by foreign matter. Remove any blockage.
9 – Reinstall the burner box assembly using the existing four screws. Make sure that the burners line up in the center of the burner ports.
10 – Reconnect the sensor wire and reconnect the 2-pin plug to the ignitor wiring harness. Reconnect wires to flame rollout switches.
11 – Reinstall the gas valve manifold assembly. Reconnect the gas supply line to the gas valve. Reinstall the burner box cover.
12 – Reconnect wires to gas valve.
13 – Replace the blower compartment access panel.
14 – Refer to instruction on verifying gas and electrical connections when re- establishing supplies.
15 – Follow lighting instructions to light and operate furnace for 5 minutes to ensure that heat exchanger is clean and dry and that furnace is operating properly.
16 – Replace heating compartment access panel.

Page 50

VII-WIRING DIAGRAM AND SEQUENCE OF OPERATION
1 – Line voltage is applied to L1 and N. the T1 low voltage transformer is energized, and line voltage is applied to B3 indoor blower. 2 – S47 rollout switch(es) must be closed in order for 24V from transformer to be output on integrated control “R” to power thermostat. 3 – When there is a call for heat, W1 of the thermostat energizes W of the furnace control with 24VAC. 4 – A92 integrated control runs a self-check. S10 primary limit and S21 secondary limit contacts are found to be closed. Call for heat can continue. 5 – A92 integrated control energizes B6 combustion air inducer. S18 combustion air pressure switch closes . Once S18 closes, a 15-second pre-
purge follows.
6 – A92 integrated control energizes R33 ignitor. A 20-second warm-up period begins. 7 – GV1 gas valve opens for a 4-second trial for ignition 8 – Flame is sensed, gas valve remains open for the heat call. 9 – After 30-second delay (from flame sensed), A92 integrated control applies 24VAC to Heat speed of B3 indoor blower. 10 – When heat demand is satisfied, W1 of the indoor thermostat de-energizes W of A92integrated control which de-energizes GV1 gas valve. 11 – B6 combustion air inducer continues a 5-second post-purge period, and B3 indoor blower completes a selected OFF time delay. 12 –
Page 51

Heating Sequence of Operation

HEATING SEQUENCE OF OPERATION

NORMAL HEATING MODE
POWER ON CONTROL SELF-CHECK OKAY?

ABNORMAL HEATING MODE

GAS VALVE OFF. COMBUSTION AIR INDUCER OFF.

NO

INDOOR BLOWER DELAY OFF.

LED SLOW FLASH

(RESET CONTROL BY TURNING MAIN POWER OFF.)

YES IS POLARITY CORRECT?
YES
IS THERE A PROPER GROUND? YES
NO IS VOLTAGE ABOVE 70 VOLTS?

NO LED FLASHES CODE 1 – POLARITY REVERSED.
NO LED FLASHES CODE 2 – IMPROPER GROUND.
LED FLASHES CODE 13 – LOW LINE VOLTAGE. CONTROL WILL NOT RESPOND TO A CALL FOR HEATING UNTIL VOLTAGE RISES ABOVE 75 VOLTS.

YES ROLLOUT SWITCH CLOSED?
YES

LED FLASHES CODE 8 – ROLLOUT SWITCH OPEN.

NO

GAS VALVE OFF. COMBUSTION AIR INDUCER ON.

INDOOR BLOWER ON.

SEQUENCE HOLDS UNTIL ROLLOUT SWITCH CLOSES

AND POWER IS RESET OR T’STAT IS INTERRUPTED

FOR MINIMUM OF 1 SECOND.

BURNER OFF?

NO

LED FLASHES CODE 12 – FLAME SENSED WITHOUT GAS VALVE ENERGIZED.

(Flame sensed without gas valve energized)

GAS VALVE OFF. COMBUSTION AIR INDUCER ON.

INDOOR BLOWER ON HEATING SPEED.

YES

NO

NORMAL OPERATION:

LED SLOW FLASH

YES
THERMOSTAT CALLS FOR HEAT: LED SLOW FLASH
YES

LED FLASHES CODE 7 – PRIMARY LMIT OPEN. COMBUSTION AIR INDUCER OFF.INDOOR BLOWER ON
NO

PRIMARY LIMIT SWITCH. CLOSED?
YES
IS COMBUSTION AIR PRESSURE SWITCH OPEN?
YES IS COMBUSTION AIR INDUCER
ENERGIZED? YES HAS COMBUSTION AIR PRESSURE SWITCH CLOSED IN 2.5 MINUTES?
YES
CONTINUED NEXT PAGE

LED FLASHES CODE 11 – PRESSURE

SWITCH CLOSED.

NO

GAS VALVE OFF COMBUSTION AIR

INDUCER OFF. INDOOR BLOWER

OFF WITH DELAY.

(Sequence holds until pressure switch

opens or thermostat resets control.)

LED FLASHES CODE 9 – PRESSURE SWITCH FAILED NO TO CLOSE OR OPENED DURING HEAT DEMAND.
PRESSURE SWITCH IS IN WATCHGUARD MODE. GAS VALVE OFF. COMBUSTION AIR INDUCER OFF.
INDOOR BLOWER OFF WITH DELAY. IS 5-MINUTE RESET PERIOD COMPLETE?

YES

Page 52

Heating Sequence of Operation Continued

HEATING SEQUENCE CONTINUED

NORMAL HEATING MODE

ABNORMAL HEATING MODE

15-SECOND COMBUSTION AIR INDUCER PREPURGE INITIATED BY CLOSED PRESSURE SWITCH. YES
IGNITOR WARM-UP — 20 SECONDS. YES
4-SECOND TRIAL FOR IGNITION. GAS VALVE OPENS. IGNITOR ENERGIZED FOR
FIRST 3 SECONDS OF THE TRIAL.
YES
FLAME STABILIZATION PERIOD. 4 SECONDS
FLAME RECTIFICATION CURRENT CHECK. CAN FLAME BE PROVEN WITHIN 4 SECONDS AFTER GAS VALVE OPENS?
(0.5 microamps)
YES
FLAME PRESENT?

NO NO
NO

NO IS VOLTAGE ABOVE 70 VOLTS?
YES

LED FLASHES CODE 13 LOW LINE VOLTAGE.
ONCE VOLTAGE IS ABOVE 75 VOLTS, HEATING
SEQUENCE RESTARTS.

GAS VALVE OFF. COMBUSTION AIR INDUCER ON.

INDOOR BLOWER OFF.

HAS CONTROL FAILED TO SENSE FLAME FOR

NO

FIVE CONSECUTIVE TRIES DURING A SINGLE

HEAT DEMAND?

LED SIGNAL WATCHGUARD FAILURE CODE WATCHGUARD MODE. GAS VALVE OFF. COMBUSTION AIR INDUCER OFF. INDOOR BLOWER OFF WITH DELAY
IS 60-MINUTE RESET PERIOD COMPLETE?
HAS CONTROL RESET IGNITION SEQUENCE FOUR TIMES?

YES

YES

NO YES

YES
FLAME SIGNAL 1.5 MICROAMPS OR GREATER? YES

NO LED FLASHES CODE 4 – LOW FLAME SIGNAL.
(Does not affect operation of control)

LED FLASHES CODE 7 – PRIMARY LIMIT OPEN. GAS VALVE, COMB. AIR INDUCER

INDOOR BLOWER ON AFTER 30-SECOND DELAY
YES PRIMARY LIMIT SWITCH CLOSED?
YES

NAL LIMIT SWITCH

LED FLASHES CODE 7 – PRIMARY LIMIT OPEN GAS VALVE DE-ENERGIZED.
NO COMBUSTION AIR INDUCER DE-ENERGIZED. INDOOR BLOWER ON UNTIL SWITCH CLOSES. LIMIT SWITCH CLOSED?
YES

OPEN UNTIL MAIN POWER IS
INTERRUPTED OR T’STAT IS CYCLED OFF/ON FOR 1 SEC. MINIMUM. 60-MINUTE

HAS PRIMARY LIMIT RESET TIME EXCEEDED 3 MINUTES?

YES RIOD STARTS AT TIME LIMIT CLOSES. IS 60-MIN. PERIOD

COMPLETE?

NO

ROLLOUT SWITCH CLOSED? YES
COMBUSTION AIR PRESSURE SWITCH CLOSED?

NO LED FLASHES CODE 8 – ROLLOT SWITCH OPEN.
GAS VALVE POWER OFF. COMBUSTION AIR INDUCER POWER ON. INDOOR BLOWER ON SEQUENCE HOLDS UNTIL ROLLOUT
SWITCH IS RESET AND MAIN POWER IS INTERRUPTED OR THERMOSTAT IS CYCLED OFF/ON FOR 1 SEC. MINIMUM.
NO

YES
THERMOSTAT DEMAND SATISFIED. YES
LED SLOW FLASH.
YES
COMB. AIR INDUCER CONTINUES 5-SECOND POST PURGE AFTER T’STAT DEMAND IS SATISFIED. INDOOR AIR BLOWER COMPLETES SELECTED “OFF”
DELAY BEFORE SHUTTING OFF.

HAS PRESSURE SWITCH OPENED 5 TIMES IN THE SAME HEAT DEMAND?

LED FLASHES CODE 10

NO

YES 1 HR PRESSURE

SWITCH

GAS VALVE DE-ENERGIZED. COMBUSTION AIR WATCHGUARD

INDUCER ON. INDOOR BLOWER OFF WITH

MODE

DELAY. HAS CAB PRESSURE SWITCH CLOSED

WITHIN 2.5 MINUTES? NO

YES

5-MINUTE PRESSURE SWITCH

WATCHGUARD MODE.

Page 53

Cooling Sequence of Operation

COOLING SEQUENCE OF OPERATION

NORMAL COOLING MODE

ABNORMAL COOLING MODE

POWER ON

IGNITION CONTROL MAIN POWER ON.
CONTROL SELF DIAGNOSTIC CHECK. IS CONTROL OPERATING NORMALLY?
YES
IS THERE A PROPER GROUND? YES
IS POLARITY CORRECT? YES NO IS VOLTAGE
ABOVE 70 VOLTS? YES
ROLLOUT SWITCH MONITORED CONTINUOUSLY. IS ROLLOUT SWITCH CLOSED?
YES

NO NO NO
NO

GAS VALVE OFF. COMBUSTION AIR INDUCER OFF. INDOOR BLOWER OFF WITH NORMAL DELAY. SIGNAL CIRCUIT BOARD FAILURE AT LED.
INTERRUPT MAIN POWER TO RESET CONTROL.
LED FLASHES CODE 2 IMPROPER GROUND CONTROL WILL CONTINUE TO CALL FOR COOLING
IN THIS CONDITION.
LED FLASHES CODE 1 POLARITY REVERSED CONTROL WILL CONTINUE TO CALL FOR COOLING IN
THIS CONDITION.
LED FLASHES CODE 13 LOW VOLTAGE. CONTROL WILL CONTINUE TO CALL FOR COOLING IN THIS CONDITION.
LED FLASHES CODE 8 ROLLOUT SWITCH OPEN. GAS VALVE OFF. COMBUSTION AIR INDUCER ON. INDOOR BLOWER ON. SEQUENCE HOLDS UNTIL ROLLOUT SWITCH
CLOSES AND MAIN POWER IS INTERRUPTED OR THERMOSTAT IS CYCLED OFF/ON FOR 1 SEC. MINIMUM.

LED: SLOW FLASH RATE REMAINS UNCHANGED THROUGHOUT COOLING CYCLE.
THERMOSTAT CALLS FOR COOLING.
COMPRESSOR CONTACTOR AND SYSTEM FAN ENERGIZED WITH 2-SECOND DELAY
(COOLING SPEED). EAC TERM. ENERGIZED.
THERMOSTAT OPENS.
COMPRESSOR OFF.

SYSTEM FAN AND EAC TERM. OFF WITH 45-SECOND DELAY.

Page 54

Continuous Fan / Accessories Sequence of Operation

CONTINUOUS FAN SEQUENCE OF OPERATION
LED: SLOW FLASH RATE REMAINS UNCHANGED THROUGHOUT SEQUENCE.

MANUAL FAN SELECTION MADE AT THERMOSTAT. CONTROL (G) ENERGIZES SYSTEM FAN AT FAN SPEED. EAC TERMINAL IS ENERGIZED.

THERMOSTAT CALLS FOR HEAT (W).

NO

YES

THERMOSTAT CALLS FOR COOLING.

YES

NO

SYSTEM FAN SWITCHED TO COOL SPEED. EAC TERM. REMAINS ON.

SYSTEM FAN CONTINUES FAN SPEED WITHOUT INTERRUPTION. EAC TERMINAL REMAIN ON.
HUM TERMINAL IS ENERGIZED WITH COMBUSTION AIR BLOWER.

THERMOSTAT OPENS.
MANUAL FAN SELECTION MADE AT THERMOSTAT. CONTROL (G) ENERGIZES SYSTEM FAN AT FAN SPEED. EAC TERM. ENERGIZED.

SYSTEM FAN SWITCHES TO HEAT SPEAD AFTER 30 SECOND DELAY. EAC AND HUM TERMINAL REMAIN ON.
THERMOSTAT OPENS.
HUM. TERMINAL OFF AFTER POST PURGE BY COMBUSTION AIR BLOWER. SYTEM FAN SWITCHES TO FAN SPEED AFTER BLOWER
OFF DELAY. EAC CONTINUES WITHOUT INTERRUPTION.

Page 55

Read User Manual Online (PDF format)

Read User Manual Online (PDF format)  >>

Download This Manual (PDF format)

Download this manual  >>

Related Manuals