LENNOX EL196UHE High Efficiency Gas Furnace User Manual
- June 9, 2024
- Lennox
Table of Contents
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