58MSA

4-Way Multipoise Fixed-Capacity
Condensing Gas Furnace

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Service and Maintenance Instructions

For Sizes 040—120, Series 120 and 130

NOTE: Read the entire instruction manual before starting the installation.

This symbol → indicates a change since the last issue.

A93040

SAFETY CONSIDERATIONS

Installing and servicing heating equipment can be hazardous due to gas and electrical components. Only trained and qualified personnel should install, repair, or service heating equipment.

Untrained personnel can perform basic maintenance functions such as cleaning and replacing air filters. All other operations must be performed by trained service personnel. When working on heating equipment, observe precautions in the literature, on tags, and on labels attached to or shipped with the unit and other safety precautions that may apply.

Follow all safety codes. In the United States, follow all safety codes including the National Fuel Gas Code (NFGC) NFPA 54-1999/ANSI Z223.1-1999 and the Installation Standards, Warm Air Heating and Air Conditioning Systems (NFPA 90B)

A98306

Fig. 1—Multipoise Furnace in Upflow Orientation

REGISTERED QUALITY SYSTEM

ANSI/NFPA 90B. In Canada, refer to the CAN/CGA-B/49.1- and .2-M95 National Standard of Canada, Natural Gas and Propane Installation Codes (NSCNGPIC). Wear safety glasses and work gloves. Have a fire extinguisher available during start-up and adjustment procedures and service calls.

Recognize safety information. This is the safety-alert symbol . When you see this symbol on the unit and in instructions or manuals, be alert to the potential for personal injury.

Understand the signal words DANGER, WARNING, and CAUTION. These words are used with the safety-alert symbol. DANGER identifies the most serious hazards which will result in severe personal injury or death. WARNING signifies hazards which could result in personal injury or death. CAUTION is used to identify unsafe practices which would result in minor personal injury or product and property damage. NOTE is used to highlight suggestions which will result in enhanced installation, reliability, or operation.

WARNING

The ability to properly perform maintenance on this equipment requires certain expertise, mechanical skills, tools, and equipment. If you do not possess these, do not attempt to perform any maintenance on this equipment other than those procedures recommended in the User’s Manual. FAILURE TO FOLLOW THIS WARNING COULD RESULT IN POSSIBLE DAMAGE TO THIS EQUIPMENT, SERIOUS PERSONAL INJURY, OR DEATH.
WARNING

Never store anything on, near, or in contact with the furnace, such as:

1. Spray or aerosol cans, rags, brooms, dust mops, vacuum cleaners, or other cleaning tools.
2. Soap powders, bleaches, waxes or other cleaning compounds, plastic or plastic containers, gasoline, kerosene, cigarette lighter fluid, dry cleaning fluids, or other volatile fluids.
3. Paint thinners and other painting compounds, paper bags, or other paper products. Failure to follow this warning can cause corrosion of the heat exchanger, fire, personal injury, or death.

GENERAL

These instructions are written as if the furnace is installed in an upflow application. An upflow furnace application is where the blower is located below the combustion and controls section of the furnace, and conditioned air is discharged upward. Since this furnace can be installed in any of the 4 positions shown in Fig. 2, you may need to revise your orientation to component location accordingly.

1. AIRFLOW
2. UPFLOW
3. HORIZONTAL RIGHT
4. DOWNFLOW
5. HORIZONTAL LEFT

A93041

Fig. 2—Multipoise Orientation

ELECTROSTATIC DISCHARGE (ESD) PRECAUTIONS

CAUTION

Electrostatic discharge can affect electronic components. Take precautions during furnace installation and servicing to protect the furnace electronic control. Precautions will prevent electrostatic discharges from personnel and hand tools which are held during the procedure. These precautions will help to avoid exposing the control to electrostatic discharge by putting the furnace, the control, and the person at the same electrostatic potential.

1. Disconnect all power to the furnace. DO NOT TOUCH THE CONTROL OR ANY WIRE CONNECTED TO THE CONTROL PRIOR TO DISCHARGING YOUR BODY’S ELECTROSTATIC CHARGE TO GROUND.
2. Firmly touch a clean, unpainted, metal surface of the furnace chassis which is close to the control. Tools held in a person’s hand during grounding will be satisfactorily discharged.
3. After touching the chassis you may proceed to service the control or connecting wires as long as you do nothing that recharges your body with static electricity (for example; DO NOT move or shuffle your feet, DO NOT touch ungrounded objects, etc.).
4. If you touch ungrounded objects (recharge your body with static electricity), firmly touch furnace again before touching control or wires.
5. Use this procedure for installed and uninstalled (ungrounded) furnaces.
6. Before removing a new control from its container, discharge your body’s electrostatic charge to ground to protect the control from damage. If the control is to be installed in a furnace, follow items 1 through 5 before bringing the control or yourself into contact with the furnace. Put all used AND new controls into containers before touching ungrounded objects.
7. An ESD service kit (available from commercial sources) may also be used to prevent ESD damage.

CARE AND MAINTENANCE

For continuing high performance and to minimize possible equipment failure, it is essential that maintenance be performed annually on this equipment. Consult your local dealer for maintenance and maintenance contract availability.

WARNING

Turn off the gas and electrical supplies to the unit before performing any maintenance or service. Follow the operating instructions on the label attached to the furnace. Failure to follow this warning could result in personal injury or death.

The minimum maintenance that should be performed on this equipment is as follows:

1. Check and clean or replace air filter each month as required.

2. Check blower motor and wheel for cleanliness annually.

3. Check electrical connections for tightness and controls for proper operation each heating season. Service as necessary.

4. Check for proper condensate drainage. Clean as necessary.

5. Check for blockages in combustion-air and vent pipes annually.

6. Check burners for cleanliness annually.

7. WASHABLE FILTER

8. FILTER RETAINER

9. FILTER SUPPORT

A93046

Fig. 3—Bottom Filter Arrangement

CAUTION

Personal injury could result from sharp metal edges, etc. Use care when removing parts.

Step 1—Cleaning and/or Replacing Air Filter

The air filter arrangement may vary depending on the application or orientation.

CAUTION

Never operate unit without a filter or with the blower access panel removed. Failure to follow this warning could result in a fire or personal injury.

To clean or replace filters, proceed as follows:

1. Turn off electrical supply to furnace.
2. Remove main furnace door and blower access panel.
3. Release filter retainer wire. (See Figs. 3 and 4.)
4. Slide filter out of furnace.
5. Furnaces are equipped with permanent, washable filter(s). Clean filter by spraying cold tap water through filter in opposite direction of airflow.
6. Rinse filter and let dry. Oiling or coating filter is not recommended.
7. Place filter in furnace.
8. Replace blower access panel and main furnace door.
9. Turn on electrical supply to furnace.

NOTE: If the filter has cross-mesh binding, the binding must face the blower. If the filter has an air direction arrow, the arrow must point toward the blower.

Step 2—Blower Motor and Wheel Maintenance

To ensure long life, economy, and high efficiency, clean accumulated dirt and grease from blower wheel and motor annually.

The inducer and blower motors are pre-lubricated and require no additional lubrication. These motors can be identified by the absence of oil ports on each end of the motor.

The following items should be performed by a qualified service technician.

Clean blower motor and wheel as follows:

1. Turn off electrical supply to furnace.
2. Remove main furnace door and blower access panel.

1. WASHABLE FILTER
2. FILTER RETAINER

A93045

Fig. 4—Filter Installed for Side Inlet

3. Disconnect wires.
All factory wires can be left connected, but field thermostat connections may need to be disconnected depending on their length and routing.
4. Position control box, transformer, and door switch assembly to right side of furnace casing.
5. If condensate trap is located in left- or right-hand side of furnace casing, proceed to item 6, otherwise remove trap and tubing as described below:

a. Disconnect field drain connection from condensate trap.
b. Disconnect drain and relief port tubes from condensate trap.
c. Remove condensate trap from blower shelf.

6. Remove screws securing blower assembly to blower shelf and slide blower assembly out of furnace.
7. Clean blower wheel and motor by using a vacuum with soft brush attachment. Be careful not to disturb balance weights (clips) on blower wheel vanes. Do not bend wheel or blades as balance will be affected.
8. If greasy residue is present on blower wheel, remove wheel from the blower housing and wash it with an appropriate degreaser. To remove wheel:

a. Mark blower wheel location on shaft before disassembly to ensure proper reassembly.
b. Loosen setscrew holding blower wheel on motor shaft.

NOTE: Mark blower mounting arms and blower housing so each arm is positioned at the same hole location during reassembly.

c. Mark blower wheel orientation and cutoff plate location to ensure proper reassembly.
d. Remove screws securing cutoff plate and remove cutoff plate from housing.
e. Remove bolts holding motor mounts to blower housing and slide motor and mounts out of housing. Disconnect capacitor and ground wire attached to blower housing before removing motor.
f. Remove blower wheel from housing.
g. Clean wheel per instructions on degreaser cleaner.

9. Reassemble motor and blower wheel by reversing items 8b through 8f. Ensure wheel is positioned for proper rotation. Be sure to attach ground wire.
10. Reinstall blower assembly in furnace.
11. Reinstall condensate trap and tubing if previously removed.

a. Reinstall condensate trap in hole in blower shelf.
b. Connect condensate trap drain tubes. See Fig. 8 or tubing diagram on main furnace door for proper tube location.

(1.) Connect 1 tube (blue or blue and white striped) from collector box.
(2.) Connect 1 tube (violet or unmarked) from inducer housing.
(3.) Connect 1 tube (relief port, green or pink) from collector box.

c. Connect field drain to condensate trap.

NOTE: Ensure tubes are not kinked or pinched, as this will affect operation.

12. Reinstall control box, transformer, and door switch assembly on blower shelf.
13. Reconnect wires.
Refer to furnace wiring diagram and connect thermostat leads if previously disconnected. (See Fig. 15.)

NOTE: Refer to Table 1 for motor speed lead relocation if leads were not identified before disconnection.

COLOR

| SPEED| FACTORY ATTACHED TO
---|---|---
Black| High|

Cool

Yellow (When Present)

| Medium High| Spare
Blue| Medium Low|

Heat

Red

| Low| Spare
White| Common|

Com

CAUTION

Heating speed selection MUST be adjusted to provide proper temperature rise as specified on the rating table. Failure to adjust the heating speed may shorten heat exchanger life.

14. Turn on electrical supply. Manually close blower access panel door switch. Use a piece of tape to hold switch closed. Check for proper rotation and speed changes between heating and cooling by jumpering R to G and R to Y on control center thermostat terminals. (See Fig. 11.)

WARNING

Blower access panel door switch opens 115-v power to control center. No component operation can occur. Caution must be taken when manually closing this switch for service purposes. Failure to follow this warning could result in personal injury or death.

15. If furnace is operating properly, release blower access panel door switch, replace blower access panel, and replace main furnace door.

Step 3—Cleaning Burners

The following items should be performed by a qualified service technician. If the burners develop an accumulation of light dirt or dust, they may be cleaned by using the following procedure:

1. Turn off gas and electrical supplies to furnace.
2. Remove main furnace door.
3. Remove burner box cover.
4. Using backup wrench, disconnect gas supply pipe from gas valve.
5. Remove wires from gas valve. Note location for reassembly.

CAUTION

Label all wires prior to disconnection when servicing controls. Wiring errors can cause improper and dangerous operation.

6. Remove burner box pressure tube from gas valve regulator fitting.
7. Remove screws that secure manifold to burner box. (See Fig. 5.)

1. MANIFOLD MOUNTING SCREW
2. MANIFOLD
3. GAS VALVE REGULATOR FITTING
4. GAS VALVE

A93295

Fig. 5—Burner Box Assembly

8. Remove manifold, orifices, and gas valve as 1 assembly.
9. Remove screws attaching burner assembly in burner box.
10. Remove burner assembly from burner box.

NOTE: All burners are attached to burner bracket and can be removed as 1 assembly.

11. Clean burners with soft brush and vacuum.
12. Reinstall manifold, orifice, and gas valve assembly in burner box. Ensure manifold seal grommet is installed properly and burners fit over orifices.
13. Reconnect wires to gas valve. Refer to furnace wiring diagram for proper wire location.
14. Reinstall burner box pressure tube to gas valve regulator fitting.
15. Reinstall gas supply pipe to gas valve using backup wrench on gas valve to prevent rotation and improper orientation.

NOTE: Use propane gas resistant pipe dope to prevent gas leaks. DO NOT use Teflon tape.

WARNING

Gas valve switch or knob MUST be facing forward or tilted upward. Failure to follow this warning could result in property damage, personal injury, or death.

16. Replace burner box cover.
17. Turn on gas and electrical supplies to furnace.
18. Check for gas leaks.

WARNING

Never use matches, candles, flame, or other sources of ignition to check for gas leakage. Use a soap-and-water solution. Failure to follow this warning could result in a fire, personal injury, or death.

19. Replace main furnace door.

Step 4—Cleaning Heat Exchangers

The following items should be performed by a qualified service technician.

PRIMARY HEAT EXCHANGERS

If the heat exchangers get an accumulation of light dirt or dust on the inside, they may be cleaned by the following procedure:

NOTE: If the heat exchangers get a heavy accumulation of soot and carbon, both the primary and secondary heat exchangers should be replaced rather than trying to clean them thoroughly due to their intricate design. A build-up of soot and carbon indicates that a problem exists which needs to be corrected, such as improper adjustment of manifold pressure, insufficient or poor quality combustion air, improper vent termination, incorrect size or damaged manifold orifice(s), improper gas, or a restricted heat exchanger (primary or secondary). Action must be taken to correct the problem.

1. Turn off gas and electrical supplies to furnace.
2. Remove main furnace door.
3. Disconnect wires or connectors to rollout switch, gas valve, ignitor, and flame sensor.

CAUTION

Label all wires prior to disconnection when servicing controls. Wiring errors can cause improper and dangerous operation.

4. Disconnect combustion-air intake pipe from intake housing.
5. Remove the pressure switch tube from intake housing.
6. Remove screws attaching intake housing to burner box, and rotate intake housing away from burner box for removal.
7. Using backup wrench, disconnect gas supply pipe from gas valve.
8. Disconnect pressure tubing from gas valve.
9. Remove 2 screws attaching top filler panel and rotate upwards to gain access to screws attaching burner box to cell panel.
10. Remove screws attaching burner box to cell panel. (See Fig. 5.)

NOTE: Burner box cover, manifold, gas valve, and burner assembly should be removed as 1 assembly.

11. Clean heat exchanger openings with a vacuum and a soft brush. (See Fig. 6.)

NOTE: After cleaning, inspect the heat exchangers to ensure they are free of all foreign objects that may restrict flow of combustion products.

12. Reverse items 4 through 10 for reassembly.

WARNING

The ground wire from the gas valve MUST be attached to the burner box attachment screw. Failure to attach this ground wire to an adequate casing ground will cause the furnace control to lock out.

NOTE: Be sure burner box gasket is installed between burner box and cell panel. If gasket is damaged, replace it.

1. PRIMARY HX INLET OPENINGS

A93080

Fig. 6—Cleaning Inlet Openings of Primary Heat Exchangers

NOTE: Inspect combustion-air intake housing. If foamed gasket was removed, check for any damage. If gasket is damaged in any way, it must be repaired. To repair, remove damaged gasket section, apply sealant releasing agent such as PAM cooking spray or equivalent (must not contain corn or canola oil, aromatic or halogenated hydrocarbons or inadequate seal may occur) to burner box and apply a small bead of G.E. RTV 162, G.E. RTV 6702, or Dow- Corning RTV 738 sealant to edge of combustion-air intake housing. (See Fig. 7.)

1. RTV
2. PAM

A93087

Fig. 7—Combustion-Air Intake Housing Gasket Repair

13. Refer to furnace wiring diagram and reconnect wires to rollout switch, gas valve, ignitor, and flame sensor.
14. Reconnect pressure switch tubes to gas valve and intake housing. Refer to tube routing label on main furnace door for proper tube location. Be sure tubes are not kinked. (See Fig. 8.)
15. Turn on gas and electrical supplies to furnace.
16. Check furnace operation through 2 complete heat operating cycles. Look through sight glass in burner enclosure to check burners. Burner flames should be clear blue, almost transparent. (See Fig. 9.)
17. Check for gas leaks.

TUBE ROUTING

Furnace is shipped from factory in upflow configuration. Pressure tube and drain tube routing MUST match the diagrams below.

Condensate Trap; Factory Installed in Blower Shelf| Tube location when used in UPFLOW application|

Condensate Trap on LEFT Side Optional

(Blower access panel removed)

1. BURNER ENCLOSURE PRESSURE REFERENCE TUBE ASSEMBLY

2. CAP

3. PLUG

4. COLLECTOR BOX DRAIN TUBE (BLUE & WHITE STRIPED)

5. CONDENSATE TRAP

6. FIELD-INSTALLED FACTORY-SUPPLIED DRAIN TUBE COUPLING
   (RIGHT DRAIN OPTION)

7. FIELD-INSTALLED FACTORY-SUPPLIED 1/2-IN. CPVC STREET ELBOWS (2) FOR LEFT DRAIN OPTION

8. FIELD-INSTALLED FACTORY-SUPPLIED DRAIN TUBE

9. FIELD-INSTALLED FACTORY-SUPPLIED DRAIN TUBE COUPLING (LEFT DRAIN OPTION)

10. COLLECTOR BOX DRAIN TUBE (BLUE)

11. INDUCER HOUSING (MOLDED) DRAIN TUBE
    (BEHIND COLLECTOR BOX DRAIN TUBE)

12. COLLECTOR BOX TUBE (GREEN)

13. COLLECTOR BOX TUBE (PINK)

|

1. BURNER ENCLOSURE PRESSURE REFERENCE TUBE ASSEMBLY
2. CAP
3. PLUG
4. COLLECTOR BOX DRAIN TUBE (BLUE & WHITE STRIPED)
5. INDUCER HOUSING DRAIN TUBE (VIOLET)
6. CONDENSATE TRAP
7. COLLECTOR BOX DRAIN TUBE (BLUE)
8. COLLECTOR BOX TUBE (GREEN)
9. COLLECTOR BOX TUBE (PINK)

Condensate Trap on LEFT Side

| Tube location when used in DOWNFLOW application|

Condensate Trap on RIGHT Side

1. COLLECTOR BOX DRAIN TUBE (BLUE) PLUGGED END
2. PLUG
3. COLLECTOR BOX EXTENSION TUBE
4. COLLECTOR BOX TUBE (PINK)
5. INDUCER HOUSING DRAIN TUBE (VIOLET)
6. BURNER ENCLOSURE PRESSURE REFERENCE TUBE ASSEMBLY
7. CONDENSATE TRAP
8. COLLECTOR BOX DRAIN TUBE (BLUE & WHITE STRIPED
9. COLLECTOR BOX TUBE (GREEN)
10. CAP

|

1. PLUG
2. CAP
3. COLLECTOR BOX DRAIN TUBE (BLUE)
4. COLLECTOR BOX TUBE (PINK)
5. COLLECTOR BOX TUBE (GREEN)
6. COLLECTOR BOX EXTENSION TUBE
7. BURNER ENCLOSURE PRESSURE REFERENCE TUBE ASSEMBLY
8. CONDENSATE TRAP
9. COLLECTOR BOX EXTENSION DRAIN TUBE
10. GAS VALVE
11. DRAIN TUBES ROUTED IN FRONT OF GAS VALVE
12. DRAIN TUBE COUPLING
13. INDUCER HOUSING DRAIN TUBE (VIOLET)
14. COLLECTOR BOX DRAIN TUBE (BLUE & WHITE STRIPED)

Tube location when used on HORIZONTAL – LEFT application

1. COLLECTOR BOX DRAIN TUBE (BLUE & WHITE STRIPED)
2. COLLECTOR BOX TUBE (GREEN)
3. INDUCER HOUSING DRAIN TUBE (VIOLET)
4. COLLECTOR BOX DRAIN TUBE (BLUE)
5. COLLECTOR BOX TUBE (PINK) RELOCATE TUBE BETWEEN BLOWER SHELF AND INDUCER HOUSING FOR 040,060, AND 080 HEATING INPUT FURNACES
6. DRAIN TUBE COUPLING
7. COLLECTOR BOX EXTENSION DRAIN TUBE
8. CONDENSATE TRAP
9. COLLECTOR BOX EXTENSION TUBE
10. BURNER ENCLOSURE PRESSURE REFERENCE TUBE ASSEMBLY
11. CAP
12. PLUG

|

Tube location when used on HORIZONTAL – RIGHT application

1. COLLECTOR BOX DRAIN TUBE (BLUE)
2. COLLECTOR BOX EXTENSION TUBE
3. COLLECTOR BOX TUBE (PINK)
4. AUXILIARY “J” BOX RELOCATED HERE
5. BURNER ENCLOSURE PRESSURE REFERENCE TUBE ASSEMBLY
6. COLLECTOR BOX EXTENSION TUBE
7. CONDENSATE TRAP
8. INDUCER HOUSING DRAIN TUBE (VIOLET)
9. COLLECTOR BOX DRAIN TUBE (BLUE AND WHITE STRIPED)
10. COLLECTOR BOX TUBE (GREEN)
11. CAP
12. PLUG

NOTE:

1. All tubing must be connected securely and routed to avoid kinks and traps.
2. Pressure tubing must always slope away from pressure switch to collector box connection as shown.
3. HORIZONTAL-LEFT installations require the collector box pressure tube to be relocated between the inducer housing and the blower shelf to prevent a trap. Refer to the Installation Instructions for further details.

324999-201 REV. C

A00308

Fig. 8—Furnace Pressure and Drain Tubing Diagram

1. BURNER FLAME
2. BURNER
3. MANIFOLD

A89020

Fig. 9—Burner Flame

WARNING

Never use matches, candles, flame, or other sources of ignition to check for gas leakage. Use a soap-and-water solution. Failure to follow this warning could result in a fire, personal injury, or death.

18. Replace main furnace door.

NOTE: The condensing side (inside) of the secondary heat exchangers CANNOT be serviced or inspected. A small number of bottom outlet openings can be inspected by removing the inducer assembly. See Flushing Collector Box and Drainage System section for details on removing inducer assembly.

Step 5—Flushing Collector Box and Drainage System

1. Turn off gas and electrical supplies to furnace.
2. Remove main furnace door.
3. Disconnect inducer motor and pressure switch wires or connectors.
4. Disconnect pressure switch tubes.
5. Disconnect vent pipe from inducer housing outlet by loosening coupling clamp on inducer outlet.
6. Disconnect drain tube from inducer housing. (See Fig. 8.)
7. Remove inducer housing assembly by removing 4 bolts attaching assembly to cell panel.
8. Flush inside of collector box with water until discharge from condensate trap is clean and runs freely.

NOTE: Ensure the drain tube disconnected from the inducer housing is higher than the collector box opening or water will flow out tube.

9. Inspect inside area of collector box for any pieces of foreign materials and remove if present.

CAUTION

DO NOT use wire brush or other sharp object to inspect or dislodge materials in secondary heat exchangers as failure of the secondary heat exchanger will occur. Flush with water only.

10. Reassemble inducer assembly by reversing items 5-7. Tighten the vent coupling clamp screw(s) to 15 in.-lb of torque.

NOTE: If seal between the inducer housing and the collector box is damaged in any way, it must be repaired. To repair, apply sealant releasing agent such as PAM cooking spray or equivalent (must not contain corn or canola oil, aromatic or halogenated hydrocarbons or inadequate seal may occur) to inducer housing. (See Fig. 10.) Apply a small bead of G.E. RTV 162, G.E. RTV 6702, or Dow-Corning RTV 738 sealant to groove in collector box.

1. RTV
2. PAM

A93081

Fig. 10—Gasket on Collector Box

11. Refer to furnace wiring diagram and connect wires to inducer motor and pressure switch or connectors.
12. Reconnect pressure tubes to pressure switch. See diagram on main furnace door for proper location of tubes. Be sure tubes are not kinked. (See Fig. 8.)
13. Turn on gas and electrical supplies to furnace.
14. Check furnace operation through 2 complete heat operating cycles. Check area below inducer housing, vent pipe, and condensate trap to ensure no condensate leaks occur. If leaks are found, correct the problem.
15. Check for gas leaks.

WARNING

Never use matches, candles, flame, or other sources of ignition to check for gas leakage. Use a soap-and-water solution. Failure to follow this warning could result in a fire, personal injury, or death.

16. Replace main furnace door.

Step 6—Servicing Hot Surface Ignitor

The ignitor does NOT require annual inspection. Check ignitor resistance before removal.

1. Turn off gas and electrical supplies to furnace.
2. Remove main furnace door.
3. Disconnect ignitor wire connection.
4. Check ignitor resistance.

a. Using an ohm meter, check resistance across both ignitor leads in connector.
b. Cold reading should be between 45 ohms and 90 ohms.
c. If ohm reading is higher than 110 ohms, ignitor is cracked and must be replaced.

5. Remove ignitor assembly.

CAUTION

Allow ignitor to cool before removal. Normal operation temperatures exceed 2000°F.

a. Do not remove ignitor from bracket while assembly is in furnace. Using a 1/4 in. nutdriver, remove screw securing bracket and ignitor assembly to bottom of burner box. The screw in the bracket is always located toward outside of burner box. The screw may be hidden by inlet box or inlet pipe, but can be removed without removing either. After removing screw, slide ignitor and bracket toward outside of burner box and pull straight out.

CAUTION

The ignitor is fragile. DO NOT allow it to hit the side of the burner box opening while removing or replacing it.

b. Inspect ignitor for a white area indicating a crack may be present. If found, replace ignitor.

NOTE: A small crack cannot be seen on a new ignitor. After a period of operation, a white area will be visible around the crack.

c. If replacement is required, replace ignitor on ignitor bracket external to furnace to avoid damage as the silicon portion is very brittle and will easily crack or shatter.
d. To remove ignitor from ignitor bracket, remove screw holding ignitor ceramic block to bracket and pull ceramic block out of bracket.

6. To replace ignitor/ignitor assembly, reverse items 5a through 5d.
7. Reconnect ignitor wire connection.
8. Turn on gas and electrical supplies to furnace.
9. Verify ignitor operation by initiating control board self-test feature or by cycling thermostat.
10. Replace main furnace door.

Step 7—Electrical Controls and Wiring

CAUTION

There may be more than 1 electrical supply to the unit. Check accessories and cooling unit for additional electrical supplies.

The electrical ground and polarity for 115-v wiring must be maintained properly. Refer to Fig. 11 for field wiring information and to Fig. 15 for unit wiring information.

NOTE: If the polarity is not correct, the STATUS LED on the control center will flash rapidly and prevent the furnace from operating. The control system also requires an earth ground for proper operation of the control center and flame sensing.

The 24-v circuit contains an automotive-type, 3-amp fuse located on the control center. (See Fig. 12.) Any direct shorts of the 24-v wiring during installation, service, or maintenance will cause this fuse to blow. If fuse replacement is required, use ONLY a fuse of identical size.

With power to the unit disconnected, check all electrical connections for tightness. Tighten all screws on electrical connections. If any smoky or burned connections are found, disassemble the connection, clean all parts, strip wire, and reassemble properly and securely.

Reconnect electrical supply to unit and observe unit through 1 complete operating cycle. Electrical controls are difficult to check without proper instrumentation; if there are any discrepancies in the operating cycle, contact your dealer and request service.

Step 8—Checking Heat Tape Operation
(If Applicable)

In applications where the ambient temperature around the furnace is 32°F or lower, freeze protection measures are required. If this application is where heat tape has been applied, check to ensure it will operate when low temperatures are present.

NOTE: Heat tape, when used, should be wrapped around the condensate drain trap and drain line. There is no need to use heat tape within the furnace casing. Most heat tapes are temperature activated, and it is not practical to verify the actual heating of the tape. Check the following:

CAUTION

If this furnace is installed in an unconditioned space where the ambient temperatures may be 32°F or lower, freeze protection measures must be taken.

1. Check for signs of physical damage to heat tape such as nicks, cuts, abrasions, gnawing by animals, etc.
2. Check for discolored heat tape insulation. If any damage or discolored insulation is evident, replace heat tape.
3. Check that heat tape power supply circuit is on.

FIELD 24-V WIRING
FIELD 115-, 208/230-, 460-V WIRING
FACTORY 24-V WIRING
FACTORY 115-V WIRING

1. THREE-WIRE HEATING-ONLY
2. FIVE WIRE
3. NOTE 2
4. THERMOSTAT TERMINALS
5. FIELD-SUPPLIED DISCONNECT
6. 208/230- OR 460-V THREE PHASE
7. 208/230-V SINGLE PHASE
8. CONDENSING UNIT
9. TWO WIRE
10. NOTE 1
11. FURNACE
12. 24-V TERMINAL BLOCK
13. CONTROL BOX
14. AUXILIARY J-BOX
15. 115-V FIELD-SUPPLIED DISCONNECT

NOTES:

1. Connect Y-terminal as shown for proper operation.
2. Some thermostats require a “C” terminal connection as shown.
3. If any of the original wire, as supplied, must be replaced, use same type or equivalent wire.

A98209

Fig. 11—Field Wiring

1. TEST/TWIN
2. 24-V THERMOSTAT TERMINALS
3. HUMIDIFIER TERMINAL (24-VAC 0.5 AMP MAX)
4. LED OPERATION & DIAGNOSTIC LIGHT
5. HARNESS CONNECTOR
6. 24-V TRANSFORMER SEC-2
7. SPARE-1
8. BLOWER SPEED SELECTION TERMINALS
9. SPARE-2
10. EAC-1
11. EAC-ELECTRONIC AIR CLEANER TERMINALS (115-VAC 1.5 AMP MAX)
12. EAC-2
13. 115-VAC (L2) NEUTRAL CONNECTION
14. INDUCER MOTOR CONNECTOR
15. HOT SURFACE IGNITOR CONNECTOR
16. 115-VAC (L1) POWER SUPPLY
17. HEAT
18. COOL
19. 3-AMP FUSE
20. SEC-1

A95086

Fig. 12— Control Center

Step 9—Winterizing

CAUTION

Freezing condensate left in the furnace will damage the equipment.

1. 32°F MINIMUM INSTALLED AMBIENT OR FREEZE PROTECTION REQUIRED

A93058

If the furnace will be off for an extended period of time in a structure where the temperature will drop to 32°F or below, winterize as follows:

1. Turn off electrical supply to furnace.
2. Remove main furnace door.
3. Disconnect drain tube from inducer housing. (See Fig. 13.)
4. Insert funnel in drain tube and pour antifreeze, propylene glycol (RV, swimming pool antifreeze, or equivalent) into furnace until it is visible at point where condensate enters open drain. (See Fig. 14.)
5. Reconnect drain tube to inducer housing.
6. Replace main furnace door.

CAUTION

Do not use ethylene glycol (Prestone II antifreeze/coolant or equivalent automotive type). Failure of plastic components will occur.

WIRING DIAGRAM

See Fig. 15 for Wiring Diagram.

TROUBLESHOOTING

For an explanation of fault codes, refer to service label located on back of main furnace door or Fig. 16, and the Troubleshooting Guide.

The control center stores 1 status code (representing the last fault to occur) for a period of 48 hrs or until the 115- or 24-v power is interrupted.

NOTE: Removing blower access panel will open blower access panel door switch and terminates 115-v power to control center. The status code will be erased. Look into blower access panel sight glass for current LED status BEFORE removing blower access panel.

The unit’s component test is a useful troubleshooting tool since it displays the current status code of the furnace and functionally operates all furnace components except the gas valve. The component test and methods to initiate it are described below.

A99118

Fig. 13—Inducer Housing Drain Tube

COMPONENT TEST SEQUENCE

NOTE: All components are functionally operated except the gas valve.

When the component test is initiated, the following sequence of events occurs:

1. LED flashes a status code 4 times.
2. Inducer motor starts and continues to run for remainder of component test.
3. Hot surface ignitor is energized for 15 sec, then de-energized.
4. Main blower operates at cooling speed for 10 sec, then turns off.
5. Main blower operates at heating speed for 10 sec, then turns off.
6. Inducer motor stops.

Component test can be initiated by one of the following procedures.

INITIATING COMPONENT TEST AND RETRIEVING STATUS CODE BY REMOVING MAIN LIMIT SWITCH WIRE

NOTE: NO thermostat signal may be present at control center and all blower time delay of periods must be completed.

1. Leave 115-v power to furnace turned on.
2. Remove main furnace door.
3. Look into blower access panel sight glass for current LED status.

NOTE: Leave blower access panel installed to maintain power to control center to view current LED status.

4. BRIEFLY remove either wire from the main limit switch until the LED goes out, then reconnect it.

A99119

Fig. 14—Funnel in Drain and Antifreeze Running Through Trap

CAUTION

Make sure the limit switch wire does not contact any metallic component such as the gas valve. If wire is shorted, 3-amp fuse on control center will blow.

NOTE: If wire to main limit is disconnected longer than 4 sec, the control senses limit circuit is open. Main blower will start and retrieval request will be ignored.

5. When above items have been completed, the component test sequence will occur as described in the Component Test Sequence section above.

NOTE: Be sure to record the status code which is flashed 4 times at start of component test for further troubleshooting.

6. After component test is completed and LED is ON continuously indicating the furnace is ready to operate when a signal from the thermostat is received, replace main furnace door.

INITIATING COMPONENT TEST AND RETRIEVING STATUS CODE BY JUMPERING CONTROL TEST TERMINAL

1. Remove main furnace door.
2. Remove blower access panel.
3. Manually close blower access panel door switch. Use a piece of tape to hold switch closed.

↓

|

SCHEMATIC DIAGRAM
(NATURAL GAS & PROPANE)

TO 115VAC FIELD DISCONNECT

NOTES:

1. IF ANY OF THE ORIGINAL EQUIPMENT WIRE IS REPLACED USE WIRE RATED FOR 105∞C. 
2. INDUCER (IDM) AND BLOWER (BLWM) MOTORS CONTAIN INTERNAL AUTO-RESET THERMAL OVERLOAD SWITCHES (OL). 
3. BLOWER MOTOR SPEED SELECTIONS ARE FOR AVERAGE CONDITIONS, SEE INSTALLATION INSTRUCTIONS FOR DETAILS ON OPTIMUM SPEED SELECTION. 
4. USE ONLY COPPER WIRE BETWEEN THE DISCONNECT SWITCH AND THE FURNACE JUNCTION BOX (JB). 
5. THIS WIRE MUST BE CONNECTED TO FURNACE SHEETMETAL FOR CONTROL TO PROVE FLAME. 
6. FACTORY CONNECTED WHEN LGPS NOT USED. 
7. REPLACE ONLY WITH A 3 AMP FUSE. 
8. YELLOW LEAD NOT ON ALL MOTORS. 
9. BLOWER-ON DELAY, GAS HEATING 60 SECONDS, COOLING OR HEAT PUMP 2 SECONDS. 
10. BLOWER-OFF DELAY, GAS HEATING 90, 135, 180 OR 225 SECONDS, COOLING OR HEAT PUMP 90 SECONDS. (135 SECONDS ONLY ON SOME MODELS) 
11. IGNITION-LOCKOUT WILL OCCUR AFTER FOUR CONSECUTIVE UNSUCCESSFUL TRIALS-FOR-IGNITION. CONTROL WILL AUTO-RESET AFTER THREE HOURS. 
12. SOME MODELS MAY HAVE SPAD E QUICK CONNECT TERMINALS. 
13. GAS VALVE LEADS ARE INTERCHANGEABLE ON SINGLE STAGE VALVES.

322854-101 REV. G

---|---
LEGEND

BLWR      BLOWER MOTOR RELAY, SPST-(N.O.)
BLWM     BLOWER MOTOR
CAP         CAPACITOR
CPU         MICROPROCESSOR AND CIRCUITRY
EAC-1      ELECTRONIC AIR CLEANER CONNECTION (115 VAC 1.5 AMP MAX.)
EAC-2      ELECTRONIC AIR CLEANER CONNECTION (COMMON)
FRS           FLAME ROLLOUT SW. -MANUAL RESET, SPST-(N.C.)
FSE           FLAME PROVING ELECTRODE
FU1           FUSE, 3 AMP, AUTOMOTIVE BLADE TYPE, FACTORY INSTALLED
FU2           FUSE OR CIRCUIT BREAKER CURRENT INTERRUPT DEVICE (FIELD INSTALLED & SUPPLIED)
GND         EQUIPMENT GROUND
GV            GAS VALVE-REDUNDANT OPERATORS
GVR         GAS VALVE RELAY, DPST-(N.O.)
HI/LO      BLOWER MOTOR SPEED CHANGE RELAY, SPDT
HSI            HOT SURFACE IGNITOR (115 VAC)
HSIR          HOT SURFACE IGNITOR RELAY, SPST-(N.O.)
HUM         24VAC HUMIDIFIER CONNECTION (.5 AMP. MAX.)
IDM          INDUCED DRAFT MOTOR
IDR           INDUCED DRAFT RELAY, SPST-(N.O.)
ILK           BLOWER ACCESS PANEL INTERLOCK SWITCH, SPST-(N.O.)
JB               JUNCTION BOX
LED          LIGHT-EMITTING DIODE FOR STATUS CODES
LGPS         LOW GAS PRESSURE SWITCH, SPST-(N.O.)
LS               LIMIT SWITCH, AUTO RESET, SPST(N.C.)
OL            AUTO-RESET INTERNAL MOTOR OVERLOAD TEMP. SW.
PCB          PRINTED CIRCUIT BOARD
PL1           9-CIRCUIT CONNECTOR
PL2           2-CIRCUIT PCB CONNECTOR
PL3          3-CIRCUIT IDM CONNECTOR
PL4           3-CIRCUIT IDMEXTENSION CONNECTOR
PL5           2-CIRCUIT HSI/PCB CONNECTOR
PRS           PRESSURE SWITCH, SPST-(N.O.)
SW1 & 2    BLOWER OFF DELAY
TEST/TWIN      COMPONENT TEST & TWIN TERMINAL
TRAN       TRANSFORMER-115VAC/24VAC
       JUNCTION
             UNMARKED TERMINAL
           PCB TERMINAL
        FACTORY WIRING (115VAC)
        FACTORY WIRING (24VAC)
        FIELD WIRING (115VAC)
        FIELD WIRING (24VAC)
      CONDUCTOR ON PCB
             FIELD WIRING TERMINAL
           FIELD EARTH GROUND
          EQUIPMENT GROUND
      FIELD SPLICE
     PLUG RECEPTACLE

A00197

Fig. 15—Wiring Diagram

SERVICE

If status code recall is needed, do not remove power or blower door. Briefly remove and then reconnect one main limit wire to display stored status code.
LED CODE| STATUS
CONTINUOUS OFF –| Check for 115VAC at L1 and L2, and 24VAC at SEC-1 and SEC-2.
CONTINUOUS ON –| Control has 24VAC power.
RAPID FLASHING –| Line voltage (115VAC) polarity reversed. If twinned, refer to twinning kit instructions.
EACH OF THE FOLLOWING STATUS CODES IS A TWO DIGIT NUMBER WITH THE FIRST DIGIT DETERMINED BY THE NUMBER OF SHORT FLASHES AND THE SECOND DIGIT BY THE NUMBER OF LONG FLASHES.
11 NO PREVIOUS CODE – Stored status codes are erased when power (115VAC or 24VAC) to control is interrupted or 48 hours after each fault is cleared.
12 BLOWER ON AFTER POWER UP (115 VAC or 24 VAC)   -Blower runs for 90 seconds, if unit is powered up during a call for heat (R-W closed).
13 LIMIT OR FLAME ROLL-OUT SWITCH LOCKOUT – Control will auto reset after three hours. Reset switch or replace fuse link. Refer to #33.
14 IGNITION LOCKOUT – Control will auto-reset after three hours. Refer to

34.

21 GAS HEATING LOCKOUT    – Control will NOT auto reset.
Check for: – Mis-wired gas valve      -Defective control (valve relay)
22 ABNORMAL FLAME-PROVING SIGNAL    – Flame is proved while gas valve is de-energized. Inducer will run until fault is cleared.
Check for:   – Leaky gas valve     -Stuck-open gas valve
23 PRESSURE SWITCH DID NOT OPEN    Check for:
– Obstructed pressure tubing.    – Pressure switch stuck closed.
24 SECONDARY VOLTAGE FUSE IS OPEN
Check for: – Short circuit in secondary voltage (24VAC) wiring.
31 PRESSURE, DRAFT SAFEGUARD , AUX-LIMIT SWITCH (when used*) OR BLOCKED VENT SWITCH (when used) DID NOT CLOSE OR REOPENED
(DOWNFLOW ONLY*)* If open longer than five minutes, inducer shuts off for 15 minutes before retry.  Check for:  – Proper vent sizing
– Low inducer voltage (115VAC)                – Defective inducer motor
- Defective Blower motor or capacitor     – Restricted vent
– Defective pressure switch                        – Excessive wind
– Inadequate combustion air supply
– Disconnected or obstructed pressure tubing
If it opens after trial for ignition period, blower will come on for 90 second recycle delay.
33 LIMIT OR FLAME ROLL-OUT SWITCH IS OPEN – If open longer than three minutes, code changes to #13. Flame roll-out switch requires manual reset.
Check for:  – Defective blower motor or capacitor.
– Dirty filter or restricted duct system.
– Loose blower wheel.
– Defective switch or connections.
– Inadequate combustion air supply (Flame Roll-out Switch or fuse link open).
– Open Flame Roll-out switch, or fuse link. Manual reset or replace.
34 IGNITION PROVING FAILURE – Control will try three more times before lockout #14 occurs. If flame signal lost after trial for ignition period, blower will come on for 90 second recycle delay. Check for:
– Oxide buildup on flame sensor (clean with fine steel wool).
– Proper flame sense microamps (.5 microamps D.C. min., 4.0 – 6.0 nominal).
– Gas valve defective or gas valve turned off.
– Defective Hot Surface Ignitor          – Manual valve shut-off.
– Low inlet gas pressure.                     – Control ground continuity
– Green wire MUST be connected to furnace sheet metal.
– Inadequate flame carryover or rough ignition.
– Flame sensor must be ungrounded.
COMPONENT TEST**
To initiate the component test sequence, shut OFF the room thermostat or disconnect the “R” thermostat lead. Briefly short the TEST terminal to the “Com 24V” terminal. Status LED will flash code and then turn ON the inducer motor. The inducer motor will run for the entire component test. The hot surface ignitor, blower motor-heat speed, and blower motor-cool speed will be turned ON for 10-15 seconds each. Gas Valve and Humidifier will not be turned on.

320615-102 REV. K

A00307

Fig. 16—Service Label

Troubleshooting Guide

A99123a

A99123b

WARNING

Blower access panel door switch opens 115-v power to control center. No component operation can occur. Caution must be taken when manually closing this switch for service purposes. Failure to follow this warning could result in electrical shock, personal injury, or death.

4. BRIEFLY short (jumper) TEST, 1/4-in. quick-connect terminal on control center (adjacent to the LED diagnostic light) and the COM terminal on thermostat connection block. (See Fig. 12.)

NOTE: If TEST to COM terminals are jumpered longer than 2 sec, LED will flash rapidly, and retrieval request will be ignored.

5. When above items have been completed, the component test sequence will occur as described in the Component Test Sequence section above.

NOTE: Be sure to record the status code which is flashed 4 times at start of component test for further troubleshooting.

6. After component test is completed and furnace is operating properly, release blower access panel door switch, replace blower access panel, and replace main furnace door.

SERVICE TRAINING

Packaged Service Training programs are an excellent way to increase your knowledge of the equipment discussed in this manual, including:

• Unit Familiarization          • Maintenance
• Installation Overview       • Operating Sequence

A large selection of product, theory, and skills programs is available, using popular video-based formats and materials. All include video and/or slides, plus companion book.

Classroom Service Training plus “hands-on” the products in our labs can mean increased confidence that really pays dividends in faster troubleshooting, fewer callbacks. Course descriptions and schedules are in our catalog.

CALL FOR FREE CATALOG 1-800-962-9212

[ ] Packaged Service Training       [ ] Classroom Service Training

A94328

Copyright 2000 CARRIER Corp. • 7310 W. Morris St. • Indianapolis, IN 46231 58MSA4SM

Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.

PC 101     Catalog No. 535-80007    Printed in U.S.A.    Form 58MSA-4SM 10-00     Replaces: 58MSA-3SM

References

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