Some models of Trane electric furnaces like XB90 can produce up to 113,000 units of heat which is more than enough for any typical house. Meeting Energy Star international standards, these electric furnaces are capable of heating areas of any size. Trane appliances are very reliable and efficient and can serve for many years, but even these furnaces are not immune to various breakages and malfunctions. Don’t rush to call a licensed HVAC technician or seek for any other professional help in case your furnace doesn’t heat well – at first, read these troubleshooting guidelines.
| Symptoms | Possible Cause(s) | Corrective Action |
|---|---|---|
| Flame pops back. | Burner orifice too small. | Check with local gas supplier for proper orifice size and replace. |
| Noisy flame. | Irregular orifice causing whistle or resonance. | Replace orifice. |
| Excessive gas input. | Test and reset manifold pressure | |
| Yellow tip flame. | Clogged main burners. | Clean main burner ports. |
| Note: Some yellow tipping on LP gas is permissible. | Misaligned orifices. | Replace manifold assembly. |
| Insufficient combustion air. | ||
| Unit possibly over fired. | Check gas input and manifold pressures. | |
| Partially blocked flue vent pipe. | Check flue vent pipe and clear as needed. | |
| Floating flame. | Blocked venting. | |
| Insufficient combustion air. | Check combustion air inlet openings and/or vent pipe and clear as needed. | |
| Blocked heat exchanger. | Clean heat exchanger. | |
| Air leak into combustion chamber or flue collector. | Check flue collector and clear as needed. | |
| Gas odor. | Gas leak. Shut off gas supply immediately! | Inspect all gas piping and repair accordingly. |
| Shut off gas supply immediately! | Leaking gas test port on valve. | Check to ensure gas test ports are sealed. |
| Blocked heat exchanger. | Clean heat exchanger. | |
| Blocked flue collector. | Check flue collector and clear as needed. | |
| Negative pressure in the building. | ||
| Delayed ignition. | Improper ground. | Check grounding wires and spark ignitor connections. |
| Bad or broken spark cable. | Inspect spark cable connections andcuts. Replace if necessary. | |
| Faulty control board. | Check to ensure spark ignitor is energized after pre-purge period. | |
| Pressure regulator set too low. | Test and reset manifold pressure | |
| Main burner orifices dirty. | Clean or replace orifices. | |
| Improper venting. | ||
| Failure to ignite. | Gas leak. Shut off gas supply immediately! | Open all manual valves, check for leaks. Inspect all gas piping and repair accordingly. |
| No power supply to the unit. | Turn on power supply, check fuses and replace if bad. | |
| Thermostat not calling. | Turn up thermostat. Check for 24 V on terminals R and W1 on terminal strip. | |
| Defective high limit switch. | Check switch for continuity if open with no heat present; replace. | |
| Defective air pressure switch. | Check switch operation to ensure switch closes after power vent purge period. If it does not make, check tubing connections for blockage. | |
| Defective spark ignitor, gas valve, thermostat or transformer. | Check for continuity and voltage in safety and control circuits; replace an item where continuity or voltage not found. | |
| Loose wiring. | Check all wiring per diagram. | |
| Improper ground. | Check all ground wires and connections. | |
| Improper thermostat or transformer wiring. | Check both for wiring according to diagram. | |
| Condensation. | Improper venting. | |
| Unit under fired. | Check gas supply pressures to the unit. | |
| Building/space too cold. | A minimum of 50°F (10°C) thermostat setting must be maintained to deter formation of condensation. | |
| Burners will not shut off. | Thermostat located improperly. | Relocate thermostat away from outside wall or drafts. |
| Improper thermostat wiring. | Check thermostat circuit for open and close on heater terminal strip K R" and W W." | |
| Shorted circuit. | Check thermostat circuit for shorts or any staples piercing wires. | |
| Defective thermostat. | If thermostat is calling after set point has been satisfied, replace. | |
| Defective/sticking gas valve. | Check for 24 V on gas valve terminals when thermostat not calling. Replace if necessary. | |
| Defective control board. | Check for 24 V at terminals "R" and "W." If not present and board is not in flash code mode, replace board. | |
| Excessive gas supply pressure. | ||
| Rapid burner cycling. | Loose electrical connections at thermostat or gas valve. | Tighten all electrical connections. |
| Unit cycling on high limit. | Check for proper air supply across heat exchanger and proper gas supply. | |
| Thermostat located improperly. | Relocate thermostat away from outside wall or drafts. | |
| Defective high limit switch. | Jumper high limit switch wiring (orange and yellow wires). If burner operating normally, replace switch. | |
| Not enough heat. | Incorrect gas input. | |
| Unit undersized. | Is the unit output sized correctly for the heat loss of the space? Has the space been enlarged? Is the unit located in the space properly | |
| Thermostat malfunction. | Check thermostat circuit; 24 V on terminals "R" and "W" on terminal strip. | |
| Unit cycling on high limit. | Check air movement across the heat exchanger. Check gas input to ensure unit is not over fired. Check heat exchanger to ensure unit is not dirty. |
| Problem | Solution |
|---|---|
| EXCESSIVE COMBUSTION PRESSURE (WIND IN EXCESS OF 40 MP.H.) VENT OR FLUE BLOCKAGE | If pressure against induced draft blower outlet becomes excessive, the pressure switch will open and shut off the gas valve until acceptable combustion pressure is again available |
| LOSS OF FLAM | If loss of flame occurs during a heating cycle, or flame is not present at the sensor, the flame control module will close the gas valve. The flame control module will then recycle the ignition sequence, then if ignition is not achieved, it will shut off the gas valve and lock out the system. |
| POWER FAILURE | If there is a power failure during a heating cycle, the system will restart the ignition sequence automatically when power is restored, if the thermostat still calls for heat |
| GAS SUPPLY FAILURE | If loss of flame occurs during a heating cycle, the system integrated control module will recycle the ignition sequence, than if ignition is not achieved, the integrated control module will shut off the gas valve and lock out the system. |
| INDUCED DRAFT BLOWER FAILURE | If pressure is not sensed by the pressure switch, the contacts will remain open and not allow the gas valve to open, therefore the unit will not start. If failure occurs during a running cycle, the pressure switch contacts will open and the gas valve will close to shut the unit down. |
| CONDENSATE DRAIN BLOCKAGE | If the condensate drain is blocked, either by debris, im- proper draining, or by freezing condensate, the pressure switch will sense the accumulation of condensate in the furnace drain pan. The pressure switch contacts will open and remain open, not allowing unit operation. The unit will not operate until the condensate drain has been cleared, and the condensate flows freely |
| RESET AFTER LOCKOUT | When the integrated control module has shut the system down and gone into lockout, the system must be manually reset before the unit will restart. To reset, turn the system power off, then on, then off and then on again within 30 seconds. This may be done at the unit’s power source or at the thermostat. The system will not reset unless the procedure off-on-off-on is completed within 30 seconds. |
| RESET AFTER BURNER BOX LIMIT SHUTDOWN | If the furnace shuts down, one thing that can be checked is the burner box temperature limit switch. It is located on the bottom of the burner box. The vent and combustion air inlet terminations should be checked for blockage. If blockage exists, clear the problem and then the reset button may be depressed. |
| Problem | Possible Trouble | Possible Remedy |
|---|---|---|
| No Heating - Blower does not operate. | 1. Thermostat set incorrectly. | 1. Adjust thermostat. |
| 2. Blown fuse or tripped circuit breaker. | 2. Replace or reset protective device or call for servicer. | |
| 3. Defective component. | 3. Most controls are automatic and will recycle. If your unit still does not operate call for servicer. | |
| 4. Burner does not ignite. | 4. Call servicer. | |
| 5. Main gas line turned off. | 5. Have gas company check. | |
| 6. Blower door removed or ajar. | 6. Close door securely to restore power to blower and gas valve. | |
| 7. Lockout | 7. Turn power on-off-on-off twice in 30 seconds. | |
| Insufficient Heating - Blower operates continuously. | 1. Dirty air filters. | 1. Clean or replace filters. |
| 2. Blocked supply or return registers. | 2. Make sure registers are open and No obstacles blocking off the air. | |
| No Heat - Vent motor is running. | Restricted or plugged furnace Condensate drain. | 1. Remove drain clamps to condensate trap and drain pan outlet. |
| 2. Flush or clean drain blockage. | ||
| 3. Reinstall clamps. | ||
| Unusual Noise | Call your servicer |
| GREEN LED FLASH | AMBER LED FLASH | RED LED FLASH | ERROR |
|---|---|---|---|
| 1 | Flame Sensed when no flame should be present | ||
| 2 | Pressure switch stuck closed | ||
| 3 | 1st stage pressure switch is open / not closing | ||
| 4 | Open thermal limit or open rollout | ||
| 5 | Open low voltage fuse | ||
| 6 | 1st stage pressure switch opened 5 times within one cycle--1 hour lockout | ||
| 7 | System lockout Retry | ||
| 8 | System lockout Recycle | ||
| 9 | Reverse polarity or poor grounding | ||
| 10 | Gas valve energized without call for heat | ||
| 12 | Ignitor relay failure internal in board. Replace IFC | ||
| Solid | Gas valve relay failure internal in board. Replace IFC | ||
| 3 Double | 2nd stage pressure switch open; system reverts back to 1st stage heat | ||
| 1 | 1st stage call for heat | ||
| 2 | 2nd stage call for heat | ||
| 3 | W2 call present without W1 | ||
| 4 | Y call present without G | ||
| Rapid | Low flame sense current | ||
| 1 | Standby mode or call for cooling |
| LED FLASH CODES | INTEGRATED FURNACE CONTROL |
|---|---|
| RED LED - LitePort ™ | DATA -1 FLASH EVERY 20 SECONDS |
| 2 Flashes | RETRIES OR RECYCLES EXCEEDED |
| 3 Flashes | INDUCER OR PRESSURE SWITCH ERROR |
| 4 Flashes | OPEN LIMIT OR ROLLOUT SWITCH |
| 5 Flashes | FLAME SENSED WHEN NO FLAME SHOULD BE PRESENT |
| 6 Flashes | LINE REVERSE POLARITY |
| 7 Flashes | GAS VALVE CIRCUIT ERROR |
| 8 Flashes | WEAK FLAME |
| 9 Flashes | OPEN INDUCER LIMIT ERROR |
| Slow Flash | NORMAL. NO CALL FOR HEAT |
| Fast Flash | NORMAL. CALL FOR HEAT PRESENT |
| GREEN and RED | FUSE OPEN OR INTERNAL CONTROL FAILURE |
| Fault LED | User Interface Display | Alert Group | Alert Description |
|---|---|---|---|
| 2 Flash | RECYCLE | Flame lost or Ignition failure | Flame is off when flame should be detected. Furnace tries to relight itself. |
| RETRY | Furnace tries to light, but no flame is detected. | ||
| RECYCLE LO | Soft lockout due to flame lost or ignition retries | 10 recycles within a single call for heat will cause 1hr lockout. | |
| RETRY LO | 3 ignition attempts in a row within a single call for heat results in 1 hr lockout. | ||
| 3 Flash | PS3 OPEN | Pressure Switch Failure | Open Pressure Switch, third staqe |
| PS3 CLOSED | Shorted Pressure Switch, third stage | ||
| PS2 OPEN | Open Pressure Switch, second stage | ||
| PS2 CLOSED | Shorted Pressure Switch, second staqe | ||
| PS1 OPEN | Open Pressure Switch, first stage | ||
| PS1 CLOSED | Shorted Pressure Switch, first stage | ||
| 4 Flash | AUX LIMIT | High Temp Limit Fault | Open Reverse Flow - Heat exchanger temperature too high. Could be caused by low airflow or fan failure. |
| HIGH LIMIT | Open High Limit - Heat exchanger temperature too high. Could be caused by low airflow or fan failure. | ||
| ROLLOUT OPEN | Roll Out Fault | Open flame rollout | |
| 5 Flash | FLAME ERROR | Flame Detect Fault | Flame detected, should not be present |
| 6 Flash | POLARITY ERR | Line Polarity Fault | Voltaqe reverse polarity |
| GND FAULT | Ground Fault | Occurs when proper earth ground is not detected. | |
| IGNITER ERR | Ignition Means Fault | Iqniter fault | |
| TRIAC ERR | Triac fault | ||
| 7 Flash | EXT GV ERR | Gas Valve Fault | Control senses 24V present at the gas valve when it should not be present. |
| Solid ON | INT GV ERR | Control tried to turn on gas valve, but 24V not sensed. | |
| Control senses 24V present at the gas valve when it should not be present. | |||
| 8 Flash | LO FLAME SNS | Low Flame Signal | Flame current is low. but still strong enouqh to allow operation. |
| 9 Flash | IND LIMIT | High Temp Limit Fault | Flue gas temperature too high. Could be caused by low airflow or fan failure. |
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