Trane Furnace Troubleshooting

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.

Step 1
At first, look at the settings and choose the “heat” mode. In case your Trane furnace is equipped with a “fan” mode, switch it on as well. If you don’t feel the heat coming out of the furnace, you need to significantly increase the output temperature – it has to be way higher than the indoor temperature. Address your device’s manual and find troubleshooting section to learn which temperature setting you need to choose.
Step 2
If your device refuses to operate normally, you need to reset it. Most models are equipped with a reset button which you only need to press for a couple of seconds. If your model doesn’t have any, open your device’s manual and find the information on how to do that.
Step 3
Finally, the vents may have been blocked by some obstructions including furniture, toys or some other items that prevent the normal airflow which is a prerequisite for normal operation of any Trane heating system.

Trane Gune SVX001A Furnace Troubleshooting

SymptomsPossible 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.

Trane UC Series Furnace Troubleshooting

Problem Solution
EXCESSIVE COMBUSTION PRESSURE (WIND IN EXCESS OF 40 MP.H.) VENT OR FLUE BLOCKAGEIf 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 FLAMIf 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 FAILUREIf 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 FAILUREIf 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 FAILUREIf 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 BLOCKAGEIf 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 LOCKOUTWhen 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 SHUTDOWNIf 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.

Trane UC1 Furnace Troubleshooting

ProblemPossible TroublePossible 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. Lockout7. 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 NoiseCall your servicer

Trane UD2B060A9V3VB Furnace Troubleshooting

GREEN LED FLASHAMBER LED FLASHRED LED FLASHERROR
1Flame Sensed when no flame should be present
2Pressure switch stuck closed
31st stage pressure switch is open / not closing
4Open thermal limit or open rollout
5Open low voltage fuse
61st stage pressure switch opened 5 times within one cycle--1 hour lockout
7System lockout Retry
8System lockout Recycle
9Reverse polarity or poor grounding
10Gas valve energized without call for heat
12Ignitor relay failure internal in board. Replace IFC
SolidGas valve relay failure internal in board. Replace IFC
3 Double2nd stage pressure switch open; system reverts back to 1st stage heat
11st stage call for heat
22nd stage call for heat
3W2 call present without W1
4Y call present without G
RapidLow flame sense current
1Standby mode or call for cooling

Trane UH2B060A9V3VA Furnace Troubleshooting

LED FLASH CODESINTEGRATED FURNACE CONTROL
RED LED - LitePort ™DATA -1 FLASH EVERY 20 SECONDS
2 FlashesRETRIES 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 FlashNORMAL. NO CALL FOR HEAT
Fast FlashNORMAL. CALL FOR HEAT PRESENT
GREEN and REDFUSE OPEN OR INTERNAL CONTROL FAILURE

Trane UHMB060ACV3VB Furnace Troubleshooting

Fault LEDUser Interface DisplayAlert GroupAlert Description
2 FlashRECYCLEFlame lost or Ignition failureFlame is off when flame should be detected. Furnace tries to relight itself.
RETRYFurnace tries to light, but no flame is detected.
RECYCLE LOSoft lockout due to flame lost or ignition retries10 recycles within a single call for heat will cause 1hr lockout.
RETRY LO3 ignition attempts in a row within a single call for heat results in 1 hr lockout.
3 FlashPS3 OPENPressure Switch FailureOpen Pressure Switch, third staqe
PS3 CLOSEDShorted Pressure Switch, third stage
PS2 OPENOpen Pressure Switch, second stage
PS2 CLOSEDShorted Pressure Switch, second staqe
PS1 OPENOpen Pressure Switch, first stage
PS1 CLOSEDShorted Pressure Switch, first stage
4 FlashAUX LIMITHigh Temp Limit FaultOpen Reverse Flow - Heat exchanger temperature too high. Could be caused by low airflow or fan failure.
HIGH LIMITOpen High Limit - Heat exchanger temperature too high. Could be caused by low airflow or fan failure.
ROLLOUT OPENRoll Out FaultOpen flame rollout
5 FlashFLAME ERRORFlame Detect FaultFlame detected, should not be present
6 FlashPOLARITY ERRLine Polarity FaultVoltaqe reverse polarity
GND FAULTGround FaultOccurs when proper earth ground is not detected.
IGNITER ERRIgnition Means FaultIqniter fault
TRIAC ERRTriac fault
7 FlashEXT GV ERRGas Valve FaultControl senses 24V present at the gas valve when it should not be present.
Solid ONINT GV ERRControl 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 FlashLO FLAME SNSLow Flame SignalFlame current is low. but still strong enouqh to allow operation.
9 FlashIND LIMITHigh Temp Limit FaultFlue gas temperature too high. Could be caused by low airflow or fan failure.