HVAC Code Lookup

Trane fault codes

38 documented codes for Trane furnaces, each cited to the manufacturer's own manual. Trane and American Standard are both Trane Technologies brands and share the same integrated furnace control (IFC) platforms. Older induced-draft and condensing furnaces (XR80/XR95/XV80/XV95 era) use a single red diagnostic LED that blinks a count; current S-series furnaces (S8B1, S8V2, S9X1/S9X2, S9V2, S9V2-VS) use a two/three-character seven-segment display showing E-codes. American Standard's equivalent models (A801X, A951X, Silver/Gold/Platinum 80 and 95) use the same tables with brand-specific wording..

Furnace codes

CodeMeaningSeverity
Flashing SlowRed LED flashing slowly and steadilyNormal standbyStatus
Flashing FastRed LED flashing rapidly and steadilyNormal operation with an active call for heatStatus
Continuous ONLED on solid, never blinkingThe integrated furnace controlHard lockout
Continuous OFFLED completely darkThe control board is not receiving powerWarning
2 Flashes2 flashes, pause, repeatSystem lockoutHard lockout
3 Flashes3 flashes, pause, repeatDraft pressure errorSoft lockout
4 Flashes4 flashes, pause, repeatOpen high limit deviceSoft lockout
5 Flashes5 flashes, pause, repeatFlame is being detected when there should be no flame presentSafety fault
6 Flashes6 flashes, pause, repeatThe 115 volt AC line and neutral are reversed at the furnace, or the furnace is poorly groundedWarning
7 Flashes7 flashes, pause, repeatGas valve circuit errorSafety fault
8 Flashes8 flashes, pause, repeatLow flame sense signalWarning
9 Flashes9 flashes, pause, repeatThe control is directing the technician to check the igniter circuit and the voltage between line neutral and 24VAC common, which points at an igniter or grounding problemWarning
E01Internal integrated furnace control failureHard lockout
E2.1Retry exceededHard lockout
E2.2Recycles exceededHard lockout
E2.3The control commanded the first-stage gas valve on and the valve did not energize, ten times in a rowHard lockout
E3.1The first-stage pressure switch is reading closed when the control expects it to be open, which the control calls a shorted pressure switchSoft lockout
E3.2The first-stage pressure switch will not close, so the control cannot prove the draft inducer is moving flue gas and will not open the gas valveSoft lockout
E3.3The second-stage pressure switch is reading closed when the control expects it to be openSoft lockout
E3.4The second-stage pressure switch will not close, so the furnace cannot go to high fireSoft lockout
E04A safety limit has opened: the main thermal limit, a flame rollout switch, or the reverse airflow switchSafety fault
E4.0The high limit switch has opened because the furnace overheatedSoft lockout
E4.1The reverse air-flow limit switch has opened, meaning air is moving through the furnace the wrong way or a downflow/horizontal airflow fault has been sensedSafety fault
E4.2The flame roll-out limit switch has openedSafety fault
E05The control is sensing a flame when there should not be one - for example with the gas valve commanded offSafety fault
E06Line voltage polarity is reversed at the furnace, or the furnace is not properly groundedWarning
E6.1Line and neutral are reversed in the 115 volt supply to the furnaceWarning
E6.2The furnace does not have a good electrical ground, which the control needs in order to sense flame reliablyWarning
E6.3Igniter faultHard lockout
E7.1The first-stage gas valve is energized when the control has commanded it offSafety fault
E7.2The redundant safety relay on the controlSafety fault
E08The flame current the control reads is low but still high enough to keep runningWarning
E09The inducer limit switch or the condensate pressure switch is openSoft lockout
E10The control is not getting a response from the variable-speed inducer motor, or the two microcontrollers on the board cannot talk to each otherHard lockout
E11Gas valve relay faultSafety fault
E12The 5 amp fuse on the integrated furnace control has opened, so 24 volt control power is lostHard lockout
E13The blower motor's horsepower or OEM ID does not match what the furnace's personality module expectsHard lockout
E17The control is not getting a response from the ECM blower motor, so the indoor blower will not runHard lockout

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Manuals used for this page