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Error code reference
Trane Furnace Error Code 5 Flash
Flame detect fault - flame is sensed when it should not be present.
SourceTrane XC80 Furnace - Service Manual: Variable Speed 2-Stagep. 30, 43
Diagnostic procedure
The full 5 Flash procedure
Step 1 is visible so you can confirm you are on the right page. The remaining steps, the ones that tell you whether to actually replace a part, unlock with any pass.
MyPros+ · DiagnosticsStep 1 preview
1
First diagnostic step
Disconnect electrical power to furnace; turn off gas supply and remove gas valve to inspect for moisture or debris in inlet gas screen.
SourceTrane XC80 Furnace - Service Manual: Variable Speed 2-Stagep. 30, 43
More steps, wiring diagram references, and verified part numbers
Includes expected resistance and voltage values, connector pinouts, and supersession notes for replacement parts.
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Where this code is documented
3 manuals in the MyPros+ library document this code for Trane furnace.
Models covered by the manuals that document this code
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