Error code reference

Trane Furnace Error Code 6

1st stage pressure switch has opened 5 times within one cycle: 1 hour lockout.

SourceTrane Furnace - Service Manual: UD2/DD2 Two-Stage Induced Draftp. 11, 16, 20

Diagnostic procedure

The full 6 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
Follow same troubleshooting as 3 flash fault (1st stage pressure switch fault); verify wiring, inducer motor operation, and pressure readings.

SourceTrane Furnace - Service Manual: UD2/DD2 Two-Stage Induced Draftp. 11, 16, 20

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

2 manuals in the MyPros+ library document this code for Trane furnace.

Models covered by the manuals that document this code

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