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Error code reference
Lennox Furnace Error Code E 271
Soft lockout - Exceeded maximum number of retries, last retry failed due to the pressure switch opening.
SourceLennox EL296UHE - Service Manual: High-Efficiency Gas Furnacep. 13
Diagnostic procedure
The full E 271 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
Check pressure (inches w.c.) of low pressure switch closing on heat call. Measure operating pressure. Inspect vent and combustion air inducer for correct operation and restriction. Clears when heat call finishes successfully.
SourceLennox EL296UHE - Service Manual: High-Efficiency Gas Furnacep. 13
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 Lennox furnace.
Models covered by the manuals that document this code
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