Lennox EL296UHV Error Code E 271: Soft Lockout - Pressure Switch Retry Failed
What Does Code E 271 Mean?
Error code E271 on the Lennox EL296UHV indicates a soft lockout after the furnace exceeded the maximum number of ignition retries, with the last retry failing because the pressure switch opened. The furnace tried to start multiple times, but the pressure switch could not stay closed long enough to complete the ignition sequence.
The pressure switch is a safety device that verifies the combustion air inducer is creating sufficient draft to safely vent combustion gases. If the switch opens during the trial for ignition, the control board aborts the ignition attempt because safe venting cannot be confirmed. After multiple failed attempts, the system enters soft lockout.
Common causes include blockages in the exhaust vent or combustion air intake (ice, debris, bird nests), a weakening inducer motor that cannot maintain adequate draft, water-logged or cracked pressure switch hoses, or a pressure switch that is failing intermittently. The lockout clears when a subsequent heating call completes successfully.
When to Call a Professional
Contact a licensed HVAC technician if:
- The furnace is not heating due to repeated pressure switch failures
- You have checked the outdoor vent terminations and found no blockages
- E271 occurs frequently, especially during cold or windy weather
- The inducer motor sounds abnormal or inconsistent
✓ Verified against manufacturer service manual — March 2026