Lennox EL296UHV Error Code E 272: Soft Lockout - Pressure Switch Recycle Failed
What Does Code E 272 Mean?
Error code E272 on the Lennox EL296UHV indicates a soft lockout after the furnace exceeded the maximum number of recycles, with the last recycle caused by the pressure switch opening during operation. Unlike E271 where the switch opens during ignition attempts, E272 means the furnace successfully lit but the pressure switch opened while the burners were running.
When the pressure switch opens during active combustion, the control board immediately shuts off the gas valve for safety. The furnace then attempts to restart (recycle). If the pressure switch keeps opening during these restart attempts, the system exhausts its recycle limit and enters soft lockout.
This pattern — successful ignition followed by pressure switch opening — often points to causes that worsen as the furnace runs. A vent pipe that allows initial airflow but restricts as the system heats up, condensation building up in the pressure switch hose during operation, or an inducer motor that slows down as it warms up can all cause this behavior. A technician needs to inspect the pressure switches, vent system, and inducer for the root cause.
When to Call a Professional
Contact a licensed HVAC technician if:
- The furnace ignites but shuts down after running briefly
- E272 appears repeatedly across multiple heating cycles
- The vent termination appears clear but the problem persists
- You also see E227 (pressure switch opening during operation) in the error history
✓ Verified against manufacturer service manual — March 2026