ErrorCodePro · Appliance Error CodesLennox Furnace Error Codes: Full List & Meanings
Every Lennox furnace error code we have verified against Lennox's own support pages, with its official meaning. This list covers sl280dfv surelight gas furnaces (service literature 1117-l4). Codes vary by model, so confirm in your owner's manual. Support: Lennox dealer (lennox.com).
Smell gas? Leave the building now. Do not touch light switches, phones or appliances inside. Call your gas utility or 911 from outside. CO alarm sounding or headache, dizziness or nausea? Get everyone outside and call 911. Gas valves, burners, venting and wiring are for a licensed technician only. See our safety policy.
Codes by system
Heating
Venting / airflow
All Lennox furnace error codes
Codes marked "Reset only" or "Service" have no separate page because the manufacturer publishes no owner fix beyond a reset or a service call.
| Code | Official meaning | System | Owner action |
|---|---|---|---|
| E291 | Heating airflow is below the minimum. Lennox says check for a dirty filter and airflow restriction. The furnace goes into a 1-hour soft lockout. | Heating | Owner checks |
| E250 | The limit circuit is open. Lennox checks airflow and blockages. If it doesn't close within 3 minutes there's a 1-hour soft lockout. | Heating | Owner checks |
| E223 | The low pressure switch didn't close. Lennox inspects the vent and combustion air inducer for restriction. Also: E227 | Venting / airflow | Owner checks |
| E270 | Maximum ignition retries were exceeded with no flame current. Lennox checks gas flow, the ignitor and the flame sensor. | Heating | Owner checks |
| E312 | Warning only: the blower runs at reduced airflow because static pressure is too high. | Heating | Owner checks |
| E200 | The manufacturer lists E200 as: hard lockout: rollout circuit open or previously open (combustion/venting problem, CO risk). A licensed HVAC technician must diagnose this. | Heating | Service |
| E241 | The manufacturer lists E241 as: flame sensed out of sequence (shut off gas and call a technician). A licensed HVAC technician must diagnose this. | Heating | Service |
| E204 | The manufacturer lists E204 as: gas valve mis-wired. A licensed HVAC technician must diagnose this. | Control / electronics | Service |
| E207 | The manufacturer lists E207 as: hot surface ignitor sensed open. A licensed HVAC technician must diagnose this. | Control / electronics | Service |
| E224 | The manufacturer lists E224 as: low pressure switch failed closed. A licensed HVAC technician must diagnose this. | Control / electronics | Service |
| E225 | The manufacturer lists E225 as: high pressure switch failed open. A licensed HVAC technician must diagnose this. | Control / electronics | Service |
| E228 | The manufacturer lists E228 as: combustion air inducer calibration failure. A licensed HVAC technician must diagnose this. | Control / electronics | Service |
| E240 | The manufacturer lists E240 as: low flame current (run mode). A licensed HVAC technician must diagnose this. | Sensors | Service |
| E290 | The manufacturer lists E290 as: ignitor circuit fault. A licensed HVAC technician must diagnose this. | Control / electronics | Service |
| E292 | The manufacturer lists E292 as: indoor blower motor unable to start. A licensed HVAC technician must diagnose this. | Control / electronics | Service |
| E294 | The manufacturer lists E294 as: combustion air inducer over current. A licensed HVAC technician must diagnose this. | Control / electronics | Service |
| E110 | The manufacturer lists E110 as: low line voltage. A licensed HVAC technician must diagnose this. | Power supply | Service |
| E111 | The manufacturer lists E111 as: line voltage polarity reversed. A licensed HVAC technician must diagnose this. | Power supply | Service |
| E112 | The manufacturer lists E112 as: ground not detected. A licensed HVAC technician must diagnose this. | Power supply | Service |
| E370 | The blower door interlock is open. The alarm clears when the door switch closes or after a power reset. Make sure the blower door is fully seated. | Door / lock | Service |
Symptoms
Sources
Last reviewed: October 20, 2026. ErrorCodePro is not affiliated with Lennox.