Lennox EL296UHV Error Code E 270: Soft Lockout - Ignition Failure
What Does Code E 270 Mean?
Error code E270 on the Lennox EL296UHV indicates a soft lockout after the furnace exceeded the maximum number of ignition retries without the flame sensor detecting a flame. During each attempt, the control board energizes the hot surface ignitor, opens the gas valve, and waits for a flame signal. After exhausting all retries with no flame detected, the system enters soft lockout.
There are two main categories of causes. The burners may actually be lighting, but a dirty flame sensor cannot detect the flame — this is the single most common cause of E270. Alternatively, the burners may not be lighting at all, which points to a gas supply issue, a failed hot surface ignitor, or a gas valve problem.
The soft lockout clears when a subsequent heat call completes successfully. A technician should check flame sensor current using the control diagnostics, clean or replace the flame sensor, verify the ignitor glows during the ignition sequence, and confirm adequate gas supply and pressure.
Common Causes
| Cause | Likelihood | DIY? |
|---|---|---|
| Dirty or failed flame sensor | Most common | ✗ Call a pro → |
| Failed hot surface ignitor | Common | ✗ Call a pro → |
When to Call a Professional
Contact a licensed HVAC technician if:
- The furnace is not heating and shows E270
- The burners are not igniting at all during the startup sequence
- The ignitor does not glow when the furnace attempts to start
- E270 keeps recurring after the lockout clears
✓ Verified against manufacturer service manual — March 2026