Lennox EL296UHV Error Code E 290: Ignitor Circuit Fault
What Does Code E 290 Mean?
Error code E290 on the Lennox EL296UHV indicates an ignitor circuit fault — either the hot surface ignitor itself has failed, or the triggering circuitry on the control board that powers the ignitor is malfunctioning. The furnace enters a 1-hour soft lockout.
The control board monitors the ignitor circuit for proper resistance and current draw. When the ignitor is commanded to energize, the board expects to see a specific electrical signature. If the ignitor draws too little current (cracked element), too much current (shorted), or the board's own ignitor relay fails, the system flags E290 rather than continuing to attempt ignition with a defective circuit.
The lockout clears when a stable flame is proven after the lockout period. A technician should measure the hot surface ignitor's resistance and compare it to the specification in the installation manual. If the ignitor is within spec, the issue may be with the control board's ignitor triggering circuitry, which would require a board replacement.
Common Causes
| Cause | Likelihood | DIY? |
|---|---|---|
| Failed hot surface ignitor | Most common | ✗ Call a pro → |
When to Call a Professional
Contact a licensed HVAC technician if:
- The furnace is not heating and shows E290
- The ignitor needs to be tested and likely replaced
- E290 returns after the 1-hour lockout clears
- The ignitor tests good but E290 still appears, suggesting a control board issue
✓ Verified against manufacturer service manual — March 2026