Error Code E 205
High

Lennox EL296UHV Error Code E 205: Gas Valve Control Relay Contact Shorted

TL;DR
Your Lennox EL296UHV has detected a shorted gas valve relay contact on the control board. The furnace needs professional repair before it can operate safely.
Disclaimer
This article is for informational purposes only and does not guarantee the accuracy or completeness of the information provided. Always turn off power and gas supply before attempting any repairs. If you smell gas, leave immediately and call your gas company. Consult a licensed HVAC technician for diagnosis and repair. Any actions taken based on this information are at your own risk.

What Does Code E 205 Mean?

Error code E205 on the Lennox EL296UHV indicates that the gas valve control relay on the control board has a shorted contact. The relay is the electronic switch that the control board uses to open and close the gas valve during normal operation, and a short in this component means the gas valve circuit is no longer being controlled properly.

A shorted relay contact can cause the gas valve to remain energized even when the control board is not commanding heat, which is a serious safety concern. The board detects this condition during its self-check and locks out the system to prevent uncontrolled gas flow.

A technician needs to first check the wiring between the control board and the gas valve to rule out a wiring issue. If the wiring is correct, the control board itself must be replaced, as the relay is a component soldered to the board and cannot be repaired individually.

When to Call a Professional

Contact a licensed HVAC technician if:

Sources

  1. Lennox EL296UHV Unit Information (Corp. 1125-L5)

✓ Verified against manufacturer service manual — March 2026