Lennox Furnace Code E205
Safety fault
The gas valve control relay contact on the board is shorted, meaning the control cannot reliably shut the gas valve off through that relay.
Manual wording: “Gas valve control relay contact shorted. Check wiring on control and gas valve. If wiring is correct, replace control.”
Documented for: EL296UHE and SLP98UHV series
Likely causes, most common first
- Failed gas valve relay on the integrated control board
- Incorrect wiring at the control or gas valve
When to call a technician
The manual's action is to check the wiring on the control and gas valve and, if the wiring is correct, replace the control. A shorted gas valve relay is a safety-critical failure. Turn the furnace off and call a technician.
A Lennox furnace throwing this code repeatedly has a reason — clearing the code without fixing the cause just hides it.
Sources
- EL296UHE Service Literature (Corp. 1246-L10), Table 4 - Integrated Control Diagnostic Codes (Lennox Industries Inc., EL296UHE series 96% AFUE two-stage upflow/horizontal gas furnace (EL296UH045XE36B, EL296UH070XE36B, EL296UH090XE48C)) · checked 2026-08-25
- SLP98UHV Service Literature (Corp. 1029-L7), Table 14 - LED 7 Segment Status / Error Code and Integrated Control Diagnostic Codes (Lennox Industries Inc., SLP98UHV series variable-capacity communicating gas furnace (66,000-132,000 Btuh)) · checked 2026-08-25