10 red flashes
Gas valve energized with no call for heat
This code typically points to
- Gas-valve wiring problem
- Gas valve fault
Next checks to confirm
- Verify unwanted valve power
- Inspect wiring
- Replace valve/control only after verifying circuit
Escalation
Ignition sequence inhibited while fault exists; safety concern.
Reset behavior
Inducer and blower run, ignition inhibited.
Safety Critical
Immediate concern