Goodman GMEC960803BN Error Code Red 10 Flashes: Gas Flow With No Call for Heat
What Does Code Red 10 Flashes Mean?
Ten red flashes on the Goodman GMEC960803BN control board indicate that the control module detected current flowing to the gas valve when no call for heat was active. This is a serious safety condition because gas should never flow unless the control board has initiated a proper ignition sequence.
The most common cause is an electrical short somewhere in the gas valve wiring that is sending voltage to the valve independently of the control board's commands. This could be a damaged wire touching a live terminal, a connector that has come loose and is making contact with the wrong pin, or internal wiring damage.
If the gas valve wiring checks out as correct with no shorts or loose connections, the control board itself is likely at fault — an internal relay may be sending voltage to the gas valve circuit unexpectedly. In either case, this condition requires immediate attention. Turn off the gas supply valve and shut off the furnace at the circuit breaker until a technician can diagnose the issue.
Common Causes
| Cause | Likelihood | DIY? |
|---|---|---|
| Electrical short sending voltage to gas valve | Most common | ✗ Call a pro → |
| Faulty control board | Common | ✗ Call a pro → |
When to Call a Professional
Contact a licensed HVAC technician if:
- The furnace shows 10 red flashes — call immediately
- You smell gas near the furnace when it is not running
- The gas valve appears to be energized without a thermostat call
✓ Verified against manufacturer service manual — March 2026