Goodman GMVC960803BN Error Code Eb6: Over/Under Voltage Trip or Over Temperature Trip
What Does Code Eb6 Mean?
Error code Eb6 on the Goodman GMVC960803BN indicates that the ECM circulator blower motor's internal protection circuits have shut the motor down due to one of three conditions: line voltage that is too high, line voltage that is too low, or overheating of the motor's power module.
ECM motors operate within a specific voltage range. When the AC line voltage to the furnace exceeds approximately 140VAC or drops below approximately 70VAC, the motor's power electronics can be damaged and the motor will shut down to protect itself. Power quality problems in a home — such as a utility voltage surge, a shared circuit under heavy load, or a failing neutral connection — can push voltage outside this range. High ambient temperatures in the mechanical room, inadequate clearances around the furnace, or a defective motor power module can cause the module itself to overheat and trigger the over-temperature shutdown.
An electrician should measure the line voltage at the furnace disconnect and verify it is within the 108–132VAC normal range. An HVAC technician should assess the installation environment for ventilation issues and test the motor's condition. If the voltage and environment are normal and Eb6 persists, the ECM motor module may have failed.
Common Causes
When to Call a Professional
Contact a licensed HVAC technician if:
- Eb6 recurs after a short rest period — an electrician must measure line voltage at the furnace disconnect to rule out a power supply problem
- The mechanical room has high ambient temperatures or poor ventilation — an HVAC technician must assess installation conditions
- Line voltage and temperature are normal but Eb6 persists — the ECM motor module requires professional testing and possible replacement
✓ Verified against manufacturer service manual — March 2026