Amana AMSS920803BN Error Code Continuous/Rapid Flash: Reversed Polarity
What Does Code Continuous/Rapid Flash Mean?
A continuous or rapid flash on the Amana AMSS920803BN's diagnostic LED means the 115-volt or 24-volt power supply has reversed polarity. The furnace will not operate in this condition because the control module requires correct polarity to function properly and to safely detect flame through the flame sensor circuit.
Reversed polarity means the hot (live) wire and the neutral wire are connected to the wrong terminals. This most commonly happens after electrical work on the furnace, such as a new installation, a control board replacement, or changes to the home's wiring. The 115V AC line and neutral may be swapped at the furnace connection, or the orange and gray transformer wires may be reversed on the control module.
A less common cause is a poor unit ground, which can also trigger this code. Regardless of the specific cause, this is an electrical wiring issue that must be corrected by a qualified electrician or HVAC technician with the power turned off. Working with electrical wiring while it is energized creates a serious shock hazard.
Common Causes
| Cause | Likelihood | DIY? |
|---|---|---|
| Reversed 115V AC line and neutral wires | Most common | ✗ Call a pro → |
| Reversed transformer wires (orange and gray) | Common | ✗ Call a pro → |
| Poor unit ground | Uncommon | ✗ Call a pro → |
When to Call a Professional
Contact a licensed HVAC technician if:
- The LED is flashing rapidly and continuously — an electrician or HVAC technician must correct the wiring polarity
- The furnace was recently installed or serviced and now shows this code
✓ Verified against manufacturer service manual — March 2026