Amana AMSS920803BN Error Code Continuous/Rapid Flash: Reversed Polarity
What Does Code Continuous/Rapid Flash Mean?
A rapid, continuous flash on the Amana AMSS920803BN means the Integrated Control Module has detected reversed polarity in the 115-volt or 24-volt supply. The board needs correct polarity to run and to sense flame reliably, so it refuses to operate until the wiring is corrected.
Reversed polarity means the hot (line) and neutral conductors are connected to the wrong terminals, or the transformer's orange and gray leads are swapped on the board. Because of that, this code almost always appears right after installation, a control-board replacement, an outlet change, or other electrical work — it is a wiring mistake, not a worn-out part. A poor unit ground can trigger the same rapid flash in less common cases.
It helps to distinguish this pattern from the other two power-related indications on the same LED. A completely dark LED (code-off) means the board has no power at all, and a steady on LED (code-on) is normal operation. The rapid continuous flash sits between them: the board is powered but sees the supply wired backward. At a quick glance the fast flash can look almost steady, so it is worth watching the LED closely. Correcting it is 115-volt wiring work that must be done with the power off.
What You'll Notice
- The single diagnostic LED flashes rapidly and continuously instead of glowing steady
- The furnace will not start on a call for heat
- The problem began right after installation, an outlet change, or other electrical work
- Other furnace functions appear dead even though power is clearly present
- The rapid flash persists after the furnace is switched off and back on
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 → |
How This Is Diagnosed
A technician verifies line polarity at the furnace with a meter, confirming that hot and neutral are not reversed at the receptacle or junction box feeding the unit. They inspect the transformer's orange and gray leads on the control module for a swap and confirm the unit has a proper ground. Any miswiring is corrected with the power turned off, then the LED is rechecked for a steady on indication.
When to Call a Professional
This code involves components that are not homeowner-serviceable, so have a licensed HVAC technician diagnose and repair it. Keep in mind:
- The LED flashes rapidly and continuously and the furnace will not run
- The furnace was just installed or recently had electrical work done
- You suspect an outlet or junction box near the furnace is miswired
- The rapid flashing continues after power is cycled
Frequently Asked Questions
What does reversed polarity mean?
The hot and neutral wires are swapped somewhere in the furnace's power supply. The control board detects this and refuses to run on it for safety and reliable flame sensing.
Can I fix reversed polarity myself?
No. This is 115-volt wiring work that should be corrected by a licensed electrician or HVAC technician with the power turned off, since working on energized wiring is a shock hazard.
Why did this start right after an outlet was replaced?
Reversed polarity commonly results from hot and neutral being connected backward during electrical work, which is exactly what this rapid-flash code detects.
Sources
✓ Verified against manufacturer service manual — March 2026