Amana AMSS920803BN Error Code 2 Flashes: Pressure Switch Stuck Closed
What Does Code 2 Flashes Mean?
Two flashes on the Amana AMSS920803BN indicate the pressure switch circuit is closed when it should be open. The pressure switch is a safety interlock that must stay open at rest and close only after the induced-draft blower proves adequate venting. If the Integrated Control Module sees the circuit already closed before the inducer even runs, it refuses to advance the ignition sequence — it can no longer trust the switch to confirm real draft.
Because this is a single-stage furnace there is a single pressure switch (unlike two-stage models that use a switch for each fire rate), so the diagnosis is focused. The most likely cause is a switch whose contacts have physically stuck closed after thousands of cycles; less often, a short in the switch wiring makes the board read a closed circuit that is not really there.
This code is the mirror image of three flashes (code-3), where the inducer runs but the switch fails to close. Together the two codes cover both failure directions of the same pressure switch, which is why a technician confirms which way the switch is misbehaving before replacing it.
What You'll Notice
- The furnace does nothing on a call for heat, and the inducer may never start
- The single diagnostic LED blinks twice, pauses, and repeats
- No draft sound and no ignition sequence
- No heat despite the thermostat calling for it
- The code may appear right after a pressure switch or inducer part was replaced
Common Causes
| Cause | Likelihood | DIY? |
|---|---|---|
| Pressure switch contacts stuck closed | Most common | ✗ Call a pro → |
| Short in pressure switch wiring | Uncommon | ✗ Call a pro → |
How This Is Diagnosed
A technician confirms the switch is genuinely closed at rest by checking continuity with the inducer off, then inspects for a mechanically stuck contact. They also check the switch harness for a short that would look like a closed circuit to the board. If the switch is stuck or its wiring is shorted, the correct replacement part is installed; the control module is only suspected after the switch and wiring have been cleared.
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 furnace will not start and the LED shows two flashes
- The inducer never energizes on a call for heat
- The code appeared right after a pressure switch or inducer motor was serviced
- The furnace alternates between two flashes and three flashes on different attempts
Frequently Asked Questions
What is the pressure switch actually checking?
It confirms the inducer is moving combustion gases before the burners light. Two flashes mean the board read the switch as closed too early, so it refuses to fire as a safety measure.
Can I jump or bypass the pressure switch to get heat?
No. Jumping the switch defeats a safety interlock that prevents firing without proven venting and can allow dangerous operation. The switch should be tested and replaced by a technician.
How is two flashes different from three flashes?
Two flashes mean the switch is stuck closed before the inducer runs; three flashes mean the inducer is running but the switch will not close. They are opposite failures of the same component.
Sources
✓ Verified against manufacturer service manual — March 2026