MEDIUM URGENCY

Nordyne 4 Flashes - Pressure Switch Stuck Closed

4 flashes

Pressure switch stuck closed when inducer is off.

Brand: Nordyne (Also covers Frigidaire, Maytag, Westinghouse, Tappan, Gibson, Intertherm, NuTone, Miller, Broan) | Equipment: Gas Furnace

What This Code Means

4 flashes on Nordyne-family furnaces means the pressure switch shows closed contacts when the inducer isn't running. Switch should be open at rest.

Most common

What: Contacts welded or jammed.

How to check: Test continuity with inducer off.

Fix: Replace switch.

Shop parts

Less common

What: Board misreads switch state.

How to check: Test switch independently.

Fix: Replace board.

Shop parts

DIY fix?

Yes - pressure switch is straightforward replacement.

Cost?

Switch $25-60.

Same on Frigidaire/Maytag?

Yes.