Pressure Switch Stuck Open... Suggestions?

Old 01-14-14, 04:32 PM
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Pressure Switch Stuck Open... Suggestions?

The blinking LED on the board of my furnace is a "pressure switch stuck open" error. I have disconnected the hoses to the switch, blown air through them, and can hear the clicking in the switch when I blow air in or out. I reattached them, and the furnace is still giving me the same error code.

Any suggestions as to what I should try next?

Or, is it time to have the unit serviced by a professional?

Josh from IL
Old 01-14-14, 08:24 PM
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It's "pressure switch open." Not stuck open.

Is the draft inducer blower actually running ? (little fan where pressure switch hose connects)
Check the connection at the inducer fan. See if the little hole where the hose connects is clogged.

If that checks ok leave the make and model of your furnace.
Old 01-14-14, 08:25 PM
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reset the toggle power need to clear that LED diagnostic then restart...inducted draft motor is the first item to run when the stat calls for heat
Old 01-15-14, 01:32 AM
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The steel nipple where the rubber hose from the pressure switch connects to the induced draft fan housing is often subject to internal corrosion that will build to the point where it occludes the air passage to the switch diaphragm. Using a series of small (numbered) drill bits you can clean out this passage. This cleaning out of the air passages should be part of the normal routing maintenance on any gas-fired burner that uses a pressure switch.
Old 01-15-14, 09:14 PM
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pressure switch typically don't fail open, steel nipple where rubber hosing goes from the nipple to the press sure may be clogged, the nipple may be clogged, also check the rubber tubing for cracks.

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