York Diamond 90 not firing up

Old 02-10-14, 10:06 AM
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York Diamond 90 not firing up

Hello. I went over to my vacant rental this weekend to blow off the driveway and check on the house. Upon entering, it was chilly. The thermostat was at 33 and I can hear the furnace inducer motor making the furnace sound really loud with no production.
I turned off the furnace and went down to investigate. When I fired it back up, I was getting 3 flashes for the error code. I shut it off and went back this morning in daylight. I fired it back up and heard some rattling in the PVC pipes, then it stopped. The inducer doesn't sound as loud but am still not getting it to fire or click over or anything, still with a 3 flash code.
I'm not very versed with hvac but am inclined to try anything.
Can you help ?
Old 02-10-14, 04:46 PM
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searching on [York Diamond 90 code 3] yeilds many results
Old 02-10-14, 06:21 PM
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On many furnaces a 3 code indicates a pressure switch failing to close. Check the inside of the blower door for a sticker with the key to the codes.

If you heard something in the vent pipes, I'd start by making sure they are clear of any debris.

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