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1980s intertherm furnace cycling on and off

nick1nick1 Member Posts: 2
I have a 1980s home with an intertherm propane furnace in it, the blower cycles on and off continuously while the burner is still on.
I replaced the one button style limit switch already and that did not help, I am left to believe it is the remaining limit/fan combo switch which is no longer made unfortunately. I tracked down the best recommended replacement part which is a camstat FAL3C-05TD-120-A. This part has only 4 spots for wires, and the old switch has 5 wires coming from it. 40tn33113 is the old part number, and I cant seem to get photos to load. I am a mechanical engineer, but cannot figure this out and have already had the only service guy out here that comes up this way. I live in the mountains of CO, nobody serves my area. We are getting cold up here, so any help is very appreciated.


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