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CMPE075U2 Ducane Forced-Air gas furnace shutting down prematurely


Premium Member
Jun 22, 2017
Model Number
-major brand-
6-10 years
Hi All,

HVAC newbie, so bear with me.

My garage is heated with a Ducane CMPE075U2 forced-air gas furnace. I've always (5+ years) had it set to a minimum temp of 45 degrees, which I've already been told was way too low!

Anyhow, it stopped worked recently so I thought there was maybe some ice in the system, as the condensate trap suffered some ice build-up years ago when we accidentally turned the furnace off in the middle of winter.

After removing and warming up the condensate trap and draining it of any water, I re-attached it, and the furnace worked fine...except only for 3 minutes, nowhere near to the 72 degrees I wanted it to heat to. If i turned the system off and back on again, it would work for another 2-3 degree increase, then turns itself off again.

Now, it won't turn on at all. I feel there's no water draining through the condensate trap, but that could just be because it's only on for a few minutes before it shuts down. Each time I remove the trap, there's a bit of water in it. No reason to think the drain hose is clogged or anything either.

Also, no error lights flashing when it turns off.

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