Furnace Constantly Shuts Off

[chrissjohnso]

Just bought our first TT. An 18 foot Mavric that was about 9 months used. The only issue the previous owner told me they had was that after the furnace runs for about 5 minutes it shuts off, until it cools down and then starts up. He claimed that it is a common problem and that it is most likely something like a spider web or other debris that mess up the sensor. I confirmed that the issue happens like he stated. Was wondering if others had similar issue and what did they do to solve it. Trying to avoid a costly trip to the service center for something I might be able to easily fix.

Regards,
Chris

[wa8yxm]

There are different reasons why it might act like that depending on the control system.

However if not enough air flows, Even though it's enough to trip the sail switch, This can be due to obstructions IN the flues (very common, dirt collects there) or due to stuff on top of a register (I'm still trying to educate my wife) the unit will over heat, and shut off, then cool down exactly as you describe.

A defective Overheat safety stat can do it too.

There may be other causes as well. If it's running at least 5 minutes before shutting down I do not ***THINK**** it is the control board (my problem is the control board, it runs for seven seconds as I recall)