Exhaust fan will not turn off

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New Member
Dec 2, 2022
Hi everyone,

First time posting here, after many hours of reading threads. I have a quadrature contour FS in my basement which has recently started to run the exhaust fan at all times. Regardless of the operation of the stove, or demand call from the thermostat, the exhaust fan is on.

I have checked all of the thermo switches (all working), check wiring (all good), cleaned the entire unit, tested the vacuum switch (working and not clogged), and replaced the controller. I'm a maintenance electrician, so i know what I'm doing when it comes to checking this stuff out. I just can't seem to figure this out! Any suggestions?

The unit works completely fine otherwise.


Minister of Fire
Nov 17, 2019
Long Island NY
I think you'll get more response if this is moved to the pellet stove forum. @begreen?