Quadrafire woodstove blower intermittently working

[hotwired]

We have a Quadrafire 3400 I believe. Attached to the rear bottom is the blower which forces air up and out the top front gap. There's a little cable that comes out with a magnetized temp probe that you stick to the side of the stove so that you can set the blower on "automatic". BUT it also has a "manual" setting so you can just turn the blower on and off at will, irregardless of temperature. However, literally since the first year we've owned it, we've had no control over when it comes on or off. If I haven't used it in a while, I'll switch it on manual and voila, it blows like crazy. Then suddenly the next time it won't. And this is on the "manual" setting. No rhyme or reason. (This is why I posted another thread asking for fan recommendations). I wiggled the cable six ways from Sunday to see if there was a short, but that didn't work. I just don't understand it. Over 13 years and there's not a single thing I can deduce. Absolutely no rhyme reason or pattern. Do you folks have any thoughts or any experiments I can try? (As I'm writing this, I'm wondering if holding an open flame to the aforementioned sensor might eliminate something...i.e. if I over heat that sensor, and it always comes on when I do that, then maybe I short the wires, and only use it on manual??)

 

[begreen]

This might be a faulty rheostat on the speed control. When set to manual, the magnetic probe is bypassed. Try rotating the speed control knob from high to low several times to see if that wakes up the blower.