Help BK fans not turning on

I have an King and have not had a problem til tonight the fans wont turn on checked outlet it works there is power at wall outlet. What else should I check?? Makes a big difference!!

There is a snap disk on the RH (looking at the stove) blower, the one with the rheostat on it. You have to remove the blower to get at it. That's where I would start.

Are you starting a cold stove? Does take a while to heat up. If so, and there is much ash built up, clean it out of that corner to let the steel heat up faster.

should fire right up on manual.

My fans have a shut off switch when the stove is cold.
After a new fire & the stove warms up they should start working. Sometimes 30 minutes or so to heat up the switch.
jeff-t described the sw location.

If not working after an hour, you may have a bad "cold shut off switch"
Should be in the book, for the fan assembly.

The modern ultra does not have a manual/auto setting. It is all snap disk controlled, you can shut it off or choose the speed. Never can you force it on. My fans still work and don't get much use so I can't help other than to advise that you be sure that the fan is on by getting the stove fully up to temp and running the knob back and forth fully.