The fan control is not technically needed. You could use a simple switch rated at the correct amperage. The issue is having speed control. The fan control is needed for that. The other issue is that there is a reason its getting hot. I'd try the new switch to see if that shows the same symptoms. The controller is probably the weakest link in the system so it would get hot 1st. If you remove it without finding the overheat problem you could overheat the power cord. A fan control without an on/off function may have used as a safeguard. In that instance the disk controls the on/off. That would insure that the blower is running when the stove is hot to prevent overheating the stove.