A thermistor, is similar to a thermostat, but has a specific resistance, usually based on temperature, and has a wide variance in readings which inputs to the control, which is looking foe the input, to determine what the contol needs to do.

Before you go too far, You should probably check the Magnetron Thermostat, for a closed circuit, In most cases that thermostat is a "one shot" like a fuse and will shut down power if or when it opens.

As a last resort, you can "bypass" the component using a "jumper" wire, but that is a last resort and could be somewhat dangerous, if you do it wrong.

Hope that helps,

:) :) :)