unlike UL, CSA stipulates that any AC motors must come with additional form of protection from overheating (which the winding insulation may break down causing shorts--- fire). An additional thermal fuse must be included into all AC motors, so that when the coil overheats, it would burn out the thermal fuse to protect from burning.
If your motors are CSA rated, maybe there's the additional thermal fuse within that is burned open circuit. Check to see if that's the case.
Lastly: that's a thermal fuse, not an MOV, for MOV doesn't open circuit to protect the device from overheating...MOV only absorbs power surge (spikes) and dissipates it into form of heat.
More on the subject of MOV if interested.
Quest
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