I am looking for a manual for this old fireplace. The problem I have is the squirrel fan does not kick in or out when it is suppose to. Maybe I need a switch? Thermal coupler?
If you apply 120V directly to the motor and it works you likely have a faulty thermoswitch. It's wired in series with the fan and is usually mounted high on the back or sides of the fireplace.
It will have a temperature ON / OFF rating and you can replace it with any universal part.
Have you confirmed that the fan does work? It's often the bearings that dry out first and the fan seizes up. Depending on the setup, the thermal disc can have a fairly long delay to come on and off. Additional decorative accessories (such as porcelain panels/fake bricks) can slow down the rate of heat transfer to the thermal disc.
You can call CFM for the manual.Usually it takes while to kick up the fan.The home owner would able to tell the fan was operational.good luck.