110 degrees F. (3/4 inch disk shape)
This can be added to any of the furnace units that do not come with this switch.
Simply place it in line with the power, mount the switch on the furnace housing / jacket so that will allow the fan to come on as the fireplace gets hotter and will also turn it off as it cools down.Do not mount directly on fire box.At the risk of an unpaid advertisment, I would suggest the 24 hour cure Araldite - NOT the 5-Minute one. Clamp the switch to the surface until the adhesive has cured - this can be done easily with painters' masking tape for awkward shapes.Use the adhesive sparingly - some of these switches are open at the contact face, and if epoxy enters the internals of the switch it may ruin it.

This switch reacts only to thermal affects and requires no electricity to operate. Normally open switch closes at rated temperature sending power to fan. Can be used in conjunction with fan speed controllers for maximum versatility. Swivel bracket allows switch to be mounted to any flat surface. These are for the power transformer, and one for each heatsink. The incoming mains (after the power switch and fuse) is routed as shown through each of the thermal switches, and finally to the transformer primary.
Should any of the protected items exceed the switch temperature, the amplifier will be turned off. It will turn back on again when it cools enough for the switch to reset. In the case of a fault, the amp will turn off and back on again until the problem is rectified, but at least there is protection.
Normally open circuit
Switch closes at rated temperature
Max load 8.5A @ 12 VDC
Voltage Rating 250 VAC