I am trying to help my mom out. My dad who is now in a nursing home installed a Broam attic fan and the motor has stopped working. I turned off the breaker and went on the roof and took out the motor cutting the black, white, green wires. I now have a new motor to install, my dad told me many years ago he had a 2 speed motor so he used a 3 way switch in the hallway. The switch when in the middle is off, up is fast speed, down is slow speed. Well the motor I removed only had the black, white, green wires (no red wire) so I guess he had replaced the motor in the past to a 1 speed motor.
When I go into the attic I see the Broam thermostat that has the wires from the switch in the hallway. The hallway switch has a black, white, ground, and a red which has me confused. I understand the black from the hallway switch goes into the input tab of the thermostat which has a BLUE quick connect then the black from the fan motor goes to the output tab on the thermostat with a quick connect. The white from the motor goes to the white from the switch in the hall. What do I do with the red wire??? The breaker does supply power to some other switches in the house also.
I thought possibly my dad wired it so the black from the hallway switch goes into the blue quick connect that is going into the input on the thermostat in the attic, and the black from the motor goes to the output side of the thermostat and so does the red with a wire nut. The white from the switch and the white from the motor wire nut together and the 2 grounds are grounded. In the spring when the fan motor worked I could turn the switch up or down and the fan would come on but the motor only had a black, white, green wires no red. If he did it this way when the switch is up the power would go to the motor from the black wire, the switch down the power would go to the motor by the red wire that is nutted to the output side of the thermostat with the black, and the black from the motor. This would make it possible to bypass the attic thermostat and turn on the fan any time.
I have looked at the Broam wiring diagram but am still confused because the switch works the 1 speed fan when up or down.