Nutone bathroom exhaust fan

I just install Nutone 765HFL ceiling bathroom exhaust fan. It has 3 separate switches to control light, exhaust fan and heater. Two romex going from from switch to the machine. Both black and white wire inside 1 of the romex are hot. Another romex has 1 hot and 1 neutral. Both light and exhaust fan works fine.

The heater is not working. When I first turn it on for the first time, I saw heating element glowing but heat fan is not running. I turned off the heater right away, I worry it may overheat. Second time, I turn it on the heating fan is running but heating element is not heating up. Now the the heating fan runs but heat element does not heat up.

Any ideas what is wrong with the machine?

 

First problem is that is not code compliant. Both the neutral and hot must be in the same cable. While that is not your problem it must be corrected either by adding a third 2-wire cable or replacing one with a 3-wire cable (better) or ENT with individual wires.

As to your problem does power come in at the switch? Tell us how you wired it at the switch. When you decide which code compliant wiring method you are going to use we can further advice on connections. ENT is probably best because the device connection boxes are usually small and ENT requires only 4 wires plus ground.

 

I know it is not code compliant. Somebody else wire from the switch to the machine years ago. I am just replacing the old machines with new machine. I just realized I posted this message in wrong section. I will post the same message in Ducting, Air Circulation and Ventilation Systems section. Thanks you.

 

No, you are in the correct section.

 

If this unit has a heater it will require its own circuit.

 

Did the one you replaced have a heater? What is the heater watts. What else is on this circuit. Again tell us your wiring at the switch.