I am replacing a bathroom exhaust fan with light. There is 1 switch to control both fan and light. New unit has a white, black, and blue wire. Main wire in ceiling has a white, black, and copper ground. What do I do with the blue wire? I tried connecting with the black wires; light came on but fan did not. Instructions included with fan state to connect blue wire to red wire (shows going to switch box). There is no red wire present.

  • What do you mean "main wire".? Is there only one cable in the box, or is there more than one? (The thing with multiple wires in a sheath is called a "cable".) Commented Oct 14, 2020 at 1:04
  • should hire an electrician if you dont know the difference betweeen ground, hot and neutral. Commented Apr 6 at 22:57
  • Doesn't the product come with a manual?
    – liaifat85
    Commented Apr 7 at 20:53

1 Answer 1


IF YOU ARE IN THE US... the Black and blue wires are the HOTS for the Light and Fan This allows for them to be controlled separately if desired. If you want them both to go on with the switch, they both connect to the Black Hot wire (which should already be the switched one from your light switch). White goes to white and the copper ground wire should have a copper screw on the base of the new fan to tie it under to provide a ground. Colors are different in different countries, so please provide that info and the model of light or some pictures.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.