When the power source is present at the wall switch box the a 3 wire cable would be installed from.
Exhaust fan and light switch wiring.
Wiring a fan and light to a single switch in this wiring the source is at the switch and 3 wire cable runs from there to the fan and light.
This video with new full edited instruction for those who asked.
Connect a light and a fan to a new switch.
Twist the ground wires together and connect them to the green ground screw on the switch.
Pull electrical cable between the fan light and the switch.
Locate the switch cable which must be glued through the top or side of the box that serves the fan or the light.
Connect the black fan cable together with the black light wire and the black switch wire and cover them.
If you choose to do this.
There is a black wire red one white one and the ground that is in the box.
The wires are in the same box.
Junction box wiring for the switch the box these wires came out of had a 3 wire w ground coming in from the other switch.
Inside the box you ll need to separate the wires to see which feed the fan and which feed the light.
If the fan has a pair of black wires and a pair of white ones you can wire the light separately from the fan.
The source neutral and ground are spliced through to the fan location.
The source hot wire is spliced to the black fan wire to hardwire it directly to the circuit and to a pigtail connecting the switch.
Wiring an exhaust fan with a light fixture using a combo switch as long as the bathroom exhaust fan and light have separate wire leads or connections in the exhaust fan junction box.
Splice the white wires together and cap them.
Once your fan is free position it so that you can easily access the connection box.
How to wire a bath exhaust fan and light removing existing wiring i removed the 2 wire with ground from the switch to fixture and replaced it with a 3 wire with.
The light switch has a black wire hooked to it and the black wire that goes to the fan and the light.
Using wire strippers peel an inch of insulation from the end of the black and white wires.
Connect the black wire from the fan to the bottom terminal of the switch and the live circuit wire to the top terminal.
The fan switch has the ground wire the red one and the white one hook to it.
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