If the wires are buried in attic insulation pass over light fixtures or worst of all are arranged in tight bundles they get even hotter than if they re out in the open air.
Attic wiring red hot.
Use the hammer and staples to secure the cable to the joists at 12 inch intervals.
Convection is the characteristic that makes hot air rise and cool air sink and it is at this point where a good ventilation system comes into play.
In order for the light to be controlled by its own switch the wiring between the switch and the fan unit needs a fourth wire a red wire to carry power to the light kit.
Use wire nuts to connect.
Staple the cable within 8 inches of both the attic light box and the thermostat box.
Once you are running the wire feed both ends of the wire through their corresponding holes and climb down from the attic.
Turn the plastic wire nuts also called wire caps onto the ends of the wires.
Strip away about 6 inches of outer insulation and 1 2 inch of individual insulation from the end of each wire.
Wire nuts that are too big will not sufficiently grip the wire and will fall off.
Leave enough cable at each end to work with.
Insert the end of the 12 2 wire into the fans junction box.
Once the air in the attic has become hot another thermodynamic process called convection occurs.
Turn the wire nut clockwise.
Wire nuts that are too small may initially feel like they are on the wire but they too may fall off.
Run nm cable from the attic fan thermostat to the attic light.
Connect the green wire to your household ground wire copper bare wire.
Connect your white wires together and secure with wire nut.
There should be no excess wire or ends left in the attic.