Insert the end of the 12 2 wire into the fans junction box.
How to wire attic fan timer.
Strip away about 6 inches of outer insulation and 1 2 inch of individual insulation from the end of each wire.
Then you could parallel connect the connections for hot l1 and low speed to the timer black and red timer wires respectively.
You would need to run an additional neutral wire to the switch box so the timer would have a neutral connection.
Attach the black wire to the top brass screw on the switch.
At the switch connect the white wires together.
Use wire nuts to connect.
Attic fan switch and timer.
A how to demonstration of wiring your xxfirestat or power attic vent thermostat.
Z7pt3 electrical would this the correct way to timer switch whole.
Attic fan switch and timer.
Then screw on the switch cover and attach the timer plate and knob.
Each package will have directions on what is required which wire goes where.
Place the switch cover and test.
Adjust the toggle switch for the light and the shaft for the timer accordingly to make them line up with the switch cover.
In our case we have three stranded wires that one should twist gently in a clockwise fashion.
The attic fan wiring is now complete.
Turn on the power and test your work.
Then you could turn on the low speed with the switch or the timer.
Depending on your timer you may either have to use wire nuts back stab side stab or attach it via side screws.
December 24 2018 april 12 2020.
Connect the copper wires together.
Connect the black and white fan wires to the black and white switch wires.
Install wire to the fan from the switch box.
Manual transfer switch wiring diagram.
Diagram for wiring 2 speed switch timer for attic fan.