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How to hook up new whole house fan

2149 Views 8 Replies 4 Participants Last post by  mach 1
I just mounted the whole house fan motor. I have a basic on/off switch with all romex going to the fan with one black wire, and one white wire.
My question is: Since the new motor has one red, one black, two browns for the cap, one yellow, one white, and one blue wire. The ground wire is attached from the motor housing, the screwed to the metal frame.
Which wires go where?
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Whole house fan..

There is currently just romex wiring !987 era, where the old fan was connected to. The new fan motor has seven wires.
I know black goes to black, white to white. But what happens to the red, yellow, and blue. The two browns are for the cap.
I'll get a picture later.
Whole house fan..

No insructions. Not even a basic wiring sheet.
Sounds like a multi-speed motor.

Got any information on the unit, such as brand and model #?
Whole house fan...

Thanks for the reply,
The new fan motor is from A.O Smith #754a, came with the cap POC7.5.
You are right, it is a multi-speed motor. The old motor worked like: On/off. Again, I'm looking at the decal I just found at the bottom of the box, regarding the connection diagram.
I'm lost to what goes where.
For example, the motor has a green groung wire coming out from its housing.
Then there is red, black two browns ( one brown has a white stripe on it), yellow, white, blue.
Please bare with me if I gave you too much info...
Thanks for your time,
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Grainger has specs here:

Drillspot has specs here:

Looks like a harness with quick connect terminal. If not for furnace application, probably goes with special switch that selects speeds.
2 browns on the capacitor.

White to incoming white neutral conductor.

Black, Red, Blue, and Yellow are for each of the 4 speeds. You connect your other incoming line to one of these -- depending on which speed you want it to operate at. Individually cap off the remaining wires.
Whole house fan..

Thank you to all..
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