Wiring a Replacement HVAC Blower Motor for an American Standard Heat Pump Air Handler

Question

I undertook what I thought would be a straight forward task.... Needless to say I have run into an issue that I need some help with.

The replacement motor is a century 4ka35 motor with the following wires. I only need the high speed setting as the air handler is older and not setup for multiple speeds even though the old motor was multispeed.

Brown and Brown/white to the capacitor, Yellow to L1, Black(hi speed) Blue (med Speed) Red (lo Speed) to L2

I have the brown wires connected to the the capacitor, the black wire connected to the rd/3 wire shown in the diagram (this wire was connected to the hi speed terminal on the old motor) and the motor does not seem to get up to speed. Do I need to connect the l1 wire to something, if so what as I can't find it on the diagram.

air handler (Model American Standard/Train TWE036C140B0) wiring diagram

Answer 1

That is a horrible wiring diagram but basically the the black wires on the air handler are L1 and the red are L2 (or vise versa ). The yellow wire from the motor would connect to the black (L1) air handler wire and the black (hi) wire from the motor would connect to the red wire (L2) from the air handler. The two brown wires from the motor go to the capacitor and the remaining speed tap wires (blue and red) get caped individually. You should check that the new motor is indeed 230 volts. Some are dual voltage and need to be set up for 230v. Also make sure that the microfarad rating on the capacitor and the motor match.