Ok guys here is the deal, recently my heat pump motor decided to seize up making my house smell like nice burnt electronics.. So I replaced it with a new motor, making sure all of the dimensions were exact. I replaced the wiring exactly as it was, basically white is common, red is low, blue medium, black is high, both browns are for the capacitor, and yellow/green is ground. The problem is that when I turn the system on, it starts up and is nice an powerful for about a minute and 20-30 seconds then it shuts itself off. I went back into my attic and the motor was very hot from the short time of it being on. Anyone have any ideas what could be causing this? I also replaced the capacitor when I replaced the motor, and the wiring in my unit only plugs into the common, and number 3 and 4 plug, leaving the 1 and 4 open (above the wires show a sticker with common, hi, med, and low, so not sure where the other plug should be...) Any help would be greatly appreciated!!!
Did you check your voltage applied to the motor? What else is in the circuit? It sounds like whatever happened to your last motor is still the route cause if the new motor is heating up. Good thing your new motor shuts itself off before releasing the smoke.
1) Is the new motor the correct voltage? Usually, 240 applied to a 120 motor will burn up the motor in about 10 seconds, but check anyway.
2) Is the capacitor good? and the correct rating? The two brown leads go to the capacitor, it doesn't matter which lead goes to which terminal.
3) There could be a problem in the control circuitry that applies voltage to two speeds at the same time. This will cause exactly the symptoms you describe. Remove and insulate all but one of the speed wires and see if it runs longer.