Need Electrical Help!!!

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Hooking up a blower motor on my furnace. All my wires are black except for a green one. I need to know what ones are> High speed/Low speed/Common. Two of the black wires are within a wide piece of insulation along with the green wire. Another black wire is just by itself.
 
You sure it's a two speed? Wiring diagram on label? If a 115v two speed motor, it would have to have 4 wires. 1=common, 2=high speed, 3=low speed, 4=ground. That's on a non-PSC motor.
Check your wiring diagram. It should be labeled.
 
It has 4 wires- 2 blacks and a green together and a single black.
how will I know if I have it hooked up right.
 
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Is there a label with a brand name and model number? I purchase such motors for Lennox and every one of them has a label with enough information to find the motor online.
 
I find that hard to believe. No numbers, no diagram?

Take a picture, maybe we can help you figure it out.
 
Maybe Grainger has a tech service line. Your motor must be a specific oem replacement rather than a universal. Where did you get your motor?
 
Theres a diagram but what wires from my furnace are High speed- Low speed -common? Theres 3 black and one green
 
New motor same as old? I bet the furnace schematic is no longer there. Probably a common leg connection rail, maybe a peanut relay for speed control? I can only guess. Good luck.
 
Originally Posted By: Warstud
Theres a diagram but what wires from my furnace are High speed- Low speed -common? Theres 3 black and one green

If still running your old 2-speed motor, check it's label for the wiring and follow the wires to the furnace then mark before removing. Good night
 
Tried running the motor with belt off....ran great. As soon as I hook it up to the fan the motor starts smoking. Maybe the fan isn't spinning as freely as it should IDK.
 
OK. Let us review all the facts.

1) Brand new motor runs standalone
2) Once the belt is hooked up to the fan, motor starts smoking. (incidentally old motor behavior was similar)
3) Fan runs fine when turned by hand.

If you can confirm those facts, then the bearing/bushing of the fan is failing when you put the belt on. Two things can do it. Either bearing/bushing has too much play or the belt is way too tight.
 
Update:

Well I decided to throw in the towel blanket and have an HVAC guy come out. He said the blower fan doesn't spin as freely as it should and that the bearings are probably shot. Should I replace them myself or just pay someone to do it. What is this job on the difficulty scale? 10 being easy - 1 being hard.
 
What did the technician quote for the repair cost? I'd be tired of living in the cold since it's zero outside now. Get er done, this has been draggin on for awhile. I saw the other thread about this.
 
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