Perfect time for the heater to die

[aviator41]

So, I come home this evening to hear the condensor on our heat pump humming like mad and the fan not running. A quick check with the voltmeter and it looks like the run capacitor on the fan motor has died.

Hope Locke supply has one tomorrow. it's going to be a cold night.... brrr...

 

[dennishoddy]

What did the OG&E tech find out today? Probably related

 

[aviator41]

Haven't heard back from them yet. they are supposedly monitoring the home for a week. I agree, it's most likely related.

 

[tyromeo55]

If it is just the fan motor run cap then there is a way to get it going in a pinch.


Pull the disconnect and wire the fan motor to run all the time ( bypass the contactor for the fan only ). Then power up the unit and then with a stick quickly push start the fan. It will stay running and the compressor will cycle with the thermostat

 

[aviator41]

This particular unit uses a start/run capacitor and won't operate at all with the capacitor bypassed. I did manage to get it spinning, but the capacitor is so shot it can't keep the motor going. I know that capacitor doesn't actually keep the motor running, but it helps maintain the magnetic fields in the coils to keep the fan going.

The fan is free spinning without the power shut off, so I think the motor is okay. The capacitor is apparently a service capacitor that has a number of tabs on the top of it, allowing the capacitor to be used in several different size units. Apparently the service tech was supposed to come back out and put a standard cap back in place, but never did.

I still think this is yet another victim of the power problems I'm having.

 

[tyromeo55]

Man, if it wasn't for bad luck you wouldn't have much luck at all. I'd be surprised if the fan motor had a start and run cap and only a small run cap like 5 mfd. if that is true then it will push start with a stick if it is good. Spinning freely only means that the rotor is free and the bearings are good. Did you happen to ohm it out? Hopefully it is not fried too. I keep quite a few caps at the office. If for some odd reason you come to tulsa I'd give ya one

 

[aviator41]

Well, it turns out the motor was toast too. After trying a start/run capacitor (40mfd/5mfd, 440v) with no luck, I went ahead and pulled the top of the unit so I could feel the fan blades turning. They were very stiff. Looks like the motor shelled it's bearing at some point as the bottom of the motor is greasy and the shaft can't be turned by hand without the fan on it. turning those blades with a stick from the outside had me fooled!

Luckily Locke Supply in Edmond had a replacement for $150. The cap was $40. All told, A sub $200 fix to get the heat pump back up and running. I have OG&E recording power to the house at the moment and got a good lead from BikerHT for an electrician. Now I just gotta call him and get him out here once the bad weather clears out. At this point, I am comfortable saying the motor was physically worn out and was most likely not a victim of bad power.

Thanks for all the help guys. sometimes you just can't win for losing. I'm thankful that I have the technical knowledge and tools to work on stuff like this myself as well as a the money needed to get the parts. The Locke Supply guy said This could have easily been a $700+ service call for someone that couldn't do the work themselves. I told him that I was surprised that he would sell parts to a non-HVAC tech (they have a big yellow sign that says they don't do that), he smirked and said if it hadn't been snowing outside, and I didn't appear to know what I was doing, he'd not have made the sale.

Finally, a little luck!

 

[Okie4570]

Glad you got it going, the next few nights are supposed to be nippy...........the days are too for that matter!