DIY Home Improvement, Remodeling & Repair Forum

DIY Home Improvement, Remodeling & Repair Forum (
-   HVAC (
-   -   How can I tell if my condenser/compressor is not working? Lennox 10ACC−036−23 (

TGrayson 06-09-2013 11:02 PM

How can I tell if my condenser/compressor is not working? Lennox 10ACC−036−23
Hey Guys,
I haven't been here in a while, but it's good to see some familiar names!

I have a Lennox 10ACC−036−230, last night I noticed that the air coming out of the vents was a little warm & I also noticed a loud screeching sound coming from the unit outside. It also sounded like the condenser fan was not turning. So I immediately shut the system off by the thermostat. I have had problems with the fan in the past which had been resolved by replacing the capacitor and oiling the fan shaft with Zoom oil. The system has also had a slow refrigerant leak so at the start of the season (within the last month) I again oiled the fan and also recharged the system with approx. 2 lbs. of R22. I was not able to go outside to physically check the unit tonight because it was dark and it was raining quite a bit (I know waa!). I plan to check it first thing in the morning.

I am concerned that it might have over-heated the compressor since it was blowing warm air out of the return vents/registers. How can I tell if the compressor is working properly? I know how to check the fan but I don't want to replace the fan not knowing if the compressor was damaged.

Thanks for your help!

WindowsonWashington 06-10-2013 08:18 AM

Is there a power switch out by the unit?

TGrayson 06-10-2013 09:12 AM

There is a breaker box outside by the unit with a handle to pull out to shut off power to it.

TGrayson 06-10-2013 09:57 AM

Ok, I just went outside to check it out. The fan motor was able to spin freely. I oiled the fan shaft again. I had an extra capacitor so I swapped it out, it's 7.5 MFD, 440 VAC (several yrs ago a tech replaced a dual w/2 singles). I turned it on and it started right up. There is cool air coming out of the vents now but the fan motor does sound a little louder than normal & a high pitch squeal can be heard in the background noise, but nothing like it sounded last night.

I am letting it run for a little bit while keeping a close eye on it. Do you think the fan motor could be going bad? I do you an account with Grainger so I can pick up a new fan motor there for about $75 if it is absolutely necessary.

Thanks for your help!

TGrayson 06-10-2013 01:52 PM

OK, new update. It happened again. The fan stops spinning and there is a loud screeching sound and when I turn it off the screeching wines down slowly like the motor is spinning to a stop but the fan blade is not spinning, I am not sure if this has anything to do with it but both times the fan motor has stopped working is when it was raining.

The new motor that I am looking to buy is Dayton Condenser Fan Motor, 1/3 HP, 1075 rpm, 60Hz and requires a run capacitor, 7.5 MFD, 370 VAC. I have a fairly new 7.5 MFD with 440 VAC do you think I could use that one on the new motor or should I get a new cap w/new motor? Also the compressor has a separate cap on it, it's 50 MFD with 440 VAC, so I get a dual to cover both? A service tech a few years back replaced a dual with two singles (I guess b/c he didn't have a dual w/him).

I would like to buy the new motor tomorrow, Wednesday because it is going to be about 95 degrees here. So any advice would be greatly appreciated!!

Thanks again!

kok328 06-10-2013 03:31 PM

Yes, I recall this one.
It looks like we are going to have to bite the bullet and install a new compressor fan motor.
Here's a link the last years discussion:

Disconnect power, pay attention to pitch, depth and motor rotation direction before removing fan motor or blades.
Use separate new & tested good capacitors.

Good Luck

TGrayson 06-10-2013 06:39 PM

Hey thanks for remembering. The fan motor that I am purchasing from Grainger recommends a 7.5 MFD, 370 VAC but the compressor cap that is there now is 50 MFD, 440 VAC can those two work together or should I purchase 7.5 MFD, 440 for the new motor.

This is the motor I decided on:

Thanks again!

TGrayson 06-11-2013 10:27 AM

Can I connect a CAP w/ 440 vac to CAP w/ 370 vac?
Ok I ordered the new fan motor & am getting ready to go pick it up. Please see previous post for CAP details because I ordered the 7.5 mfd, 440 vac but it apparently is backordered. I would like to install a new cap with the new fan can I use the 7.5 mfd, 370 vac with the compressor cap 50 mfd, 440 vac because they are connected with a jumper? Please see pic below:

kok328 06-11-2013 10:37 AM

Use the recommended rated cap for both the blower motor & compressor.
They will be different per manufacturer and that's why I sugessted using separate caps on this repair.
You can't always go by what someone else put in there versus what is suppose to be in there.
For the new motor, it will tell you what cap rating you need. For the compressor, you may have to see what is printed on the compressor nameplate.

TGrayson 06-11-2013 10:41 AM

OK! Thanks again. I am going to pick it up right now. Like i said, they didn't have the 7.5 mfd, 440 vac anyway. I just wasn't sure if I could connect the 2 different vac's together.

All times are GMT -6. The time now is 10:41 AM.