Starter Capacitor - Air Conditioner

Thanks to dougrainer, daveinet, diplomatdon and all others....great advice. I'll check the price from P.P.L. I called a friend in the Hyvac business who had a couple of starter capacitators on his desk, but needed the number. He's not cheap though.

I have to park my motorhome about 7 miles away at my son's parking lot because of our subdivision's by-laws, which makes it rather difficult to work on, so it will be next week before I can get on top to check it and get the model number. I will take a 2x4 as back-up.:D

I don't hear any compressor noise, like it's trying to start, from the inside. It's just that only the fan will run. Will let you know the outcome after I check it.

Thanks,
Hapytracks

Last summer one of my AC's wouldn't run, just hummed. It only took 15-20 minutes to swap starting capacitors with the working unit to determine whether that was the problem. Sadly it wasn't.

Did you smell burning rubber or the smell of burning wiring insulation?
If you did it is as others have said the capacitor. It will get very hot trying to start the motor but the energy is heating the capacitor and not getting to the motor.

dougrainer wrote:

Dog Trainer wrote:
It could be capacitor or the same thing can happen if it is low or out or freon Or what ever juice they use these days.

RV Roof AC units have no low Freon switches. Doug

How well I know I just changed my rear air after losing the freon. I did put a hard start capacitor in it and it did start the compressor but no cooling. So a new A/C. Yhe point I was making is that a loss of freon will cause the compressor not to start.

Happytracks....Get the model number off of your unit and go to PPL Parts. It can be a little difficult to surf their parts website, but they have a listing for your A/C by model number. It will open up a page that shows the various parts for your A/C unit along with photos. I had another issue, but replaced my start capacitor since I was ordering parts. I found DuoTherm uses a hose clamp to support the capacitor. Mine was squeezed so tight that it distorted the capacitor.

This link is to the actual A/C parts page DuoTherm Parts

When it comes to repairs like this, I'm willing to spend a few dollars to try a part before spending hundreds of dollars on a tech.

Visual sign of being bad are swollen or burst. Typically the stink pretty bad as well. If the cap is OK, have someone turn the unit on. At the point they are turning it on, give the compressor a good wack with a rubber mallet, or a 2X4. It may take off and run. Sometimes after they sit for a long time, the compressor will stick. Wacking it when it is trying to start may break it loose.

Happytracks wrote:
Question: My rear air unit will not come on with generator power or outside 120. The fan works. Could this be a starter capacitor? Is the fan separate from air unit wiring?

Front unit works fine. I have a "Comfort Control Center" Duo-Therm.

Thanks,
Happytracks

ALL the wiring is the same part of the unit. You can check for a defective capacitor by doing a visual inspection of the capacitors on top of the unit. MOST Compressor start capacitors if bad will show signs of damage. You need to be on top the unit and have someone start the unit in lo fan COOL mode, and wait 3 minutes. See if the compressor tries to start or lugs down. Then kicks out. There is a 2 to 3 minute time delay from turning on the AC before the compressor starts and the same delay between compressor start attempts. Doug

Dog Trainer wrote:
It could be capacitor or the same thing can happen if it is low or out or freon Or what ever juice they use these days.

RV Roof AC units have no low Freon switches. Doug

It could be capacitor or the same thing can happen if it is low or out or freon Or what ever juice they use these days.

I also had to replace mine, it was a dual (fan & compressor) 15/50 MF. I also carry a spare. It was just under $20 bucks. I hope this helps, Bill