Duo-therm rooftop air tripping breaker

[jimzz2001]

Our Front Duo-therm rooftop a/c unit (model # 600015-001, 13,500 BTU) is tripping the breaker.

I went up top and took off the shroud. fins and unit look clean, no build up. I had dw reset the breaker while I watched the a/c operate. fan comes on and after a minute or so the compressor kicks in but it seems labored.

After running a few minutes a box on the passenger side of the unit started "Cycling" kind of chugging. Not sure what this box is called

It says ESSEX 8435 128146-2844p. A google search of that showed nothing.

after the chugging the compressor stops but the fan keeps blowing. after a couple minutes the compresser kicks back in, somewhat labored again.

this cycle continues until after a few times it trips the breaker.

What should my next step be?

This is plugged into A/c with 30 amp service

thanks for any replies.

[RJay]

What is your shore power voltage?

[jimzz2001]

Quote:

Originally Posted by RJay What is your shore power voltage?

I'm not sure, and not sure where or how to test. I might add when the rear a/c unit is running it operates fine on it's own. So I am thinking current is fine.
THe front a/c is acting up when nothing else is operating

[squeak]

had the same problem I switched wires to a different breaker to see if ie was the ac or breaker

[rvjimmy]

I guess I don't know what breaker is blowing is it in the MH or on the service pole. I also don't know if you have 2 units because you can't run both on 30 amps. Other than that I'm confused as you.

[jimzz2001]

Quote:

Originally Posted by rvjimmy I guess I don't know what breaker is blowing is it in the MH or on the service pole. I also don't know if you have 2 units because you can't run both on 30 amps. Other than that I'm confused as you.

its the Motorhome breaker tripping. We do have 2 units but we are only operating this one. Other is located in the rear bedroom and is turned off, while testing this one.

We are planning a long trip in a couple weeks and are trying to make it as problem free as possible

[hometool]

i would be looking at the run capisator it may be bad causing high current draw either that or the compressor has failed. i would try swaping the run cap from the unit that wks ok lee

[D&J]

The box on the side of the compressor is the current overload. It sounds to me that you either have a start cap staying in the circuit because of a bad relay or a weak run cap. I would almost bet it's a bad run cap by what you are describing, I would replace it first and then the start cap and relay. If that doesn't fix it the compressor is bad.

Denny

[jimzz2001]

Quote:

Originally Posted by hometool i would be looking at the run capisator it may be bad causing high current draw either that or the compressor has failed. i would try swaping the run cap from the unit that wks ok lee

thats a good idea to try the parts out of the other. wish I would of thought of it when I had the covers off. justbuttoned it back up for the night.

any idea what the square "essex" item is that I mentioned?

I may pick up another capacitor if the local shop has it in stock for reasonable. Would be worthwhile to have a spare in the parts bin.

[jimzz2001]

Quote:

Originally Posted by D&J The box on the side of the compressor is the current overload. It sounds to me that you either have a start cap staying in the circuit because of a bad relay or a weak run cap. I would almost bet it's a bad run cap by what you are describing, I would replace it first and then the start cap and relay. If that doesn't fix it the compressor is bad. Denny

I am having difficulty locating the correct capacitors for my model # 600015-001.
If the price is decent I would like to replace the start and run capacitors. it's easy enough to take the covers off but I m tired of the up and down. any suggestions on a parts source?

[jimzz2001]

Quote:

Originally Posted by hometool i would be looking at the run capisator it may be bad causing high current draw either that or the compressor has failed. i would try swaping the run cap from the unit that wks ok lee

Ok I swapped out the capacitor (pictured with the orange and yellow wires) front a/c keeps tripping breaker shortly after it starts blowing cold air.

rear a/c works fine even after the capacitor swap. what now? we are going on vacation soon and don't like the idea of only 1 a/c in operation

thanks for any tips/suggestions

[jimzz2001]

Here are a couple other pics of the capacitor I swapped. is this what I was looking for?

[Ray,IN]

If you are trying to run both A/C units simultaneously on a 30A power supply, you likely caused low voltage to damage the compressor(s). You may quickly determine if the compressor is damaged from low voltage with a clamp-on Ammeter to measure current draw while the compressor is running.
Was the replacement capacitor a hard-start capacitor? This helps when you are pushing the amp limit of the power supply.

[Luv2go]

Try swapping the black box that the leads of the capacitor go to (along with most of the other wiring). This should be either a PTC, start relay, run cap or some combo of them. If it is bad it lets the start cap stay in the circuit when it should not be, cause the compressor motor to draw too much current and trip the breaker.

Make sure to put the wires back on exactly the same way they came off, your pictures will give you a good start at documenting this.