Air Conditioner pops 20A breaker

kev2504 · 06-02-2010, 11:29 AM

My Air Conditioner this past weekend was poping the breaker.
When we first bought the unit it did the same thing, and the dealer came out and installed a delay on the compressor, so the fan and compressor did not turn on at the same time. All was good.
This past weekend after about an hour or so of running it poped the breaker.
This happened twice. Does anyone have any suggestions?

NWJeeper · 06-02-2010, 11:34 AM

Are you talking about the breaker in the RV itself or in the garage or the pedestal where it is plugged in? I don't see the point of the time delay relay as they are usually only used to keep the compressor from cycling on and off if you switch the thermostat on and off quickly. I have never heard of using the TDRs on RV air conditioners. It isn't beyond possibility that there could be something wrong with the compressor which is bogging down the motor to the point where it is popping the breaker. A TDR doesn't fix that. Sounds to me like the dealer didn't want to actually do any work to diagnose the problem rather put a band aid on it and hope it goes away.

chevy02 · 06-02-2010, 08:01 PM

you should be on at least a 30amp breaker A/C probably drawing that much by it self so any thing else running electric will cause it to overload and throw the breaker

milzat · 06-02-2010, 08:21 PM

The A/C is designed to draw only 20 AMPS.

There are a number of things that can cause the breaker to "TRIP". A breaker "TRIPS" because of the build up of heat. Many things can cause a breaker to heat up and "TRIP". I'd start with the connection(plug). Make sure you have a good connection at the campground pedestal, then go from there. Some older campgrounds will give a breaker "TRIP" problem. Wiring gets bad, receptacle contacts get tarnished, etc...

GingersDad · 06-02-2010, 09:03 PM

Not knowing to many details about the unit. I would check all easily accessable connections and plugs. Next pull the cover on the unit to see if the fan turns freely and while you are there look for the Capacitory. It looks like a small soda can (can also be black plastic) cylinder with serveral wires coming out of the top. This stores up current for use when the units kicks on. If this happens to be the area that is causing the problem it will only get worse as you keep turning the breaker on and running the unit. I was able to track down a local A/C repair person and he had on his truck for about under $30.00. An easy cheap fix if this is your problem. While you have the cover off see if there is a place to lubricate the fan.

Radio · 06-02-2010, 09:19 PM

Quote:

Originally Posted by NWJeeper

I don't see the point of the time delay relay

The idea, as I see it, is to reduce the amount of instantaneous current draw on start up. Both the compressor and fan motors pull the most current when starting. If you start one, say the fan, let it come to speed (and minimum current draw) then start the compressor, it reduces the peak current and lessens the amount of voltage "sag"

Instead of one huge current peak you have two smaller ones

A system like that I think would make the motors in the unit last longer and pop fewer breakers on starting.

*****

It also occurred to me that the line voltage drops in the summer as everyone has their A/C running. In my subdivision, built about 1988, the grid will sag a bit during peak usage times. This could be aggravating your problem.

You might invest in one of those voltmeters you plug into an outlet in the RV. I have one, and that's how I know the grid sags a bit in the hot afternoons.

jamesp · 06-02-2010, 09:36 PM

Last year on our first rip out, I had a similar problem with the AC tripping the AC breaker in the camper when it would cycle and shut off. After considerable stress, I turned the electric hot water heater off and ran it on gas and the problem ended. After calling a mobile service man, he told me to leave the water heater off and that I most likely had a bad element a bad element in the hot water heater and it was contributing to the breaker tripping. When I returned home, I replaced the element and at the service man's suggestion the AC breaker. It has worked perfectly ever since.

NWJeeper · 06-02-2010, 09:59 PM

Quote:

Originally Posted by Radio

The idea, as I see it, is to reduce the amount of instantaneous current draw on start up. Both the compressor and fan motors pull the most current when starting. If you start one, say the fan, let it come to speed (and minimum current draw) then start the compressor, it reduces the peak current and lessens the amount of voltage "sag"

Instead of one huge current peak you have two smaller ones

A system like that I think would make the motors in the unit last longer and pop fewer breakers on starting.

*****

It also occurred to me that the line voltage drops in the summer as everyone has their A/C running. In my subdivision, built about 1988, the grid will sag a bit during peak usage times. This could be aggravating your problem.

You might invest in one of those voltmeters you plug into an outlet in the RV. I have one, and that's how I know the grid sags a bit in the hot afternoons.

Yeah, I fully understand the purpose and thinking behind the TDRs but they have never been needed on RV air conditioners in the past so this case didn't make sense to me. The use of the TDR to me seemed like a band aid fix by a dealer service center that didn't want to dig further into the problem. Since an RV air conditioner can be run on 20 amps with no other large current draw items running, merely delaying the full use of current doesn't fix anything. I see the TDR as unnecessary when no one else needs them and something else needs to be fixed or remedied.

Perhaps like the other gentleman here who's AC was freezing up this person is running theirs too long trying to get down to a temperature that the AC is not designed for. Just a thought. He states that it pops the breaker after an hour of running. That is a long duty cycle if the compressor is running the entire time, maybe trying to get down to an unobtainable temperature. Just throwing out ideas here but surely the TDR wasn't the fix as it still has the same problem.

LadyWindrider · 06-03-2010, 06:51 AM

Until the first question is answered, which breaker, I don't think we can go any farther. While the AC MAY run on a 20 amp breaker, it's highly unlikely the camper will run the AC on a 20 amp circuit with a 15 AMP adapter. Also one must remember, the hotter it gets outside the more current the compressor will draw due to pressures being higher in the system, so while it may work at 70 degrees, it may not at 90 degrees. One last thing, that long extension cord coming from the garage isn't helping either, especially if it is 14 gauge or smaller. Sorry, too many unknowns here to make any kind of proper diagnostic help.

MtnGuy · 06-03-2010, 07:21 AM

Quote:

Originally Posted by GingersDad

Next pull the cover on the unit to see if the fan turns freely and while you are there look for the Capacitory. It looks like a small soda can (can also be black plastic) cylinder with serveral wires coming out of the top. This stores up current for use when the units kicks on.

It is my understanding that you can get quite a shock from a charged capacitor, so be careful up there.

milzat · 06-03-2010, 08:20 AM

OK..

Let's go back to the original post.

kev2504, exactly which breaker is "TRIPPING"? Is it the A/C breaker or the MAIN breaker?

GingersDad · 06-03-2010, 08:30 AM

The capacitor that I changed was completely fried and all current was drained from the unit. ALWAYS, make sure the current is turned off and when in doubt let a professional do the work. The experience I had with the capacitor was at Frontier Town, OC, MD and the service person their lent us a ladder and helped us track down the part. They usually keep them on hand, but since it was July they were out of stock.
Also as Jamesp stated your Hot Water heater if running on electric can cause a problem. A good starting point when any breaker trips is to see how many things are ON at the same time. Coffee makers, hot water heaters, space heaters, microwaves, tv's all add up especially when running at the same time.

kev2504 · 06-07-2010, 01:13 PM

The breaker that trips is the 20 amp A/C breaker in the trailer.
The delay is so the fan and compressor do not both turn on at the same time. They both draw the most at start up, so by delaying the compressor it has helped.
Kev

LadyWindrider · 06-07-2010, 02:05 PM

Now that we know which breaker, we need to know what you are plugged in to? Extension cord? 30 amp to 15 Amp adapter? Then you need to have a voltmeter, and a friend. You need to measure the AC voltage at one of the wall plugs with nothing on. Then you turn on the AC and watch for a voltage sag. Continue watching, and see if there is another when the compressor kicks in. This is one time an Analog is much better than a digital, as a digital won't react fast enough. Last measure AC voltage with the ac running, compressor on. Report back what you find please.

kev2504 · 06-07-2010, 04:20 PM

The camper is plugged into a 50 amp to 30 amp adapter cord, which is plugged into a 30 amp service at the campground.
I will check the voltage this weekend and report back.
Thanks,
Kev

jamesp · 06-07-2010, 07:49 PM

I would also suggest replacing the breaker. You can get them from the big box stores or an electrical supply. I understand they weaken after repetitive use. I replaced mine after my problem. Just unplug the power, pull the negetive wire from the battery, and go to work. Ten minute job at the most and I think around $10.

LadyWindrider · 06-07-2010, 09:30 PM

Help me understand. You have a camper that requires 50 amp. You are plugged in at a campground with only 30 amp service, so you are using a 50 amp to 30 amp converter, and plugged in to a 30 amp service. That's my understanding. Now what does your camper have? 2 air conditioners? Electric hot water (factory or added)? Washer/Dryer (factory or added)? Microwave (factory or added)? Did you buy new or used? Sorry for all the questions.

Explanation: 30 amp will run one AC and maybe a small microwave. If someone added electric hot water, dryer, microwave, etc., 30 amp will not carry it. They may have something added on the AC breaker which is causing the problem. I know I sound like a pain, but you have to be my ears, eyes, and hands on this. Since you are going back, try and get a cheap analog meter. Will show voltage swing much faster than digital. Will have to check voltage several places. Anything below 100 volts will cause trouble. I agree, a delay is not the fix, on;y a band aid on the real problem. And the hotter it gets, the worse it gets.

kev2504 · 06-09-2010, 08:22 AM

My trailer is a Salem 4022B, which has a 50 amp service. The campground has 30 amp, so I have a short cord that converts from the 50 amp plug to the 30 amp plug. I was running the water heater on electric due to an issue with my heater not lighting (another thread). But, the breaker that is tripping is the 20A in the trailer for the A/C. I will replace my fuel valve on my water heater to get that to light on gas.

It is supposed to be in the 90's on Saturday, so this will be a good test for the A/C. I will check the voltage, first in the trailer, then at the pedestal, to compare. I did think about replacing the breaker.

Question: If my trailer was using more than 30 amp's, the breaker that would trip would be the campground breaker, not the one in my trailer, right?

**Herk7769** · 06-09-2010, 08:34 AM

Quote:

Originally Posted by kev2504

My trailer is a Salem 4022B, which has a 50 amp service. The campground has 30 amp, so I have a short cord that converts from the 50 amp plug to the 30 amp plug. I was running the water heater on electric due to an issue with my heater not lighting (another thread). But, the breaker that is tripping is the 20A in the trailer for the A/C. I will replace my fuel valve on my water heater to get that to light on gas.

It is supposed to be in the 90's on Saturday, so this will be a good test for the A/C. I will check the voltage, first in the trailer, then at the pedestal, to compare. I did think about replacing the breaker.

Question: If my trailer was using more than 30 amp's, the breaker that would trip would be the campground breaker, not the one in my trailer, right?

However low volts could be overloading the AC compressor and that is why the AC breaker is blowing.

kev2504 · 06-10-2010, 04:27 PM

We are going up tomorrow afternoon. I will use my digital meter to do the testing. It should be good enough to at least tell me if the voltage drop is the problem or not. If all else fails, I'll just put a penny in, just like the old fuse days. Just kidding.

Kev

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