Air Conditioner Tripping Breaker

[TitanMike]

If the breaker only trips when the compressor starts I'd suspect the starting capacitor for the compressor.

If this small item has failed (and heat can cause them to do so) the starting current will go up drastically.

Here's a video that shows the process of replacing:

https://www.google.com/search?q=Repl...40PEPm6yE6AU25

If I was faced with a delay in getting warranty service, personally I'd replace the capacitor myself. They run around ~$20 and I can burn more fuel taking my TT to the Dealer for warranty repairs which is not reimbursed.

Capacitors are often available from local sources as well as Amazon and other online outlets. Electrical supply outlets that supply electricians are a good source too.

Just saying.

[RMWSierra]

Originally Posted by DerbyBailey

Our camper (2021 Micro Lite 22FBS) is only a few weeks old and been used almost full time those few weeks. Today, when the AC compressor kicks on, after a few minutes the breaker trips. Things we know and have tried (and yes, I read related posts I could find on this forum) :

- This happens with nothing (not even lights, no water heater, nothing) else running
- We are on shore power (dedicated 30A box on personal property)
- Weather has actually been cooler the last few days (south Texas)
- Tried shutting it all down and starting back up, no fix.
- All cables and plugs are good
- Breakers are fine as long as AC isn't running (fans, water heater, lights, you name it)

Again, we've been living full time in it for weeks, zero issue. Now we're without AC and that won't work during the day... can't take it to a shop, have no way to move it. Besides, wait times are so long and we need to live in it.

Brand new, only a few weeks in and this. Help!!

Need to check current draw on circuit. 20 Amp breaker may be weak.

[dward51]

Turn every breaker INSIDE THE CAMPER off. Then turn only the Air Conditioner breaker back on and start the AC.

See if it keeps running like it should. If it does, try flipping the Converter breaker (CONV) back on and see if all remains well. If not, your problem may lay in the converter and not the AC. Let it cycle through a couple of compress start ups and if all remains well, add one breaker back to the one position and wait again to see if something trips. Then you may have a better idea of where the problem is. The AC may be a symptom and not the actual problem source.

Also it's not unheard of for a AC capacitor to be bad or on the verge of being bad from the factory. It happens. If you have to change it out (should be a warranty item), I would also have a soft start kit installed at the same time since it all goes in the same location inside the AC housing. You may want to look at a Micro-Air "Easystart" unit.

https://www.microair.net/collections...nt=30176048267

[Frierson]

I would suggest find a Heating and cooling contractor to come and check your AC. They should be able to check the AC unit for you. I first might just replace the breaker that is tripping. The HVAC Contractor could likely do that while they are there. When finding the HVAC Contractor, let them know it is on your camper, hopefully you can find someone who is has worked on camper AC's before.
Good Luck!

[dsjohns71]

Mine did the same thing back in December as we had a warm day and I wanted to turn the AC on.. it kept tripping the AC breaker then as I was trouble shooting it it started stripping the main breaker and the breaker at the pole.. turned out being a loose neutral wire inside the junction box of the AC. It got really hot and melted the cheap wire nut the factory used and touched some metal, hence shorting it out.. its an easy check. Just take the filter out and you’ll see the junction box.. unplug the shore power for safety and pull cover off the j box in the unit and check for loose wires.. if that’s all good then maybe look at replacing breaker. Also check for loose connection at plug on trailer that the shore power plugs into. Just the vibration of going down the road and or the AC running may cause things to loosen up especially if someone from the factory did things half way.

[Larry-NC]

Originally Posted by HappyCamper1962

OK, these two points maybe help...
1) Any FR dealership can do warranty work, perhaps one closer to you has a mobile mechanic? Maybe you already tried that, not sure, so I mention it here.
2) New 30amp pole... well, when I had my 30amp pole installed at my house to support the camper, the electrician (yes he was actually a certified electrician) installed the wrong type of 30amp outlet - it was designed for a household dryer, not an RV. And the result was popping the AC camper breaker every time I turned on the AC. The RV 30amp circuit for an RV is different than what a standard electrician would be accustomed to installing. They type you need should be clearly labeled on your power cord and/or outlet cover on your RV. Maybe that's it?

Umm, the Original Poster did say that it worked for two weeks before it suddenly started failing. That makes your suggestion pretty unlikely.

[NXR]

With the A/C off, reset the breaker. Then gently rap the A/C breaker with the handle of a screwdriver a few times. If it trips with the A/C off then the breaker is defective.

If it does not trip, feel the front of the breaker immediately after it trips. If it's warm, the breaker is defective. A circuit breaker should never feel warm to the touch.

Ray

[DerbyBailey]

The 20a labeled conv is what keeps tripping.

[fonzie]

The 20 amp breaker is for the AC and not for the converter.

[eye95]

Originally Posted by DerbyBailey

The 20a labeled conv is what keeps tripping.

Mislabeled? If you can get the AC started, try tripping each breaker manually. See which one turns the AC off.

I suspect the labels on AC and Conv are switched.

[DerbyBailey]

I think the labels are right, just stuck on a bit high.

Did the main/AC breaker only test. It tripped breaker in less than 5 mins by running AC (only AC).

[fonzie]

You need to take voltage and current readings when AC is running to make proper diagnostic of what is wrong.

[DerbyBailey]

Originally Posted by fonzie

You need to take voltage and current readings when AC is running to make proper diagnostic of what is wrong.

Where would I take those readings?

[formerFR]

two suspects:

A) Your 20a a/c breaker itself may need to be replaced - they do 'go bad', but it's probably the second easiest 'fix' of anything....
turn off the 30amp main breaker, buy a $8 20amp tandem breaker(remove the 20amp breaker and take it with you to make sure you have the right/correct type), replace, tighten wire, done.

B) You may actually only have a LOOSE WIRE at the 20amp breaker - meaning that over time, and during your running of the a/c unit during those hot weeks, the wire became loose and is now making a connection when you 'start' the a/c, but when the compressor kicks on a amperage(HEAT) flows thru the wire, it can 'move', then 'arc', tripping the breaker. That's the SIMPLEST fix of all.
Turn off the main 30amp breaker, then tighten the outgoing black wire from the 20amp breaker. done.

[DerbyBailey]

Originally Posted by formerFR

two suspects:

A) Your 20a a/c breaker itself may need to be replaced - they do 'go bad', but it's probably the second easiest 'fix' of anything....

B) You may actually only have a LOOSE WIRE at the 20amp breaker - meaning that over time, and during your running of the a/c unit during those hot weeks, the wire became loose and is now making a connection when you 'start' the a/c, but when the compressor kicks on a amperage(HEAT) flows thru the wire, it can 'move', then 'arc', tripping the breaker. That's the SIMPLEST fix of all.

Any tips on where to find instructions on how to check those wires? I'm trying to walk my wife through it from where I am.

[fonzie]

Originally Posted by DerbyBailey

Where would I take those readings?

I would take the readings at the 20 amp breaker that feeds the AC. If you are not familiar on how to take these readings, then I suggest you get an electrician or RV tech that does. You will need a multi-meter and a clamp-on ammeter.

[formerFR]

turn OFF the Main 30amp breaker, and/or UNPLUG from shore power

- remove the cover of the breaker panel

- tighten the black wire coming from the bottom of the 20amp breaker
(pull the breaker out if you can not access the wire/screw easily)

- then clip the breaker back in if you've removed it

- plug shore power back in

- flip the 30amp Main breaker on

- turn on the 20amp a/c breaker

- turn on the a/c unit and see how long it stays on


replacing the breaker is the same ...

[formerFR]

a breaker TRIPS because it is designed to do so for SAFETY reasons, GENERALLY because too much Amperage is flowing thru the wire connected to it - this can happen when an appliance or device requests too much power, more than the breaker is designed to handle, but it can also happen, especially in 'moving' RVs, when a loose wire starts to 'arc' when it does not have a good connection at the breaker.

Now, 'could' a similar loose wire be at the a/c unit itself? Maybe, but don't worry about that until you know the breaker wire, or a new breaker, is not answering the problem.

[Larry-NC]

Originally Posted by DerbyBailey

I think the labels are right, just stuck on a bit high.

Did the main/AC breaker only test. It tripped breaker in less than 5 mins by running AC (only AC).

The labels are always either too high, too low, or printed at a different pitch than the actual breakers. I'm not sure why they never get it right. It's not rocket science.

[Larry-NC]

Originally Posted by NXR

With the A/C off, reset the breaker. Then gently rap the A/C breaker with the handle of a screwdriver a few times. If it trips with the A/C off then the breaker is defective.

If it does not trip, feel the front of the breaker immediately after it trips. If it's warm, the breaker is defective. A circuit breaker should never feel warm to the touch.

Ray

Ray, there are two kinds of breakers, Magnetic and Thermal.

The force of an electromagnet is defined by the product of current and the number of turns of its coil. A magnetic breaker is designed such that it trips when the current is high enough that the internal electromagnet trips the breaker to the open state.

A thermal breaker uses an element something like the bi-metallic element in a thermostat. When the current through the element makes it hot enough, it trips by opening the switch. No more current flows, so it cools down. These breakers get noticeably warm, even when operating within limits.

The above is, in both cases, a mechanical oversimplification. In each case, the internal switch is sprung such that it's normally open. When you reset it, you push against the spring until it latches. What the magnetism or temperature actually does is release the latch so the internal contacts snap apart. This eliminates sustained arcing that would occur if the breaker contacts separated slowly.

I just bought a replacement 10 amp, 120 Vac thermal breaker last week. And here are the specs for it.

And if you've ever wondered why people will say that breakers will trip with less current when the ambient temperature is high, the answer is that they are talking about thermal breakers. Obviously it takes less current to reach the trip point if the ambient temperature is 100F than if it's 60F.

And in case you're wondering whether the breakers in an RV or home were thermal or magnetic, the answer is "both." It gives fast tripping on huge overcurrents, but eliminates nuisance tripping on brief, small overloads like motor startup. Here's a catalog page from a company you probably know, Square D.