AC tripping in extreme heat...need suggestions!

[bren0035]

Ok, I'm new to this forum and usually don't need to ask for this type of help as I have a good group of people that have been trailering for many years and are good at answering my questions. I'm at a loss and wanted to see if anyone on here had some ideas. Here are the details for all you trailer Dr. out there.

I just bought a used 2007 KV Sportsmen (38 ft) travel trailer. We restored the interior of the trailer and before going out camping I checked everything I could, i.e., fridge, lights, water, toilet, sink, etc. We bought this trailer to use in Havasu/Parker Dam, CA. The temps in the summer are constantly in the 110-118 range so it gets hot and stays hot all summer.

I have two AC units on my trailer. The guy I bought it from installed the second (rear) AC on its own seperate breaker and upgraded the electrical to 50amps. THE PROBLEM I HAVE IS I CAN'T SEEM TO KEEP THE MAIN AC TO STAY ON!!! The back one will stay on all day and night and blows freezing cold air, but the main one has issues running during the day, BUT will stay on at night with little issues. It trips the breaker around 11-12pm during the day and will keep tripping every time I reset it. Once it gets to be around 8-9pm at night and the sun is down, I can flip it back on and it usually stays on all night or sometimes will trip once or twice, but then will stay on all night and blow cold air.

I thought it might be pulling too many amps because it was dirty so I got up on the roof the following trip and cleaned it real good. I also replaced the breaker. Still trips! I placed a fan on the internal breaker box thinking that maybe the breaker is getting over worked and hot, but it still trips. I'm thinking it has to do with heat as it trips right when it gets extremely hot, but why would it still trip if the AC inside was still cold? Will the AC trip if the external unit get too hot? Why does the back one stay on all day and have no issue?

I've also tried turning the back one off and letting the main one work and pull amps by itself, but the same thing happens. It's hard to trouble shoot because at one point the AC will work for many hours without problem.

I've had some people say to try putting that unit on a 25-30 amp breaker and put it on the bottom of the box so there's some space in the breaker box and allows for better ventilation. I'm fearful that I could allow the AC to fry itself, but believe the idea was that the AC was trying to run harder to keep up with the hotter temperature. Again, why would the back one have NO issue at all. They are both Coleman.

Sorry for the long post, but I need to figure this out or staying out there will continue to be a huge frustration for us. The back one can't keep the trailer cool during the late afternoon.

Thoughts.

[jyrostng]

When cleaning the rear coil, protect the fan motor from water spray. The bottom of the motor is open, too much water in the motor and it will short out. A plastic bag around with tape usually protects it.

The sheetmetal shroud around the rear fan is usually attached with screws and you can slide it forward to get to the rear coil better, you"ll be amazed sometimes that the unit can work at all as stopped up as the coil is

[dodge_guy]

I don't have an issue with the breaker tripping, but the last few years I noticed the A/C wasn't working as good as it was the first few years. So I got up on the roof and opened up he A/C and found about a quarter of the coils in the corners covered in gunk. I brushed them, blew it out from the back side and brushed some more then blew it out some more. Then I rinsed them out. It was loaded with dust in between the fins/tubes. I hope it's back to normal where it will cool the entire trailer on a 95deg day. I'll see in 2 weeks when we go out west!

[dfletch]

I had a similar problem on my old MH. Unit would draw more current on hot days. I got a gallon of coil cleaning fluid from commercial AC supply store diluted it as directed and used a garden sprayer. Got on the roof removed the Cover and soaked the coils then flushed with fresh water. You would be suprised all the junk that came out of the coils. Used shop back to suck up excess water and junk. AC worked much better after that.

[colliehauler]

yillb wrote:

jyrostng wrote:
Those units blow the air through the back coil from the inside out. The part of the coil that gets dirt on it is on the inside facing the fan. When the ac unit isn't able to blow enough of the heat out, it makes too much pressure, this overloads the compressor, causing the amps to rise. Make sure the rear coil is clean and the fins are straight and not folded.

Listen to this guy, almost guarantee that's your problem.

This, X-3

[FrankShore]

Could you go back to or call the former owner? He should have some sort of trick that will get it up and running. Or if dealer bought, call the dealership and explain your problem, etc

[yillb]

jyrostng wrote:
Those units blow the air through the back coil from the inside out. The part of the coil that gets dirt on it is on the inside facing the fan. When the ac unit isn't able to blow enough of the heat out, it makes too much pressure, this overloads the compressor, causing the amps to rise. Make sure the rear coil is clean and the fins are straight and not folded.

Listen to this guy, almost guarantee that's your problem.

[jyrostng]

Those units blow the air through the back coil from the inside out. The part of the coil that gets dirt on it is on the inside facing the fan. When the ac unit isn't able to blow enough of the heat out, it makes too much pressure, this overloads the compressor, causing the amps to rise. Make sure the rear coil is clean and the fins are straight and not folded.

[krobbe]

Can't really troubleshoot it without knowing the voltage and current when it trips. When voltage decreases, current increases. The breaker trips when the current goes high enough to exceed the trip rating of the circuit breaker. Don't change the circuit breaker with a higher rated one. They are there to protect the wiring from overheating and burning down the trailer. If voltage and current is normal for that circuit, replace the circuit breaker with the same current rating. They do wear out. Especially when they experience a few overload trips.