Should I be concerned w/Air Conditioner

[k9jkfham]

I have a Dometic A/C with Heat Pump. Outside Temp 89-90 (Very Humid) Inside temp 77 to 79 Temp of air from ducts about 55.

The unit just keeps running and does not hardly ever shut off in daytime. Night time is OK.

The last 2 days the unit has blown a fuse. Restarts Ok and reset of fuse.

First time I have had a unit like this. I am concerned about the unit running all the time since we are about to depart on a 6 week trip out west.

[wahoonc]

Sounds about right to me...

What color is your unit? Parked in the shade or full sun? Most RV's are not particularly thermally efficient. You have to heat and cool by brute thermal force.

I have a 31' Concord and it is not unusual for the AC unit to run non stop on hotter days until after the sun goes down. Right now it is 94° at my house with 43%Rh, the unit is set on 80° and hasn't shut off since 10 this morning. Don't expect it to shut off until 7pm or so. FWIW my old house with poor insulation does the same thing. The house AC has been running non stop since noon.

Aaron

[5picker]

Pretty normal to run non-stop trying to keep these poorly insulated boxes cool.

It isn't normal to blow fuses.
What fuse blew?

The A/C unit is protected by 120v circuit breakers.
Some (but not all) thermostats have 12v fuses protecting their circuitry.

A bit more detailed information might help us help you.

[Witch Doctor]

Originally Posted by 5picker

Pretty normal to run non-stop trying to keep these poorly insulated boxes cool.

It isn't normal to blow fuses.
What fuse blew?

The A/C unit is protected by 120v circuit breakers.
Some (but not all) thermostats have 12v fuses protecting their circuitry.

A bit more detailed information might help us help you.

X' s 2 are calling your 120v breaker a fuse? You can trip a breaker if the unit short cycles, the compressor has to equalize about 2 mins or it will hit lock rotor and trip it. This can be caused by playing with the stat is one way. I know of no fuse to your stat wire. Also when it's hot out you could be flash brown outs on the CG power, sudden off and on like a blink will also cause that your #'s say it is doing all it can, that's a good temp drop.

[k9jkfham]

It was the 20 amp circuit breaker that keeps tripping. I have a WFCO power distribution panel. Since my last post the weather is cooler, sun has gone down and the circuit breaker has tripped 2 times. And the unit has not shut off.

I have the thermostat set at 80 and still running.

Any ideas or suggestions.

[k9jkfham]

The unit is white and is parked in the direct sun for part of the day. It is protected on one side by a 1 story building and by trees. From about 11 AM to 4 PM in direct sun, then protected by lots of trees.

[Witch Doctor]

Originally Posted by k9jkfham

The unit is white and is parked in the direct sun for part of the day. It is protected on one side by a 1 story building and by trees. From about 11 AM to 4 PM in direct sun, then protected by lots of trees.

It's doing all it can, your just gaining more heat then it can keep up with, like I said the discharge air tells you that from the inside temp your getting a good split, what you are getting is called nuisance tripping in the industry. Check the tightness at the breaker, or common is a weak breaker. Lose wires causes heat which will make it trip. If the wire is tight not snug, put a new breaker in, did HVAC for 25 years, just a little advice . Good luck, should end your problem.

[wahoonc]

If it is the breaker in the RV that keeps popping you may have a weak breaker, new ones aren't all that expensive. There is also a possibility of the AC drawing a bit too much current for some reason. Only way to tell is with an ammeter.

The direct sunlight is what is causing your heat build up. The white color is a plus though.

Aaron

[mwdilday]

I am not sure it is doing all it can do. It should not be tripping breakers frequently. In fact, after 25 years and a dozen units with A/C I have never had issues with them tripping breakers. The only way to tell if the unit is "doing all it can do" is to check the temperature differential between the air entering the return and the cold air coming out of the vent. You should have at least 16-20 degrees differential. Also, have you checked your air filter on the return? It sounds like the unit may be starved for return air. That would cause a high head pressure, excessive amperage draw and poor cooling.

[Skip12]

Another thing to check - Be sure all roof vents are closed. With our last camper, when we left the bedroom roof vent open, the AC could never catch up.

[jonwisconsin]

In my experience with my Lep, I can only expect the A/C to do no more than 10-15 degrees cooler inside when it’s hot outside and it’s under the sun. I had the breaker tripping. I don’t know what caused it but two things I did. One, was making sure the electric water heater was off and tight the connecting wires of the A/C breaker. The dealer looked at it and found nothing. The campsite post can cause this kind of problems if it’s not the best.

[TLAK]

A dirty air filter can make it act like that.

[valleyduo]

Check any ground wires for the blown fuses. Grounds always seem to get corrosion or work loose. As for the interior temps, sounds about on par for camper life. When we camp with the weather in the 90's, we Velcro some prodex insulation sheets to all of our window frames, as well as insulating the ceiling vents. We can usually maintain a 15-20 degree temp change and the ac will actually kick off from time to time, but not for very long. Save showers for after dark, limit opening doors, and cook outside.

[Witch Doctor]

This is a good point also, to the OP do you have your front windshield covered? That sun would be a killer coming through.

[cavie]

Install a "Hard Start" capacitor on your AC.About $12.00. Put you WH on gas. Use a voltmeter and see how much voltage you have at the pedestal. With everyone else using AC I'll bet you have low voltage. You should check the voltage at every campsite. I'm on a permanent site. I have only 108 volts when the camp is full. I installed an "Auto-transformer" it busts the voltage up to allowable #'s. Everyone has a different opinion of that # I want to see 117 to 127 volts.

[k9jkfham]

Thanks to everyone for replying. All good information that I will check and use.

[brfriend0]

Start with the easy things first, make sure the condenser coil on the roof is clean.
Cottonwood can plug them up in a day or two if you're located near a tree when the cotton is flying.

[AquaMan]

Something no one has mentioned (that I saw), if your voltage drops, your amperage will increase and can trip the breaker. An EMS can protect you if this is happening. Check your voltage at an outlet during peak operating hours.