Not sure if you’re running off of a generator or you hooked to a landline. If you’re running the generator you might try turning off your converter, that might give you the extra power you need to run your air conditioner.
- Disconnect power to coach
- Remove front panel of AC breaker panel
- Identify breaker for AC in question
- Remove said breaker and tighten screw
that secures the black wire to it
(usually a #2 square drive)
- Tighten neutral (white) and ground
(bare) wires at their bus bars)
- Put it all back together, restore power and test
When running the AC load for a while before it trips the breaker feel the insulated part of your shorepower plug, the insulated part of your trailer connector plug (if you don't have the reel). You can also feel the front of the inside mains and air conditioner breakers with a bent over index finger. Excessive heat usually means bad connections. Taking DVM readings at the feed wire to the Air conditioner in the breaker box measured to neutral can tell you if the AC is getting low voltage. Try taking voltage readings on this wire with the AC both not cooling and cooling. A large difference in voltage under load (ac ON), indicates voltage losses in the wiring feeding to the AC breaker, and prob able bad connections somewhere. A clamp on ammeter on that black AC feed wire can easily give you a true idea of how much current your air conditioner is pulling. Maybe your breaker is weak.
There is supposed to be a overtemperature switch on the top of the AC compressor that will trip in a combination of high heat and AC working inefficiently. But when this happened on mine, it simply cut the compressor off, but kept blowing air. I put an external fan on the outside of the shroud blowing air on the top of the compressor, which helped, but I eventually got a new AC unit. My new unit is running for hours on end toady with the peak afternoon temperature over 110 degrees, here in Porterville. It will shut off about 11pm tonight.
You did not say what your rig is. I have a power real and my did the same thing in the desert with 104 degree heat. It turn out to be a loose neutral leg inside the power real. If you have a power real, unplug, make sure you do not have a generator running, and pull the entire cord out of the real. This exposes the hatch in the center of the power real and open it. Check the connections. Also, If you have a gen prep with or without a generator, check the connections in the transfer switch.
After going out to dinner I came back and browsed around the net for a Dometic chart of Air Conditioner current draw vs ambient temperature I remember seeing before. I never did find it, but read some other interesting stuff.
1. Is your AC unit on a 20 amp breaker? Even though the AC unit nominally pulls 12-13 amps, it should NOT be on a 15 amp breaker/wiring. According to what I read the breakers need 20% headroom for constant current draws.
2. Have you inspected the rooftop evaporator and condenser coils for dirt and debris clogging airflow?
3. Give your blower fan motor a manual spin. It should spin freely, and helps cool the compressor. One guy said that the blower motor bearings were binding, and replacing the blower motor fixed the problem.
4. Seal up all of the cross air leaks in the input/output inside plenum box. Air leaks between these 2 subsystems lower cooling efficiency.
5. A leaky start/run capacitor may be causing the problem, and is worth a try to simply swap it out to see if the problem goes away.
My Bighorn has the 15K BTU Dometic Brisk Air II fused with a 20 amp circuit breaker. I think in reading the Dometic manuals, this is what they specify. A normally running 15K BTU AC pulls about 12 amps, so maybe a 15 amp breaker isn't enough "headroom".
This has been a whole week with temps in the AZ desert over 100 each day and the forecast for the next week is every day above 100 as well. I finally came up with a solution that allows the main AC to keep from tripping breaker. Both AC units are 15K.
I created the RED NECK Desert Shade!
I bought a small pop up shade at WalMart (4x6) and a small blue tarp (5x12) and assembled a shade device over the main AC (rear of coach). I did not extend the legs beyond the folded up size. I only attached the tarp with zip ties to the south and west sides to maximize shade but minimize impact of wind.The main AC never tripped the 20 amp breaker after this modification and the bedroom AC has never tripped its 20 Amp breaker. Used round soft rope (see red rope in photo below) to tie down shade to bottom of coach which so far has kept all things tight without damage and we have has some 15 to 25 mph winds so far. I was lucky there was no wind when assembling this system on the roof! It was definitely an early morning project
I placed each foot of the shade in a bucket to minimize potential to damage the roof.
I also tied an umbrella to the pedestal to provide shade on the surge protector plus unrolled the power cord and made sure it was in the shade under the coach.
With 8 small fans running inside & the water heater off during the day Line 1 (bedroom AC) pulls 14 amps, Line 2 with refrigerator on electric (gas needs repair to work) pulls 26 amps.
With this set up plus all dark shades down and awning out we have been able to keep the max temps in the coach in the mid 80's during the day (68 at night) and did not have to replace the dual circuit breaker in the coach yet but have a replacement ready.
The smart thing would have been to move the whole rig up into the mountains where the temps are cooler but have commitments here in the heat of the valley.
Definitely not an elegant solution but park manager has approved
I did something similar to my WHOLE ROOF while I was staying in the hot California Central Valley in Porterville with daily summer temperatures over 100 degrees. I started with just my air conditioner cover shroud, covering it with the combination reflective foul bubble wrap construction insulation. That seemed so effective at reflecting the IR heat that I bought a a 100 foot by 4 foot wide roll of the same insulation ($150) (https://www.homedepot.com/p/Reflect...-Reflective-Insulation-Roll-BP48100/202092205 ), cut 2 - 38 foot lengths to cover my roof, patched these 2 lengths side-by-side with heavy foil duct tape, and installed it on the roof with cutouts for the AC and roof protrusions. I secured the reflective cover down to the sides of the roof with the same heavy foil duct tape. Since I was staying in one place, this worked OK for me. I also covered the slide tops this way. I gave most of this stuff away to other RVers when I finally moved on. I have had the same insulation over all my windows for the couple of years, taking it down when I moved.
I talked to an RV service guy who does the white roof sealant process, and he said that after his sealant is applied you can walk barefoot on the roof in hot temperatures. I know that when I was working on the original rubber roof, and the temperature was 75 degrees or above, I had to have rags or gloves for my hands when I was crawling around due to the hot roof. The roof coating is on my to-do budget list. Right now I am staying outside of San Diego where it hasn't gone into the 90's all week.