30 amp for duel AC

[Carol_N]

Considering buying a Big Horn with dual AC system, will it run in 30 amp services?

[christopherglen]

I can and do run both AC's off a 30 amp service. The lake does not have 50 amp, so 100+ degree days need both to stand a chance of sleeping. I have to turn off the converter (battery charger) and run a minimum of lights, fridge on propane no microwave or electric water heater. Biggest issue is starting one ac, and letting it run a min before starting the other. Once they start cycling, it gets exciting. I do usually trip the 30 amp breaker once or twice a trip.

[jimmyfred]

Carol N wrote:
Considering buying a Big Horn with dual AC system, will it run in 30 amp services?

.........You could probably run two small 5,000 btu window units on 30 amp , minus any microwave or electric water heater usage ! , jf

[Vette_Racer]

You can run both off a 30 amp service if they are 13.5 high efficiently AC units as they only use about 9.5 amps and you limit your other use.

[DReisinger]

It is a Dometic, Model RM 2862 It's in my 05 Cardinal

[Cummins12V98]

Carol N wrote:
Considering buying a Big Horn with dual AC system, will it run in 30 amp services?

I think a closer reading of the OP's question is in order. He or she are asking if the two AC's will run on 30A "SERVICES".

Any modern RV with TWO AC's will have a 50A system.

The answer is YES by turning off all major electrical draws and running them on propane if possible.

Yes I have run bOTH AC's on our 07.5 MS on a 30A SERVICE.

[enblethen]

Make and model?
I would say the circuit board is suspect.
I am guessing that the 120 volt relay is stuck with contacts closed.

[DReisinger]

Since we are talking refrigerators, I can't turn mine off, as soon as I plug into SHORE POWER, it comes on. Doesn't matter if the lights on the front are on or off, I can push the on/off button, the lights will go off but not the fridge. Unhooked the shore cable and have a charger on the battery, to keep it charges, gas bottles are off.

[Coach-man]

Not in the A/C refridgerator business, but I have heard on many occasions that abruptly shutting down the compressor while operating has a deterious effect that may cause it to fail! Tripping the circuit breaker would have that effect wouldn't it?

[Allworth]

Downstream equipment is protected. That is WHY the breaker trips.

(If high demand causes a low voltage situation, that is a whole nother worm-can.)

[Charlie_D_]

OP-At a campground I meet a man who had 30A service to his rig. He added a second AC in the bedroom and the installers ran a wire in the ceiling and behind the bathroom sink to the bottom outside of the RV. He then runs an extension cord to the campground breaker box. May not work for you but may be an option.

[Walaby]

If a CB exceeds 80 percent on continuous load, and overheats, would it not trip? The overheat and subsequent trip doesn't hurt the equipment does it? I think that is what WRVPO was trying to say by saying it's either on, or off... If it is drawing 28 amps, and overheating, I don't THINK it is a smart CB and throttles back to reduce overheating, it logically would trip (or catch fire maybe?)?

Point being it could certainly create issues, but if the equipment is drawing 28 amps and the circuit is providing it, the equipment continues to run until the circuit trips, burns up or what have you, right? And if the circuit trips, the equipment quits and for the most part, if equipment does that, it recovers okay.

Mike

[Coach-man]

CA Traveler wrote:

westernrvparkowner wrote:

valhalla360 wrote:

Mandalay Parr wrote:
I can run both of mine on 30. They draw about 27-28 total. One is a 15 and the other 13.5.

Keep in mind a 30amp is really only rated for 25amps continuous. Drawing continuous 27-28 amps is a good way to burn out equipment. If you are lucky it just trips the circuit breaker.

You may or may not be able to get both units going but it's really a not a good idea.

Huh? What gets damaged drawing 27 amps? A breaker only has two positions, on or off. If it is on, the power being delivered will be 120 volts +/- 5 percent per NEC. If it is tripped to off, the power being delivered will be zero volts +/- an infinite percent (zero times anything is still zero). Where things get damaged is when voltage fluctuates high or low. The only possible damage would be if something gets harmed by the power suddenly cutting out due to a breaker tripping. Almost all appliances are built with that potential in mind so they aren't going to be damaged. The biggest threat would be if something got harmed because the appliance stopped working. Pets might overheat if the AC quits and the Chicken Fried Steak is going to be mighty greasy should the electric frying pan cut out in mid fry, but the skillet and the AC unit will almost assuredly continue to work once power is restored.

Western... lots of very good information from you but this isn't one.

The NEC recommendation is to limit the loads to 80 percent for CONTINUOUS loads which is basically what A/Cs can represent and what he posted. The concern is not voltage or appliances but rather the heat generated at the plug with continuous loads.

Careful examination of a typical 30 amp receptacle will show it has been overheated! You almost never see a 50 amp receptacle in the same condition. This shows that overheating is a big problem with 30 amp sites!

[CA_Traveler]

westernrvparkowner wrote:

valhalla360 wrote:

Mandalay Parr wrote:
I can run both of mine on 30. They draw about 27-28 total. One is a 15 and the other 13.5.

Keep in mind a 30amp is really only rated for 25amps continuous. Drawing continuous 27-28 amps is a good way to burn out equipment. If you are lucky it just trips the circuit breaker.

You may or may not be able to get both units going but it's really a not a good idea.

Huh? What gets damaged drawing 27 amps? A breaker only has two positions, on or off. If it is on, the power being delivered will be 120 volts +/- 5 percent per NEC. If it is tripped to off, the power being delivered will be zero volts +/- an infinite percent (zero times anything is still zero). Where things get damaged is when voltage fluctuates high or low. The only possible damage would be if something gets harmed by the power suddenly cutting out due to a breaker tripping. Almost all appliances are built with that potential in mind so they aren't going to be damaged. The biggest threat would be if something got harmed because the appliance stopped working. Pets might overheat if the AC quits and the Chicken Fried Steak is going to be mighty greasy should the electric frying pan cut out in mid fry, but the skillet and the AC unit will almost assuredly continue to work once power is restored.

Western... lots of very good information from you but this isn't one.

The NEC recommendation is to limit the loads to 80 percent for CONTINUOUS loads which is basically what A/Cs can represent and what he posted. The concern is not voltage or appliances but rather the heat generated at the plug with continuous loads.

[Lantley]

jaycocamprs wrote:

Lantley wrote:

enblethen wrote:
Device looks very similar to Progressive Dynamics cheater box. It specifically says no GFCI and receptacles must be on separate circuits.
Cheater box

It is nothing like a cheater box. This unit is hardwired into the RV. Two different animals.

So it is a transfer switch that transfers just 1 AC unit off the main trailer power over to the dedicated 20-amp circuit. And by transferring both hot and neutral, the load thru the GFCI is the same on both hot and neutral

Yes and it works....
Once you grasp, believe,understand,trust that it really works.
You will hopefully see the game changing possibilities of the device. I did and It will change my camping destinations. OPtions always have options. Being able to use both AC's on a 30 amp sites will give me lots more options.