Community Forums

Sweetbriar · 06-16-2018, 09:13 AM

I have also run both 13.5K BTU roof A/C's off 30 amps. Water heater on propane and a full charge on the battery bank before switching on A/C #2 (limit power demand of the converter). Fridge is residential. Highest steady power demand I've measure has been 24 amps.

Mr_D · 06-16-2018, 09:23 AM

Our '02 DSDP had two 13.5 heat pumps. Ran both of them on 30 amp regularly with no problems other than having to watch how much other stuff we tried to run.

Hikerdogs · 06-16-2018, 07:59 PM

We have 2 Coleman 13,500 btu Mach 8 air conditioners on our 2013 Winnebago Adventurer. The maximum draw in the cooling mode is 14.1 amps at startup. If you have similar AC units and stagger the startup you should be able to run both on a 30 amp service. We run both of ours regularly on a 30 amp service with no problems.

Some older units draw more at startup and when running, so I would say it depends on the age and model AC units you have.

RayChez1 · 06-16-2018, 09:14 PM

On my coach I can not run two air conditioners which are also heat/pumps with 30 amp. I need 50 amps. I would think you are taking a chance of burning up an electric motor.

scbwr · 06-17-2018, 05:15 AM

I'm a newbie to motorhomes, but I'm surprised that no one has mentioned energy management systems. Don't many motorhomes have energy management systems that control AC use to avoid problems? Therefore, it would depend on whether the OP's coach has an energy management system.
I'm certainly interested in hearing what experienced owners have to say about this.

Bloodyhell · 06-17-2018, 09:06 AM

The EMS in my coach tells me that my two A/C heat pump units use 24 amps together. The seasonal spot where we keep it when we’re not traveling has a 30 amp service and that really has very little effect on anything in practice. Occasionally it will shed the water heater or the refrigerator when we are using them with the microwave or the coffeemaker, but there is no real discernible effect. The campground has offered to upgrade our service, but we haven’t had them bother with it.

RayChez1 · 06-17-2018, 10:20 AM

It is true that some of these gasoline motor homes have smaller air conditioning units with smaller motors to save, they are called energy management systems. But most of your top end coaches have the heavier units and do require 50 amps.
You got to be careful when an electric motor is not getting enough amps, it will start to drag and eventually something has to give. Usually it will kick the circuit breaker, but at the same time it is causing damage to the motor.

JLWoodward · 06-21-2018, 06:28 AM

Ray. My class A coach will run on 30 amp. Ems refers to coach system that will shed other loads and not let both ac units start at same time if theirs not enough amps. Usually if I’m on 30 amp I run water heater and fridge off of the propane. The late model class A’s do have higher amp loads. Some have three ac’s. Floor radiant heat, etc, etc. not sure one of those could run off of 30 amp but in theory their load shed ems systems should all work in same way and protect system from overload by shedding loads to keep under 30 amp.

OLYLEN · 06-21-2018, 08:51 AM

Yes I did it all the time, BUT, watch the voltage. Problem is as more other RVs next to you use power many times the voltage drops. As voltage drops amp draw goes up and according to specs below 108 volts you run the risk of AC damage. I use a Kill-a-Watt volt meter to see voltage and have in the high use hot afternoon or evening run the Gen to have both AC's run.

LEN

Hit_the_Rhod · 06-21-2018, 08:59 AM

Quote:

Originally Posted by critterair2

Coach has 50A service but on our 5 week planned trip we have one CG that only has 30A service. We have 2 AC units 13,500 each. Hot water heater I can run off propane. Will 30A run both AC units at the sane time? Only other draw would be tv's. We can deal w/o microwave for one night if we need to or shut off one AC unit while micro is in use.

We have personally done exactly what you describe above on 30 amps with no issues, on multiple occasions. As stated, we will generally shut down one AC unit if using the microwave, or the coffee pot, but other than that, we've even run the water heater (accidentally) on electric at the same time and not had a problem. We have two 15k btu heat pumps.

Hope this helps!

Bob Hyatt · 06-21-2018, 01:40 PM

Quote:

Originally Posted by critterair2

Coach has 50A service but on our 5 week planned trip we have one CG that only has 30A service. We have 2 AC units 13,500 each. Hot water heater I can run off propane. Will 30A run both AC units at the sane time? Only other draw would be tv's. We can deal w/o microwave for one night if we need to or shut off one AC unit while micro is in use.

I was just in a CG with the same issue. 30A. I have a 13.5K BTU rear A/C and a 15.0K BTU front unit. We ran them both with no problems. But I can set the power system to tell it there is only 30a available and it will figure out what to do, except (apparently) when the electric option on the water heater kicks on and both of the A/Cs are running. But with the water heater on propane, we had zero problems with 2 A/Cs running + TVs, Lights (LEDs everywhere in coach) and such. Used the microwave a couple of times but can not say for sure what else was running or was shut off automatically. The WH tripped the 30a breaker once before I set it to propane only.

You should not have much of a problem, and it was pretty hot this past week in Central Alabama where we were...

critterair2 · 06-21-2018, 01:49 PM

Spoke with manufacturer, was hoping I could isolate the batteries so they wouldn't charge until I wanted them to. That way I could run lights and fridge off the batteries, hot water heater on propane and all 30A would run is tv's, AC units and microwave. Obviously I can load shed those 3 items as needed. May just run genny during hot part of day and one AC unit at night. May turn AC unit to like 55 degrees so it comes on and stays on instead of cycling.

JLWoodward · 06-22-2018, 07:52 AM

Quote:

Originally Posted by critterair2

Spoke with manufacturer, was hoping I could isolate the batteries so they wouldn't charge until I wanted them to. .

Seems like this should be possible via a switch controlled contactor installed on output of charger Line to batteries.

Bob Hyatt · 06-22-2018, 09:06 AM

Quote:

Originally Posted by critterair2

Spoke with manufacturer, was hoping I could isolate the batteries so they wouldn't charge until I wanted them to. That way I could run lights and fridge off the batteries, hot water heater on propane and all 30A would run is tv's, AC units and microwave. Obviously I can load shed those 3 items as needed. May just run genny during hot part of day and one AC unit at night. May turn AC unit to like 55 degrees so it comes on and stays on instead of cycling.

My EMS control panel lets me turn the charger off with the push of a button, although it is smart enough to figure out it can't run a heavy-duty bulk charge while two A/C units are running.