30 amp with a/c units?

Couple of things:

1) my 5th wheel is wired for 50A but does not have an EMS.

2) turn the converter off before you attempt to run two ACs - it can draw a lot.

3) if your THERMOSTAT is like mine, it will not start both ACs at the same time - there is a time lag of about 30 seconds. No need to set different temperatures.

4) right now my rig is on a weak 15A circuit which will not run even one AC. In a couple of days I'm going to move my rig to where I can plug into 30A. I'll try the two AC test then and let you know.

5) I guess this is more than a couple of things.

Sober person posts---Can I get drunk and drive? Alcoholics respond, SURE, we do it all the time and nothing bad ever happens. Sober person then thinks, great, I can do it also. To the posters that stated yes you can run 2 AC's on 30 amp. YOU have no skin in the game. The correct answer is MAYBE! It all depends on how his RV is wired and if the RV allowed 2 AC units to run on 30 amp. MOST 30 amp RV's do NOT allow 2 AC units to be wired on 30 amp(unless there is an EMS system) Most Towables do not have an EMS system. It depends on the AMP draw of the 2 AC units and IF YOU HAVE AN EMS SYSTEM. It depends on the outside Temps. HIGHER temps will pull MORE amps. So, lets take this example. You are in 80 degree temps. Your AC's pull 13 amps at 95 degrees(spec). At 80 degrees those AC's will only draw 11.5 each for a total of 22 amps. You think great I can run 2 AC units on 30 amp. Lets now go to 100 degree. Those 2 AC units will now draw 13.5 each for a total of 27 amps. Add anything else and you go over the 30 amp threshold. Now, the Breaker will trip? MAYBE. What usually happens is, the line voltage drops and the wiring heats up. LOOK at the 30 amp shore cord end. WHY do they seem to look burnt and corroded/pitted? Because you have been overloading the power supply. Some CG's may have larger than 30 amp breakers on that 30 amp supply. Then add in the fact that most that run 2 AC's on 30 amp use a 50 to 30 amp dogbone adapter. IMO, DO NOT ADVISE PEOPLE TO RUN 2 AC UNITS IF YOU HAVE NO KNOWLEDGE OF THE SYSTEM THEY HAVE. Doug

Turn fridge and water to propane only and give it a go.
Nothing will be harmed to try once. Use low fan speed.
Microwave or hair dryer will trip breaker so don't.

Get an autoformer to support low voltage that running both may cause. That may allow you to run both air units at the same time.

delete... (double post)

One additional hint. To insure that both units do not start at the same time (which draws extra power) turn the thermostat on the primary unit down really low so it is in continuous run mode. Then use the second unit to control the actual indoor temperature.

I'm on 30 amps running two a/cs. Never know till you try. Keep a watch on them, may just run fan on 2nd ac. Can't run anything else with 120v, put frig and WH on LP. Should blow breaker at pedestal if too much draw. If it does blow turn off AC and flip. Breaker back on.

Turn everything off that is not necessary. Then turn on both air-conditioners. If they run, then your answer is "yes". If the breaker pops, either the one inside your camper or the one at the power pedistal, then the answer is no. The worth that will happen when you turn both on is, the breaker will pop. Nothing hurt. Turn one air conditioner back off, and reset the breaker. Then you'll know.

turbopilot51 wrote:
Can we run both a/c units (15 &13.5) on 30 power? It is 100 degres where we're at and one a/c is barely keeping up.

you likely can IF your RV has an energy mgmt system. an EMS will start shutting down unneeded loads such as the fridge and electric water heater in favor of the AC. if no energy mgmt system then....

- if you're in a MH go to home depot, lowes, ace, etc and get a roll of window foil and use it to block the windshield. 99% of the heat is coming thru there. the windshield heats up and radiates heat into the RV.

- bring in the slides. less sq feet means the AC wont have to work as hard

- get a couple of fans to help move the air around

- run the fridge and water htr on gas to reduce your elec load to help the AC keep up.

- go out to a movie or shopping center during the hottest part of the day

- lastly, pack up and go elsewhere. you're in an RV after all.

I can run both of mine on 30 amp.