Why can't I run both a/c without breaker blowing?

[catstorman]

We love our 2005 Gulfstream Crescendo. We bought it and started full-timing in Dec of 2010. It had only 26,000 miles on it and in great shape. We had a of trouble with the engine and $12,000 later, Gulfstream finally decided there was a hair-line crack on the engine and replaced it, so now, we have an older RV, but a new engine and we have been quite happy with it EXCEPT:

Why can't we run both a/c with 50 amp service???? We seem to only be able to run the front air and if we try to run more than the Tv, it will blows the breaker. We have tried replacing the breaker and it solved problem for about a month and then went back to popping breaker when we would try to use front and back a/c. Why have 2 a/c if you can only use one??? I can't even run the tv and oven if the a/c is on? Any advice??? :cry: :?:

[GStream40]

If the Amperage load is not wired to distribute the load between the two 50 breakers then when you try to use the AC that is on the heavy loaded breaker it will trip.
In other words if the water heater, oven are both on one breaker along with the rear AC that is probably at max load, you turn one one more appliance like the TV, then that is over the 50 amp limit so the breaker will
trip.

What I would do is turn off the breaker that is always tripping, then find out what is off or won't run. I would then figure out how many amps are being pulled on the leg/breaker. I would then do the same for the other
50 amp breaker.

If the one leg breaker is much more loaded than the other, then I would change a heavy use appliance to the lighter loaded side to distribute the load more evenly and keep it below 50 amp on each leg/breaker.

I believe you will find that the one breaker has more heavy amp draw than the other.

One other thing that will cause breakers to trip is low voltage being supplied. Low voltage causes higher amp draw.

Hope this helps and I didn't confuse you.

Ron

[rdlamb]

Hi.
Ron has great ideas for you. Here are a couple more.
Your AC's require a "boost" of amps to start them. If your total starting amps even slightly exceed your allotted breaker amps pop goes that breaker.
First, make sure you have a full 50 amps delivered by shore power to your breaker box. Many parks advertise 50 amps, but have lines and equipment that provide a highly variable amperage to your coach. Breakers trip for many reasons, amperage being the one we focus upon. Drop the voltage to 102-5 volts and your amp demanding AC's will heat and trip your breakers.

Usually, only your AC's are on one breaker. Usually. Turn everything off and try running one AC, then add in the second.
Tripping the breaker in that case would lead me to question the circuit board in the AC.

Do you have electric appliances? Stove, refrigerator, perhaps an electric water heater, or an insta-hot?

There are excellent meters that measure how many watts are being used on each line, so you can get an idea where the trip came from.
Finally, did you install any new hangers, place any nails or screws in any area near the AC? Puncturing the insulation of your electrical line will trip breakers.
Also, do you have a generator? If so, can you run both AC's with generator power?
Rick