Too hot for any RV Air conditioner ? - Montana Owners Club

G McCall · 07-01-2009, 09:19 AM

For all campers, 109° is too hot

My story is for others to compare and learn.

We arrived at our trailer located at our country getaway last Friday about 7:30 in the evening and found the trailer main breaker had tripped. We had been leaving Frig on and the AC on with the thermostat set at 90°.
Apparently if the temperature is going to get too hot and the breaker starts too heat up, starting at 90°, the breakers will trip under the extreme heat conditions.
The temperature of the Frig and indide the trailer was hot when we got there ! The inside temperature was/had been 111° and of course, the trailer was unbearable to be inside for a while. We got the breakers on again and the trailer finally cooled down in the middle of the night. I ran Frig on gas and that worked well enough.

THEN......by late afternoon last Saturday, two outdoor thermometers read 109 in the shade. The inside temperature of our trailer reached 86° with the AC still blowing cold air. We even had 2 granddaughters with us. At about 4:30pm , the AC breaker tripped again. Apparently the breaker setup can not handle the Amps we were pulling. We had two TVs going, two fans, the kids were playing WEI etc. I think one of the problems was that the inside of the trailer got warm and allowed the breaker itself to get warmer than usual. Anyway, it was so hot, that we decided to go to town and eat dinner, and on the way to town we decided to pack up and go home when we got back. We did get the AC back on before we headed to town and the trailer was cool enough when we got back, but the forecast for Sunday was "hot" and we had suffered through all the heat we wanted.

The problem with the heat and sun is that the trailer sits in the sun in the middle of the day. At my deer lease we never had that problem with the trailer under a big tree and a RV topper. Of course the 109° might have still caused problems, but IMO the trailer needs to be in the shade in the Texas summers.

Glenn and Lorraine · 07-01-2009, 10:00 AM

Or maybe a second AC. I find on a hot humid day here in Florida running both A/Cs make a world of difference. On some hot days the livingromm A/C, by itself, could barely get the temp below 82.

Was it the Monty's breaker or the CG's breaker that tripped?

stiles watson · 07-01-2009, 10:26 AM

Yep, it is hot in Texas. My brother-in-law emailed us to stay in Washington. He said it is way too hot in central Texas. The high here in Chimacum, WA is scheduled to be 72°. I think I will take his advice.

azleflyer · 07-01-2009, 12:59 PM

We've been running both a/c units because of the extreme heat. The breaker did trip once Monday on the main unit but I am not sure what may have caused it. Have not had any problems since. Maybe a weak breaker? Heading to Mobile, Alabama and I hear it it very hot there as well. We'll see how it holds up there compared to the Texas heat.

sreigle · 07-01-2009, 01:06 PM

When we had a single AC, it would reduce outside temperature by 12 degrees max. With two AC units and outside temperatures of 102 we were at 73 inside, right where the thermostat was set. If you don't have 50 amp service then this is not a solution for you. I don't know what's causing your breaker problem. Sorry I can't help with that.

robb · 07-01-2009, 01:34 PM

Did you check the voltage when the breaker was triping? Low voltage will cause the amps to go up and trip out the breaker!

2007 3400RL
1999 Volvo pickup
2008 Smart car

Art-n-Marge · 07-01-2009, 02:26 PM

When it's that hot, and everyone is maxing out their AC, that might cause a draw on the CG for a brownout, but would that cause a breaker to trip? I would think the breaker would not trip and the brownout could actually damage anything with a motor (AC, Fridge, Microwave). That's worse than a breaker tripping isn't it?

If the breaker might trip on temp maybe you could also set up a fan aimed at the converter (or whatever it's called). Could that help? Electrically speaking a breaker trips on too much amps. Do amps go up on a brownout?I forget.

Someone call an electrician or an AC guy.

HughM · 07-01-2009, 02:53 PM

Once while traveling thru Hot Springs, Ark. (note the name of the town) the bank temp said 109. We had a class c with one air and a generator which was running so we could run the a/c. The temp inside the r/v was so bad we pulled over and called Coleman to see what was wrong with the a/c. They told us 10-15 degrees was the best we could hope for.
We pulled into a campground and asked for a shady campsite and got one. Sometime after midnight it finally got down to 80 degrees.
That was my last 30 amp camper with one a/c.
Never blew a breaker but I'm sure it was hot.
Hugh

ols1932 · 07-01-2009, 03:00 PM

Interesting posts. Our experience living in Desert Hot Springs, CA from January 2008 to April 2009 (15 months) showed us that even with the temperature reaching 118° on the hottest day last summer, we were well able to survive without a lot of discomfort. I'm sure that if we had a 2nd AC installed that we might have been able to drop the inside temp below 90°. As it was, we were in the mid 90s and used our 12-volt silent breeze fan (by Fantastic Vent Co.) to circulate the cool air from the AC with it (the AC) set to "Quick Cool."

So, I'm one to say that what is too hot for one may not be for another. When the temp gets high, it's hot even in a stick house. At least it was in ours.

Orv

guru1961 · 07-01-2009, 03:32 PM

Wife and I are in Devine...40 miles south of San Antonio...and it is HOT!! Montana a/c breaker tripped yesterday while we were at work and upon returning after 4pm to trailer it was 99 inside. It was 102 in shaded area we have parked. It took several hours into the night before the living area was cool again. Used our second a/c in bedroom to cool that area for sleeping. Our panelboard is in the restroom area and we left the door closed with no ventilation to this area so it got warm during the day and helped with the breaker trip. Today we left the fantastic vent (replaced the little fan in there awhile back) blowing in there and no problem with the a/c. We left the bedroom a/c on as well today and it was 81 in 'Tana when we got home this afternoon and temps was 99. We installed sunshades over the windows on the slide right and rear windows. It is going to be a long summer here!! Not sure how to get any cooler without spending more $$!

Trailer Trash 2 · 07-01-2009, 04:55 PM

Hot is Hot and 3 digits is head home time for me.

But just a quickie Q, do you run the frig and water heater on propane while in the heat? it should cut down on the power usage and direct all the voltage to the most inportant item AIR, thats what I did while in Airazona when it was 3 numbers on the thermomitor it did seem to help my bigist problem ofr me is iceing up, and when I leave the dog in the RV I always worry about the air conditioner, my next project on the monty is to find a reliable airconditioner and take that unreliable Dometic unit off the roof.

NCFischers · 07-02-2009, 12:58 AM

Art,
In a brownout, less volts = more amps.

richfaa · 07-02-2009, 05:06 AM

We have never been in that kind of heat with the 3400 and hope we never will be. For us the A/C set at 80 is good as long as it wrings the humidity out of the air. We had a 90 + day with very high humidity here along the Great Lakes last week and only those who live along the G.L's can related to what that means. We had both A/C units running in the 3400 while we were loading for a trip and they worked hard to keep it at 80. Same with the whole house A/C in the stick house. These campers do not have the insulation for that kind of heat not to mention the drafts. Nope..We have lots of time and the camper has wheels...we can choose our climate.

thor · 07-02-2009, 04:15 PM

when we are at work in the summer they open the electrical panels at work because the heat kicks the breakers out sounds like the same problem to me.put a fan on the breaker box see if that helps

harleyrider · 07-02-2009, 09:05 PM

With all this talk about hot weather,and me heading to florida in October.I`am thinking a second AC might be in order.At present I have a fantastic fan in the bed room.Mines a 50 amp.But i`am not sure if its wired for a 2nd AC.I do know at the breaker panel theirs a tag that says "for 2nd AC"with no breaker in that slot.I have heard if its not wired the install can get pricey.Any thoughts????

richfaa · 07-03-2009, 03:32 AM

harleyrider...October in Floria is OK. We are there from Oct to April and the weather is moderate. IMO unless you are in very hot or humid weather on a regular basis two A/C are not required.We do have two A/C and we seldom use both of them at the same time. Two are a nice to have but not a need to have option......IMO.

sreigle · 07-03-2009, 04:20 AM

I agree with Rich. We got along just fine on one AC for a number of years. But we always left the KC area by the end of July every year, after granddaughter birthdays. We had a few days in July and sometimes June where it was warmer in the rig than we'd like but not unbearable, with additional fans running.

The second AC makes a huge difference, however, if you are going to spend significant time in hot weather. If we hadn't decided to do that we would not have added the second AC last Fall. This June was a scorcher in KC and those days we were without the second AC (AC failure) were miserable with temperatures hitting 90 inside the Montana.

But, if we had not decided to spend more of the summer in KC, we'd not have added the second AC.

Trailer Trash 2 · 07-03-2009, 04:40 AM

I think adding a aditional air conditioner has to many other factors to include and one is the service in the RV is it big enugh to havdle an aditional air? a 30 amp service will involve a change to a 50 amp service and pulling aditional wire for the air if it wasn't preped for it, but most of the bigger RV are set with a 50 amp service mine wasnt it came with a 30. so 1 air fo me.

G McCall · 07-13-2009, 08:52 AM

Trailer AC not cooling solved !

I had an RV carport built over my trailer and the cooling result inside my trailer is obvious.

Last Saturday, the outside temperature was 100° and my inside trailer temperature was 74° and holding per the thermostat setting. The unit was even cycling on automatic. About 4 pm the outside temp reached 102° and the inside temperature was holding between 75° and 76° with the AC unit running continusly. I could have closed the bedroom off and moved the air control to the living area of the trailer, but it was not necessary. Shade was the answer. ALSO the AC breaker stayed cool and of course did not trip as it had done in the past.

Tom S. · 07-13-2009, 09:22 AM

When we ordered our Monty, being the frugal (cheap) person I am, we ordered it with just one air conditioner, located over the rear of the trailer in the living room area. But we had the foresight to order the trailer wired for a second ac unit, and we were glad we did. The first time we took it out we encountered 90 degree / 95 percent humidity and the single unit was really struggling. When we took the trailer back for some warranty stuff, we had the second unit added in the front (bedroom area). It has turned out to have two benefits. Besides keeping the trailer much cooler, the design lets us point the output air straight through to trailer, which lets us run the rear unit a lot less. Since the rear unit is also where the TV is, running the front air makes listening to the TV a lot easier!

I learned my lesson. Since you never know what kind of weather you're going to encounter, I now recommend anyone ordering a new trailer get the second ac unit. Kind of like what many gun owners say: it's better to have it and not need it than to need it and not have it, at least to me.

You may also like: