Cooling the back of the RV while driving

[randomguy]

When driving in these 90-100+ days, I pretty much have to run the generator full time to run the AC in the back to keep the MIL and kids cool. Not to mention the wine.

Is there a way to keep it cool back there without running the generator? We close all of the blinds, have tried the ceiling vent fan, crank the front AC up to 4 and point it straight down the middle.

I was thinking of getting driver/passenger fans, but those only would seem to benefit those up front. We tried a fan in the back and it helps if it isn't direct sun, or at about 85 degrees, but MIL starts complaining after that.

[Mr_D]

My rig has a second OTR air con unit under the bed. Not something very many MH's have.
Running the generator and air cons is accepted practice for most people.

[JohnBoyToo]

Don't even give it a second thought about running the generator !!!
It NEEDS to be run about monthly anyway to keep it from rusting up

and why sacrifice your (or your passengers) comfort for a 1/2 gallon of fuel per hour?

what we typically do, is once it's cool, we turn off the dash air, makes for a quieter ride and we can hear the audible book betta !

and even further, we set the roof air to a comfortable temp and turn the genny on and off with the dash switch for remote control since the DW is ALWAYS colder than me and so I got one of these too for me.

[JFXG]

I have read more than a couple of threads and articles arguing that it is actually more fuel efficient to run the generator with rooftop a/c units, rather than the dash a/c unit. The argument posed is that the engine mounted compressor supporting the dash a/c saps more HP- and thus fuel- from the engine than the generator burns to support the a/c units.

[super_rep]

When traveling if the outside temp is above 70DEG, our generator is always running and the roof top AC's are on. We want to be comfortable when we arrive. If you can afford the motorhome, you can afford to run the generator.

[GoneToTheDog]

Originally Posted by super_rep

When traveling if the outside temp is above 70DEG, our generator is always running and the roof top AC's are on. We want to be comfortable when we arrive. If you can afford the motorhome, you can afford to run the generator.

I totally agree.

[TripleGGG]

Originally Posted by super_rep

When traveling if the outside temp is above 70DEG, our generator is always running and the roof top AC's are on. We want to be comfortable when we arrive. If you can afford the motorhome, you can afford to run the generator.

X2 for us as well. Actually 68 on the temperature setting. [emoji300]

[nctox]

Hey! Let's get our priorities straight here. That wine has to stay cool.
Run the genny.

[LPerry]

I have considered adding a rear air setup or maybe an invertor big enough to run the roof ac off the house batteries for a while. Our propane generator means that on long driving trips with boondock destinations (rally races usually), we challenge our propane tank size after a while. The genny is so lightly loaded nearly all the time that it seems like an invertor and high capacity dc charger (from Genny) might be the better way to go in general anyway. I've considered adding a second alternator just for keeping up with the house batteries in such a situation.

[Crasher]

Start the morning with the genny running and the AC's on. Keep the interior cool all day. Once you let the furniture and rest of the interior warm up, it takes that much longer to cool everything down. We have found that by running all three roof ACs and turning the dash AC off, we can keep the entire coach uniformly cool by running the windshield fans to circulate. The roof ACs cycle on and off during the day.

[Mr_D]

Originally Posted by LPerry

I have considered adding a rear air setup or maybe an invertor big enough to run the roof ac off the house batteries for a while. Our propane generator means that on long driving trips with boondock destinations (rally races usually), we challenge our propane tank size after a while. The genny is so lightly loaded nearly all the time that it seems like an invertor and high capacity dc charger (from Genny) might be the better way to go in general anyway. I've considered adding a second alternator just for keeping up with the house batteries in such a situation.

A second 3000 watt inverter, a larger alternator and two more 8D AGM's to run the front heat pump OTR was a listed option for my rig but it doesn't have it. Would be nice to have though.

[Mr_D]

Originally Posted by JFXG

I have read more than a couple of threads and articles arguing that it is actually more fuel efficient to run the generator with rooftop a/c units, rather than the dash a/c unit. The argument posed is that the engine mounted compressor supporting the dash a/c saps more HP- and thus fuel- from the engine than the generator burns to support the a/c units.

I've seen the same thing but no definitive testing that I've found.

[redcolorado]

We live in central Texas and go to Corpus Christi fishing 4 times a year. We have found the fuel economy is about the same running the dash air or running the generator and the air conditioners. As a previous poster said keeping the coach cool is a lot easier the cooling it down when it gets hot. We start the generator when we leave home and shut it off at the campground when we get back on shore power. Didn't we spend all that money on these rigs to be comfortable? I did.

[Kro1957]

Since we have had the Motorhome we just ran into our first bout of hot weather on the road. It was in the 100's and we had to travel back to South Dakota mid July. Not knowing the right/wrong, I really did not care in that extreme heat, I had that Onan run with both AC's on High. Kept the coach nice and comfortable our entire trip and I did not notice hardly a difference at all in any diesel mileage. The only thing was we racked up some more hours on the Generator. Here's to life in the RV..... lovin it...