Forum Discussion

GOTRO's avatar
GOTRO
Explorer
May 31, 2016

Class C A/C

We currently own a 2003 Tiffin 37 ft Allegra Bay gas motorhome. We will be downsizing and are researching the class C 28/30 ft motorhomes. However, we noticed there is only one a/c on all size class c motorhomes. Has anyone had issues with one a/c? Camping in the south this may be a negative issue - interested in opinions.
  • j-d's avatar
    j-d
    Explorer II
    I'd say consider Heat, Humidity, Sun, and Slides.

    Our 31 does not have Slides, but we camp in Heat and Humidity, often with no Shade. Our 15000 non-ducted A/C can keep us comfortable. We have window film and keep the blinds closed in the heat of the day.

    The 15000 comes at an amperage price. On the hottest days, we can run A/C, naturally our converter/charger, and maybe one smaller appliance without tripping the 30A main breaker. Or the one at the pedestal. By small appliance, probably a coffee maker, but NOT our microwave.

    So, the amperage of the coach figures into this... Not many C's are 50A. Even if they are, are the sites you like, 50A?

    Last time I looked, there were "high efficiency" 13500 units but not 15000 from the Big Two (Coleman and Dometic). I hear the new "Australian" Atwoods aren't as hungry as the Big Two. From what I read, I would NOT specify or accept an Advent A/C.

    Our Coleman Mach will frost up on LOW Fan on humid days, so I can't endorse the lower speed option without reservation. Remember, A/C removes humidity. Has to, and if it didn't you wouldn't feel as comfortable. BUT!!! That removal takes away cooling. It takes a lot longer cool a coach full of hot, humid air than one full of air that's simply hot.
  • Many/most Cs are now outfitted with 15K BTU units. Could be a heat pump. Many of the new AC/HP units have lower power consumption than the older 12.5 units.

    Many of the C coaches are ducted so you can get by with a single unit as they distribute the air more efficiently.

    FWIW. Our Coleman Mach 8 (15+K BTU) cools our 24' View (2 slides) quickly and it maintains the coach in the 70s on a 95+F Texas summer day in the sun. There are three tips. Install clear heat resistant solar film to windows and windshield. Keep sunscreens/shades down on sunny side. (View has Remis style shades in the cab.) Set the AC fan speed on low so the air spends more time on the evap coil. This gets a couple more degrees colder and removes a bit more humidity. Optional to put it on RUN for full time circulation. That will continue to pull cold air off the evaporator for a few extra minutes untill the next compressor cycle.

    Note: technically....an RV unit will only produce cold air that is about 15 degrees colder at the duct than at the intake.
  • If outside temperature reaches 90,single AC may keep inside at75 if you have window shades down and block sun from coming in windshield and side windows.
    We have stopped camping in really hot Socal weather, rather be home with effective AC, hobby activity, TV etc. and all the comforts. Want to be outside under awning in daytime while camped.
  • We own a 32' Motorhome with 2 slides and find the single, 13,500 Btu A/C adequate. Ours is ducted. When it is above 90 degrees out, it does seem to run often.

    If you camp often in open areas with no shade, you will probably find your A/C running almost constantly, but it should be able to keep the camper cool.

    -Michael
  • We have a 31' Itasca with one A/C and use it all summer in Arizona. I think as long as it is the ducted type it will be fine. We look for shade when ever possible and have window awnings on every window too. Works OK for us. Does run a lot though! We had a friend whose RV cooled from only one place in the ceiling and it didn't work quite as well as ours.

    Dave
  • Had mine for about a year now. Most use is parked in the open at NASCAR tracks in the summer time.

    I find the one A/C adequate. It takes near to an hour to cool down after getting up above 90 without it on but otherwise it's fine......for me.