Adding an Air conditioner...as in a third?

OK....so I have two older Carrier 15000 BTU units on my Vogue, these two replaced two Coleman 13,500 units that were standard equip. My front Carrier just doesn't have the output anymore and "ices" fairly easily, ( I keep the fin's and filters clean, I think it's more the fan speed has diminished). When the two units were working flawlessly, in a stationary position, I could actually get it "Cold" inside during extremely hot days...over 110 degree's, but while driving in such weather, very difficult to cool the driving compartment. (Dash air on my MH has been looked at but for the price of replacing the whole "old" system, it's less expensive to go with roof air...that's a whole different conversation).

Anyways back to my question....has anyone here actually put in a third roof air where no provision has been made for such. I'm not one of those who is frightened by cutting holes in my fiberglass roof and I do have an empty 20 amp breaker in my MH panel. the Carriers and Coleman unit were in the 100+/- pound category, the Brish Airs II are about 74 pounds. I walk on my roof all the time and I'm 250 lbs so weight bearing shouldn't be an issue.

I know this is getting long winded but my thought is to replace my front Carrier(the one at issue) with either a Coleman or Brisk Air 15000 BTU unit and then add the third Brisk Air forward of the other one so to offer more cooling up front while driving and for those really Hot days while stationary. As stated, not worried about how to wire it or worried about cutting into it other than hitting some type of super structure in the roof(steel framing). If it becomes evident this isn't an option, I'm sure I'll be OK with just a well functioning replacement....so let me have your thoughts.

PS...I have at times used a portable air to supplement cooling during those times when the roof unit in question has preformed poorly.) Thanks all for reading my Novel...LOL

BarneyS
Explorer III
Feb 27, 2016
Acampingwewillgo wrote:
Interesting Chris....so can I assume you prefer the Atwood brand over all the rest?

On edit:
I read about the Atwood's a couple year's ago..namely the estimated 18,000 BTU output for the 15k models. I like the two motor idea so that the condenser fan runs at high speed always which in my mind, might prevent those darn freeze up's. The unit weight looks good too at 84 lbs. and the price seems in line with other units. I also like the 3 speed blower....
Best prices that I've seen so far is at the 12 volt store? Unless someone has a less expensive location???? :)

Thanks Chris

I replaced my 11 year old Dometic unit with the Atwood Air Command last year. It is very quiet and puts out a lot of air or heat. We have been very pleased with it. Best price I have been able to find now is at PPL motorhomes parts.
Barney
Acampingwewillg
Explorer II
Feb 27, 2016
Hornnumb2 wrote:
You said the 2 worked fine in the beginning, why not just replace the bad unit.

No...I said when they both worked, it was Great but the last couple of year's the front hasn't worked so well. I should emphasize that a lot of my RV'ing is done in HOT to very Hot climates. We live in So Cal and many trips are to places such as Nevada deserts, Calif summer climates etc etc.. The fact is that when stationary, having two well working units were enough BUT while traveling down the road in hot weather with that huge windshield and the hot air blowing straight at the front facing area of the MH, keeping the cockpit, even cool, was an issue since my dash air does not function.

The idea of a third unit was two fold....extra cooling while stationary, when necessary and having the third unit forward enough(nearer the driving compartment) might help some while driving. This is just to clarify......I'm pretty much sold on the idea right now to just replace the marginal unit! :)
jjrbus
Explorer
Feb 27, 2016
A 13 year old AC! I would not be upset about replacing it.

I did read somewhere that the mini split outside unit could be installed flat. Don't take my word for it, might vary from co to co? There is a minimum distance from rear of unit to wall. My bugaboo on it was the inside unit should be mounted 6" from ceiling and I have no place to do it without losing half my cabinets.

These new Advent AC's might be worth looking at. Jim
Hornnumb2
Explorer
Feb 26, 2016
You said the 2 worked fine in the beginning, why not just replace the bad unit.
Acampingwewillg
Explorer II
Feb 26, 2016
Interesting Chris....so can I assume you prefer the Atwood brand over all the rest?

On edit:
I read about the Atwood's a couple year's ago..namely the estimated 18,000 BTU output for the 15k models. I like the two motor idea so that the condenser fan runs at high speed always which in my mind, might prevent those darn freeze up's. The unit weight looks good too at 84 lbs. and the price seems in line with other units. I also like the 3 speed blower....
Best prices that I've seen so far is at the 12 volt store? Unless someone has a less expensive location???? :)

Thanks Chris
Chris_Bryant
Explorer II
Feb 26, 2016
Replace the front Carrier with an Atwood, problem solved.
Acampingwewillg
Explorer II
Feb 26, 2016
I just did another look at Mini split systems.....this would work great with two possible problems: one would be whether the condensing unit could be installed on the roof in a flat format...sort of like a solar panel mount allowing air under the unit. Secondly, I wonder how they hold up to vibration?
Acampingwewillg
Explorer II
Feb 26, 2016
In the year's I've owned the MH(about 13), I've been on and off the roof many-many times checking, cleaning and such with the air conditioners so I'm fairly familiar with the operation but with what you have added, I may take the Carrier off the MH and do a complete hose down of the coils and fins and then bench test it before dragging back on top. 10,000 watt generator so no problem there and it is a 50amp MH...I've dabbled with elect work my whole life, so no issue there either. I have looked at the mini split systems and they are an option..I may look some more. I have until July(trip to Texas) to make this happen one way or another.

Thank's Eric.......
jjrbus
Explorer
Feb 26, 2016
Hmmmm. I have seen a perfectly good roof air replaced because the evaporator was plugged! I know you said you clean and check, before spending a bunch of money I would pull the cover and look at the evaporator and condensor. Just costs time.

You do not mention if they are ducted, some ducted units are so poorly designed it is amazing they work at all! If ducted try to pull the covers and run without them and see if it makes a difference.

Great big windows heading into sun, very hard to beat, the best I ever did was curtain off the driver area and use dash air or a large fan, circulating the air. Large fan without the curtain of course.

Mini splits, my dream, I calculated every way I could to put a mini in my current Toy and cannot figure it in.

Not sure if 3 15K roof airs can be run on a 50 amp service or your genset, need an electrical person for that. I can figure it out but would take me an hour or 2 or 3.

Only my opinion, not to be misconstrued as knowledge or professional advice. Jim
96Bounder30E
Explorer II
Feb 26, 2016
Dwight... The only issues I see is... Getting wiring to the 14" x 14" cutout....and to the breaker box....

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Adding an Air conditioner...as in a third?

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