As we tend to spend summers in the Desert due to work commitments, keeping cool has become a priority for us. I resealed the roof and gave it several coats of elastomeric, I have interior and exterior blinds for the windshield etc and have serviced the roof ACs. However when it starts to get north of 105F everything struggles to keep up.I contemplated installing a 3rd AC unit on the roof, using the existing hole for the kitchen fantastic fan, but couldn't find an easy way to run cables without tearing out half the ceiling.As we had already pulled out the old couch and installed a large chair and ottoman, I had space in the front of the slideout for a portable ac. After a lot of research I found a dual hose portable 11000 btu AC with a very low noise levelWhynter 11,000 BTU Portable Air Conditioner ARC-110WD from www.sylvane.com with free shipping and a memorial day sale - total $430.I discovered that you have to use a dual hose system in an RV so that it sucks air in from outside to cool the condenser and then exhausts it - a single hose system takes air from the room to do that and that sucks in hot air from outside defeating the purpose of it!Below are some photos of the install - it was very easy - I did buy a 4" hole cutter from Home Depot to make a neater job. Everything was sealed with Dicor and there are covers that fit on the outside vents when not being used. It can also be removed from the RV in winter although there are some that act as a heater too (not this one).The first time I tested it, we noticed it was so much quieter than the roof air even on full blast and whereas the roof air had problems getting below 87 at 4pm, by switching this on as well, we could 'dial a temperature' - it got down to 72F within an hour and DW is looking for her coat!Well worth the money!! Bring it on Desert summer!

Nice... I bet that made you nervous cutting holes in your slide!!

What is your electric source? Did you use an existing outlet? 9.5 amps seems easy enough to manage.

Yes, I was a little nervous but I did what my Dad told me - measure twice, cut once :) I also invested in a 4" hole cutter designed for can lights - made short work of it but when the guide bit went through the fiberglass, I went outside and cut from outside in.It runs off the normal 15a outlet - I just have to remind DW not to run the tea kettle at the same time as it pops the circuit breaker. I added a battery backup unit for her computer (iMac) so that it doesn't cause any problems if she forgets :)

Nice way to work around a problem. Do you have any concern with critters getting into the unit thru the in/out grate openings?

Not really. When the unit isn't being used, there are solid caps that clip on to cover them. Either in the winter or when travelling.

Adding a 3rd AC | Good Sam Community

SomedayisNow
Explorer
Aug 10, 2013
We love our Alfa but it has minimal insulation. The 2 belly unit AC's have never cooled properly although they heat well. We added a 13500BTU AC to the roof, but that still was not enough in the south Texas RGV summer heat. We added a portable unit at the rear of the 5ver. We still hit low 80's around 4pm inside but by 6pm we are back down to the mid 70's inside. Planing to add an additional awning on the West side wich gets full sun in the afternoon. Every little bit helps.
antiquedrose
Explorer
Aug 09, 2013
Thank you so much for this comprensive and helpful post.

My daughter is living in AK and the nights were hot recently so we've been looking into portable AC's. We appreciate your effort and work!
chester490
Explorer
Aug 09, 2013
Thanks for the information.
havasu
Explorer
Aug 09, 2013
No, it still needs at least 1 roof air in the front to bring the temps down if you are over 100F - when the temps are down it can maintain a fair temperature.

In your case it should mean that you can use just 1 roof air and the portable, rather than both roof airs. Thus preventing the problems with the breaker.
chester490
Explorer
Aug 09, 2013
On it's own, does it cool as well as the 2 roof airs?
havasu
Explorer
Aug 08, 2013
I can use with the roof ACs or on it's own - plugs into the standard 15a circuit (actually pulls about 9amps). If you have a decent extension cord you could run it direct from the pedestal. (cable out of the window)

When it gets above 100F it makes life so much more bearable and allows the roof airs to cycle too.

DO NOT buy one that only has a single hose tho - it won't work in the RV.
chester490
Explorer
Aug 08, 2013
I am trying to clearly understand all that you are telling us. I am thinking about doing the same thing. Do you still use your roof air with this unit or do you only use this unit? Does it cool your entire rv? How many amps does it pull? Also, could you have run a cord directly to the plug in without running it through your rv? Thanks. We are in Houston right now and about 4pm we are burning up. The humidity is worse than the heat, it is awful. My air conditioners keep blowing the circuit.
havasu
Explorer
Jul 10, 2013
It plugs into a standard outlet - just be aware what else is on the same circuit. DW has a habit of forgetting and puts the coffee machine, or her Ninja cooker on at the same time and it flips the circuit breaker. I make her go and reset it now and she's getting the idea ;)

The unit I purchased uses the condensate to cool the evaporator and then ejects it as vapor out the exhaust so haven't noticed any issues so far. It has an auto switch if the storage tank fills up and then there is a drain plug - just not needed it so far.
skipndebbie
Explorer
Jul 07, 2013
Havasu,

we just bought a TH that we're having problems cooling the back room (garage) even thought the unit already has 2 a/c's and has vents in the garage. We are considering installing a portable unit for the garage like what you have in your pics.
what are you using for the power source? is condensation a problem?
havasu
Explorer
Jun 27, 2013
aarond76 wrote:
This looks good. I think I would add exterior dryer vents over the openings on the outside. I believe it would look more factory that way.

Ahh, you fell into the same trap I did.... I forgot that one sucks and one blows. Anyone need a spare dryer vent??

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