Portable Air Conditioner Question

[edmck101]

Looks like I need to stay in Tucson next summer in a 36-foot Bighorn 5th wheel. I'm fine with that — I like Tucson until the temperatures start to climb. By September they can reach 110 degrees nearly every day. Meanwhile, my rig has two 15,000 BTU roof air units that I know (from experience) will keep the coach cool until it's 105 outside. Anticipating this problem, I'm considering the idea of a portable indoor air conditioner. Some that I've seen at Amazon get great reviews, and the $500 - $600 cost is reasonable considering the problem. Just wondering if any of you guys have experience using a portable AC unit in a motorhome or trailer. Thanks for the help.

[pasdad1]

Be sure to get a dual hose model. One hose sucks in outside air to cool the condenser and the hot air goes out the other hose. If you get the single hose model, it sucks your inside cool air to cool the condenser....this creates negative pressure in the rig, and pulls in hot outside air from anywhere it can....not good.

Dual hose models cost more and are not as common.....just keep looking till you find one

[Cat]

Originally Posted by pasdad1

Be sure to get a dual hose model. One hose sucks in outside air to cool the condenser and the hot air goes out the other hose. If you get the single hose model, it sucks your inside cool air to cool the condenser....this creates negative pressure in the rig, and pulls in hot outside air from anywhere it can....not good.

Dual hose models cost more and are not as common.....just keep looking till you find one

Absolutely, true "two" hose. Thats what we we used in our MH while in Tucson the last several years before I retired. It worked very well. I had window awnings on all windows, front windshield coverings and put my side awning out and still couldn't stay cool in the summer--until I bought the portable a/c. Safe Travels

I saw that they also are now selling a portable split air conditioner. The split A/c are usually very efficient. I would have bought that if they had those had been available 5+ years ago. Good luck

[Ray,IN]

Adding insulation to all windows and skylights will do much more than one would expect. naturally this means you need to use the lights during the day though. Is there any way to erect a temporary carport over your RV?
We once had a roll-around air conditioner with 2 hoses here in the house. The problem was the window panel with the two hose openings allowed so much heat transfer it was noticeably warmer standing by that portable A/C unit than in the middle of the room.

[WagonMaster]

I had one installed in my old Hitchhiker. It slid in under a desk area in the slideout. I cut a vent hole through the floor and when you slid it in you couldn't see the hose. Worked great. I had the single hose one and I didn't notice any negative pressure. It was quiet and cooled the living area quite nicely. If I were going to install another AC I would look closely at the mini-split systems. Where there's a will there's a way to install one of those things.

[edmck101]

Thank you for these suggestions and comments, they are very helpful.

[wiredgeorge]

Originally Posted by edmck101

Thank you for these suggestions and comments, they are very helpful.

We have 30A service in our small 5th wheel and when camping in triple digits in S. TX use a 14K BTU portable plugged into an 8 ga. extension cord run through the window to a campground pedestal. I don't recommend smaller portables as we started with an 8K BTU unit and it wasn't as effective. A portable doesn't provide as much cooling as a window unit in a home of similar BTU. We also have 80 percent dark tint on our windows to stop UVs and I have sealed up our ductwork so there is minimal loss into the void. The portable is run in conjunction with a new Dometic 15K BTU Brisk II roof A/C. Temps in S. TX in mid summer (triple digits) are in the 70s in the cabin. I also run an oscillating pedestal fan to move the air around. I used the original plastic part that fits the window for the exhaust and cut some plywood and use foam insulation set in the window for the A/C exhaust as our windows are arced in the corners.

[twinboat]

You really don't notice negetive pressure on the single hose ACs, but if its blowing air out, its drawing un-conditioned ( hot ) air in somewhere.
Around the door, steering shaft boot, poor fitting windows, holes for cables......

In a well sealed RV, it just won't flow enough to air out to remove the heat.

[Dutch Star Don]

If they'll allow it, you can also use a window unit. Years ago in my younger/poorer days, I use to remove my Lance Camper and place a window unit in the front pass thru opening that allowed you to crawl into the cab of the truck.

If you have a window opening large enough on a side where it won't be obvious (also in the shade) you could make a quick wood frame to support the unit. You could also plug it directly into the pedestal and not run through the trailer's system.

[wiredgeorge]

Originally Posted by twinboat

You really don't notice negetive pressure on the single hose ACs, but if its blowing air out, its drawing un-conditioned ( hot ) air in somewhere.
Around the door, steering shaft boot, poor fitting windows, holes for cables......

In a well sealed RV, it just won't flow enough to air out to remove the heat.

In my fifth wheel, this is NOT the case and I actually use a portable quite successfully. Is this something you read or heard from someone else? Just curious. Cable holes? Steering shaft boot? Poor fitting windows? Not sure what a Thor Axis is but I am pretty sure it isn't a 5th wheel which the OP has and I kind of doubt you see temps like I do or the OP will in AZ.

[twinboat]

Originally Posted by wiredgeorge

In my fifth wheel, this is NOT the case and I actually use a portable quite successfully. Is this something you read or heard from someone else? Just curious. Cable holes? Steering shaft boot? Poor fitting windows? Not sure what a Thor Axis is but I am pretty sure it isn't a 5th wheel which the OP has and I kind of doubt you see temps like I do or the OP will in AZ.

I didn't say they wouldn't work, its that they are less effecent then a two hose type.

Its science, if air is being removed from a space, that space develops a negetive pressure, or air is being drawn in from somewhere.

[jcussen]

My coach is pretty well sealed and I started off with a single hose which just draws interior air across condenser and blows it out the hose in the window. Noticed when sitting on the couch across from the door, that when someone opened the door, could feel the hot outside air being drawn in.
Changed to a dual hose and didn't notice that anymore.

[wiredgeorge]

Originally Posted by jcussen

My coach is pretty well sealed and I started off with a single hose which just draws interior air across condenser and blows it out the hose in the window. Noticed when sitting on the couch across from the door, that when someone opened the door, could feel the hot outside air being drawn in.
Changed to a dual hose and didn't notice that anymore.

Makes sense if you are sitting in the cabin in triple digit temps and the door opens constantly. Most folks that don't camp with kids don't have a lot of door traffic. My 14K BTU A/C works well for us. Could have easily bought the two hose type.

[jcussen]

Originally Posted by wiredgeorge

Makes sense if you are sitting in the cabin in triple digit temps and the door opens constantly. Most folks that don't camp with kids don't have a lot of door traffic. My 14K BTU A/C works well for us. Could have easily bought the two hose type.

Yes that is the problem with camping with kids. When they are indoors, they want to go outdoors. When they are outdoors, they want to come inside.