Follow up on Portable AC unit

[ALANSD]

As mentioned elsewhere, I do not have or desire a roof air on my Overlander.
In the Deep South it gets so hot in Summer we normally don't camp much if at all. When my 19 year old dog is no longer with us, we might. But he can't handle the heat.
I had a window unit in the front for a few years, it cooled ok but blew air across the gaucho and made sitting there uncomfortable.
We bought a nice 10,000 btu Hisense portable unit. I added a plexiglass window where the bathroom screen sits, and cut a vent hole in it.
The unit sits in the bathtub and drains right out.
We took our first trip in the July heat this past weekend.

The unit cooled the trailer on a 92 degree day, parked in direct sun. I booked a shaded site, but that's another story.
The inside temp after about 2 1/2 hours was 84. Evening temp was about 78 inside, and got to 70 by morning.
Very quiet running.
After reading that most Airstreams can be cooled to ten degrees under outside temps, I guess I should be happy with the results.
But was hoping for more cooling.
Maybe if moved out into the living area, it would have improved but the venting and draining would be difficult.

Bottom line still not camping in Summer in Georgia. If temps were mid 80s the unit would be sufficient.

[uncle_bob]

Hi

Humidity has a *lot* to do with how well an AC works. 90% RH is not even close to the same thing as 10% RH when it comes to cooling. Since people rarely include that data point, comparing your case to theirs is often difficult. Toss in things like shade, breeze, awnings, and orientation relative to the sun .... lots and lots of variables.

Bob

[xrvr]

Using a fan to help circulate the cool air may help.

[ALANSD]

we only had a small one with us, and are gonna try another next time.

[StevieB]

Alan,
I tried it on my Avion, .... that is a room AC Unit in a closet and vented out thru the side thru a vintage refrigerator vent. It would only drop it a max of 8-10 degrees. I hate to say it, but it sure is nice with a Coleman Low Profile AC Unit on the top of the 54. I did not want to do it at first, ..... I looked for all the ways to not disrupt the roof line, even considered the Atwood Truck Cab Unit and the Climate Right Unit, ..... but I gave in, and I am sure glad I did. You saw the unit on top of our 54 Safari at Atlanta Motorama, but you probably did not notice it much because I painted it aluminum.
Regards,
StevieB

[ALANSD]

Yes that is another way to go. Tried a tower type fan in there today, it was 90 and humid as heck. Got it pretty comfortable in a shorter time.
Your trailer was very nice. Summer in Georgia is just not our best season.

[AlumiDillow]

I have some experience with this in my 19ft 64 Globetrotter. When we bought it there was a big rooftop unit(it was a lot profile but still looked huge on the GT). I removed it and got one of the 10K free standing units. Since our trailer was pretty original I decided to hide the AC unit in the old furnace cabinet by removing the old furnace which we had no intention of using and fitting the AC unit in the same space and then using the furnace exhaust vent for the AC exhaust. Also added a Catalytic heater to the front of the cabinet.


Here is the main problem with these cheep AC units. They have an exhaust but no fresh air inlet. So what happens is the unit is creating a negative pressure in the small space of the trailer. This vacuum must be equalized by hot unconditioned air being pulled in. I found air coming in from my Freg vent which could be dangerous if CM Gas is being pulled down the stack and the air was very warm. So the unit would run and run but could not really make up for the hot air being pulled in by the negative pressure created by the unit.

I finally have it working acceptably well. It will never be as good as a roof top because it is not pulling hot air from the ceiling but I am happy with the tradeoff between aesthetics and functionality.

The key was to find and isolate the air flow on the unit that is for the compressor coil cooling and pulling that air from the outside. I am pulling that air from the belly pan with a pipe running through the gaucho as it should be cooler then the ambient air temp. This created a closed loop for the air being cooled by the AC and no more hot air being pulled in to replace the air the AC unit was sending outside. On the unit I have the lower coil was for the compressor so I isolated it in my custom cabinet and am pulling that air from the pan then it is exhausted out the furnace vent on the side.

Another advantage is the unit is very quite compared to the rooftop unit.

Here is a few photos of my AC unit fab install.

https://goo.gl/photos/FKrLRMRXuMcicrdT6

[ALANSD]

Nice work there. I have removed my gas furnace but the space is under the kitchen sink in ours and quite small.
For now I will use the unit in the tub as it seems to be working ok, When it is over 90 with 99% humidity I am not gonna camp much anyway. I enjoy the other 3 seasons a lot and will continue to try and use the trailer at least once a month ad we have done