AC ducting question

[kd5edj63]

I have a 5000 btu room AC unit. I have thought of a simple way to duct in only the cool air without "extracting" the humid air. In other words only pumping in the cool air and let the unit evaporate the rest of the world. How effective will this work. I'm not a wimp by any means, and I know its not gonna be 100%, but will it work "fairly well". I plan to use a 6" dia. semi rigid aluminum hose, as short as possible (about 3 feet)

[aggie79]

Bob Henry has done this on his little red barn TTT.

The challenge will be how to control the temperature if you don't duct the return air. The thermostat in the unit will be sensing the outdoor air temperature.

[Jiminsav]

I do believe you have to extract the humid air from inside or you will have condensation dripping from the ceiling

[kd5edj63]

Well, I can do without the condensation, but I dont mind going outside to shut the unit off, or, wire up some sort of on-off switch from the inside. Im not looking for household comfort, but want to beat the texas heat a little. I will probably camp 2-3 times a year with the AC unit. I mostly get water only sites

[mikerueve]

I'll let you know how it works. we're about to try to tackle Route 66......

[flboy]

I'd think that would work and since it is going to put a positive pressure on the trailer, it should stay relatively dry. I'd be more concerned with the efficiency of the AC pulling in hot air to cool all the time. I the correct environment, the return air is getting cooler also. King of like running your car ac on Max mode verses outside vent. On real hot days.. it may have a hard time.. but the trailer volume is small.. so it make work just fine. I'd say try it and see.

Let us know how it works.

[aggie79]

You can get a thermostat that runs on high voltage that will turn the power to your unit on and off. I bought one for my tongue mounted PetCool but never did install it.

As far as condensation you should have any from the cooling air - just from breathing. Just leave a window or vent cracked open.

[kd5edj63]

OK, I did a mock up using left over insulation foam and duct tape. Worked very well. So I spent a few hours making something permanent and easy to set up with minimal intrusion to the trailer structure. Plug with circut breaker switch is neatly mounted inside for on-off switch. I can also regulate by moving the window glass. I can tell you, putting the pipe up close too the window is too close. I'll have to keep it a few inches away. I will experiment with a dog house type set up over the vent fan for use in the rain. I'm interested in the "Pet cool". Sounds like a smaller AC unit or something. This unit is definately overkill

[working on it]

I can also regulate by moving the window glass. I can tell you, putting the pipe up close too the window is too close. I'll have to keep it a few inches away. I will experiment with a dog house type set up over the vent fan for use in the rain.

If I'm reading this right, you're intending to "aim" the end of the pipe into the opened slider, but still allowing unfilled, un-screened, space all around the pipe? In my experience, it seems that you're asking for unwanted insect incursions (and pollen, and dust free entry also). Part of the beauty of air conditioning is that it filters out those items. By leaving even the smallest crack in the armor (the opened window), the bad stuff gains entry. When I use my A/C, I still use slightly opened, screened vents, but I have computer fans blowing outward thru them, hopefully keeping pollen and dust out as well. Other than that, with a rainshield over your unit, it looks like it'll work. Still, Tom's suggested thermostat would be a good addition, for temp control while sleeping (especially).

[aggie79]

This is an example of a line voltage thermostat:

http://www.amazon.com/Lux-Heating-Cooling-Programmable-Thermostat/dp/B000E7NYY8/ref=sr_1_5?ie=UTF8&qid=1403530962&sr=8-5&keywords=line+voltage+thermostat

[bobhenry]

I have been taking only the cold cold air off of my 6000 btu fridgidaire unit with no difficulty for four camping seasons. By not recycling the inside air to the unit and having it take ambient air into the cool air intake there has never been an incident of freeze up of the unit. I have all the cold air I need and if it get too cold either add a blanket of open the opposite window and allow a bit of warmer outside air to balance the temp. I never entertained interior off and on or worried about thermostatic control. Into the cooler early morning hours if it get too cold I simply todder out and shut the unit off. If I am in the barn trailer I tuck the unit under the trailer on a wooden drain rack. This allows the unit to work in the shade and rain protection of the trailer and simply pump the cold air in thru an open window fitted with a duct. No condensation, no bugs, and no freeze up. ,

Scroll down a bit for pics....

http://tnttt.com/viewtopic.php?f=2&t=56563&p=1024811&hilit=66430#p1024811

[Shadow Catcher]

I have met folks that have done the one hose in as BH has. They were under very serious humidity a bit swampy. this is the write up on the AC I did. viewtopic.php?f=30&t=44561



You can use the thermostat from your AC

[bobhenry]

I have met folks that have done the one hose in as BH has. They were under very serious humidity a bit swampy. this is the write up on the AC I did. viewtopic.php?f=30&t=44561



You can use the thermostat from your AC

but mine's prettier

[kd5edj63]

Everything should be fine. The windows have screens. This set up is a 5 star hotel compared to an M1A1 tank in Iraq I can handle a little dust and pollin

[mikerueve]

I just wanted to report back on my experiences with my Air conditioning setup. Hopefully, this can assist others with the same challenges.

We set out for our Route 66 trip on June 28th. We were travelling from Birmingham Al to Chicago to begin the cross-country trip. As I posted earlier, I had figured a way to install my cold air ducting through the
roof vent. We found that in most cases, we didn't even need the AC. By the time we would pull into a camp ground for the evening, the weather had cooled enough that the Fantastic vent could move enough air
to keep us comfortable. Keep in mind that we are from the deep south, and anything 80 degrees or below is plenty comfortable for us. Especially if the humidity is low.

When I did elect to use the Air Conditioner, it worked well enough. I would set it up on the outside, run my cold air tube to the roof vent and keep one, or both, of the windows cracked slightly. It would cool the camper rather quickly and we usually ended up turning it off and using the vent's features before morning. This is all with the entire unit sitting outside pulling in ambient air. As I read in the paperwork that came with the AC, it will cool ambient air up to 20 degrees.

Well, then came the desert and an afternoon temperature of 114 degrees! This is where we learned about the importance of return air in the functioning of an AC. It did cool the air by 20 degrees but when it's 114 that doesn't help a lot. I also think that I was leaking a lot of cool air out the top of the vent. To make a long story short, that was the only uncomfortable evening we experienced. It did eventually cool off enough to be comfortable, but for a few hours we were not happy campers. If we are to camp in those conditions again, I'll have to re-think the installation. Fortunately, we don't, and won't be camping in those kind of temperatures very often.

On our way back, we stopped in Amarillo one evening and used the Roof setup. It was about 87 degrees when we went to bed and it cooled the tear fine. The next night, North Little Rock and about 90 degrees with high humidity. Again, we were very comfortable. These are usually the temperatures that we will be experiencing on our Summer camping trips around here.

When I got home, I decided that I'd work on a way to route the cold air tube through one of my windows, This makes it easier to set up the unit. I don't have to climb onto my fenders, and if I want to disconnect it in the middle of the night it's much simpler. I'll post a picture of this later. This setup also allows us to use the fan on the roof vent with the cold air. We tried this weekend and it is much superior to the other setup. It was 90+ degrees at 9:00 pm (85% humidity also) but we were very cool and comfortable all night. We actually ran it the entire evening. This will be my permanent setup from now on.

One other thing that I wanted to comment on is the fear that I had concerning condensation on the inside of the cabin. I had read that I could expect to have some dampness due to the fact that we are only ducting in cold air and not utilizing the return air to de-humidify the cabin air. Maybe it is the fact that we are always venting the cabin air to some degree, but we are never wet inside. There has been no condensation on the inside of the cabin. I've been pleasantly surprised by this. There is condensation on the outside. The cold air tube will be wet in the morning and the door with the window that I run it through is damp with condensation, but high and dry on the inside.

All in all, I am happy with this setup and we are able to comfortably camp in the Deep South in the dog days of summer. Below is a picture of our camp site this weekend with my revised AC steup.