Question on single hose vented AC units

[DrNosty]

Hi All,

New to the forum. I'm in the process of converting a 6X12 cargo trailer into a bed away from home. I built a teardrop ten years ago and, now that we're retired, we want just a little more space. Specifically, a space we can stand up in.

My question is this: I've been looking at a single hose B&D 10K BTU AC/heat/dehumidifier combination to heat and cool the unit. We live in TN so it gets pretty warm in the summer and, with kids in Florida and Mississippi, we're going to be spending time in both places.

I've seen a whole lot of varied comments on these units on these forums and I was wondering if someone with some experience with the single hose units in their TT could enlighten me somewhat. Someone who uses one, or who has used one, and what your thoughts are on them.

Any constructive input would be greatly appreciated. Thank you.

Dr Nosty

[martymcfly]

I used one last summer in my 7x12. I vented it out of a window using a piece of rigid insulation. It was 110 F. outside in Hells Canyon. It ran constantly and did O.K. I guess. I would thought that it would have done better than it did. It did better with the roof vent cracked open a little bit, otherwise it seemed like it was a vacuum in the trailer.

[Gulfcoast]

If a single hose is good.... then a double hose should be twice as good. Why not spend a little more and get the best you can buy. I use a 5000 btu window unit and dont have to worry about the unit using my cool indoor air to cool the condenser.

[DrNosty]

Thank you for the replies. I'll look into the double hose unit. Until yesterday I didn't even realize there was a double hose option.

[Tas]

Do a search here and you’ll find more info than you’ll want. It’s been debated almost as much as which oil to use in your motorcycle. I have a dual hose 11600btu in my 6x12 and it works well but honestly haven’t used it much in +95°F weather.

[Gonefishin]

I bought a little single-hose two years ago for my marginally-insulated 6X12, and a Honda 2200 to run it. On a 90 degree day in the dry Rockies, parked in the sun, it cools my trailer down to the high 70's/low 80's. If I aim it at the bed, it makes a nice cool breeze in which to take an afternoon nap. It is mostly a "personal cooler" that takes the edge off. Two hose would definitely be more efficient. And then more traditional A/C or mini-split would be a huge step up. But for what I need, its working and I'll keep using it. For the areas you are talking about, I would go with higher efficiency for sure, with more heat and more humidity to deal with.

[onehoser]

i started out with a single hose portable a/c which worked okay for my needs but ended up installing a window shaker unit vented through the floor, much better and it doesn’t take up floor space as it’s under the bed

[Shadow Catcher]

There are a number of those who have done variations on this. A hacked 5000 btu window unit. During our 90F 90% summer days there is a substantial puddle of condensate, with a 50% duty cycle.

[Rolando1994]

Just started a hasty attempt to convert my black 6x12 v-nose cargo trailer into a sudo-camper for an upcoming trip. I bought a 5,300BTU (DOE/SACC) single-hose unit and installed a 6in hatch in the very front floor for the exhaust. Not impressed at all and am feeling deflated. High today is 80F and after 4.5hr of run time starting at noon the thermometer I set up is showing 89F in the trailer, about 10 degrees cooler outside. Sure maybe it's worst case; full sun, started at noon, black trailer, no "insulation"... but kinda bummed. Dunno what I need to do... get a bigger BTU unit, paint trailer white, abandon probable to a window unit, or what.

Being an engineer by profession I run into analysis paralysis a lot. Researched portable A/C units out the wazoo and got all worried thinking I'm gonna need some massive unit bordering on a mini split. Decided to move forward from the paralysis, bought the above unit thinking it's 78 square feet...

[Larry Carlton]

I have an 8k one hose portable AC unit in my 6x12 CT conversion. I used Coroplast to create a box around the unit's intake vent area and ran a 2nd 3" hose from the box and vented both hoses out the floor. I purchased round marine vent enclosures with screw on lids to close off the vents when not in use. I went from an underperforming AC unit to one which now cycles the compressor and keeps the CT in the lower 70s. I live in PA and we get into the 90s with 70-80 percent humidity. One other change I have planned is to insulate the exhaust hose. I have the AC unit installed in the front of my trailer under my kitchen counter. The heat builds up under there and I believe I can further increase efficiency by insulating the pipe. The portable single hose units work great with the addition of the 2nd hose.

[Gulfcoast]

I can't find anything that will work better than a mini split for a cargo trailer. Low power draw, easy to install and will cool down a well insulated trailer to 70 with ease.

[Larry Carlton]

I can't find anything that will work better than a mini split for a cargo trailer. Low power draw, easy to install and will cool down a well insulated trailer to 70 with ease.

I agree, the mini splits are very good. But for my needs and the space allocated for an AC unit, the portable works great. I paid $280 for the unit on clearance and it has an inverter rotary compressor that sips electricity. I can run my 8k unit off of my Honda 2000 inverter genny and keep it on the economy mode. I tried posting a picture but I guess my advanced age prohibits it..ha..ha.

[Bruce R Leech]

Why not just use the RV rooftop air conditioner unit

[Grummy]

Not impressed at all and am feeling deflated...... bought the above unit thinking it's 78 square feet...

We've seen plenty of failures when it comes to these single hose units when not used inside a traditional home. The double hose units are "better", only in that they have what the single hose is missing, that being the necessary circulation of air flow to cool the condenser.

The whole problem with the single hose is that you can not expect it to work if you try to suck the trailer flat. The exact amount of air flow in CFM that goes out the single hose has to come into the trailer somewhere. Frankly, a regular old house has a whole lot more of "leakage" than these trailers, and easily (usually) allows enough air thru the machine.

If you were to put a thermometer in front of the cool air coming out when all your trailer doors and windows are closed, then check it when the doors and windows are open, after it has time to settle, you should be seeing a big difference in the temp. Problem is, you can't cool a trailer if your sucking in as much outside hot air as is going out thru the hose.

And a lot of people also do not think about "free air" CFM... where, if say, you add another 10 feet to the hose, there is no way the existing fan as designed can pull the same amount of air thru that additional length of hose as what it was designed for. In this case, it can be accomplished, but only by adding yet another fan to boost that air flow.

The issue is the similar with a window shaker. There they pull air in from the sides (where it normally sticks outside the window), and blow the hot air out the back. If you build one into a cabinet, you have to provide at minimum the same amount of free flowing air as if it was hanging out a window for it to work as designed.

Not having insulation is probably not going to work efficiently with any air conditioner as all that aluminum both absorbs the heat and dissipates the cold all too quickly. DONT BUY another single hose.... But you could try to isolate the intake depending on how it is built, so only outside air gets sucked in and back out thru the unit, not affecting inside air that is recirculating the cool stuff.