AC for Enclosed Trailer?

A while back I asked about cool suits because I baked at Buttonwillow. After some thought I realized it wasn't the in car portion of the day that was melting me but the hanging around in the paddock part.

My Camper Van really isn't big enough to hang out in, the coach AC is to small to cool it off anytime it's over 80 degrees and I can't run the van AC all day. The van didn't come with a generator and my 2000 watt portable won't run a bigger AC; even if I did upgrade we still have the issue of the van be small.

My thought is maybe install some kind of cooling on the trailer; I could install a large generator on the front of the trailer to power a 15000 BTU or similar unit.

Anyone ever try this?

I have AC in mine, the install was fairly straightforward.  Ideally you want the generator inside the trailer in an enclosed box with an exterior door on a set of sliding rails so you can pull it out when you want to use it, but put it away out of sight and rain when not using it.  Put in a breaker box and run some conduit up to the roof, cut a square hole for the AC, set it on top, and bolt the control unit on the bottom.  The hardest part is getting the AC unit up onto the roof of the trailer, they're pretty heavy.

You'll want a PVC curtain for the side door (like on a meat locker).  Some people put big ones at the rear door too, but I usually just close it.

I have a 13,500 unit, but my trailer isn't insulated.  It can't cool the trailer down if it's already 100 degrees in there, so I need to start it in the morning when it's cooler and keep it running during the day.  It'll usually maintain 15-20 degrees below ambient.

I've thought a mini split with the exterior unit mounted on the tongue would work well. I see them in the wild, but I wonder if the better play is the camper style roof unit. 

I put an AC unit into my trailer. It was easy.  Georgia summer laughed at it and said "nice try dude."  The heat coming through the ceiling and walls completely overpowered it. IMO if you're not going to insulate and seal all of your walls, it's pretty much a pointless exercise. 

Even with insulation you're going to struggle to get much more than 20* below ambient unless the system is wildly oversized. Not saying not to do it, just manage your expectations and/or plan accordingly. We learned this the hard way at solo nats last year with the modern-ish RV we had at the time. The temperature gradient away from the unit was significant, like "move over a seat on the couch and it's noticeably warmer".

In reply to ShinnyGroove (Forum Supporter) :

Yeah I am dealing with a similar deal here in the desert.

I have a 14000 BTU portable at that I could vent out the roof hatch.My trailer is only 8x16 so it might do the job.

The trailer really needs extra roof spars to support the weight of the ac. Those aren't that easy to add if they weren't factory installed.

I have a couple of buddies that added cheapo minisplits to their trailers,  and they seem to work great. Probably not designed to survive the vibration they'll see on a trailer, but have been runing fit 2-3 years now. 

Even 20 below ambient is huge -- 85 in the trailer when it's 105 outside feels heavenly.  I will admit that I position my chair directly under the vent, though. :)

This outfit makes 12/24/48 systems https://www.cruisencomfortusa.com something might work for you. There's also the DeltaWave and Delta Flow that will bring the batteries for the system.

Maybe you could throw in another curtain inside the trailer to keep the air in a much smaller volume? having a 10x10 box to retreat to would be amazing.

If you are ever considering purchasing a new enclosed trailer, its worth getting them built with the A/C prep package.  Saves a ton of horsing around installing the unit.  And yes, unless you want to comically oversize the unit or can be guaranteed shade, you are gonna want insulation.

Another option is a swamp cooler, but they are bulky to transport and need a decent bit of water.  

As far as other cooling, what color is the roof?   When i got my trailer it was bare galvanized. I painted it white and saw a HUGE drop in temperature difference to outside. Its still a bit warmer, but not heat-stroke. 

In reply to Tom1200 :

This is worth trying if you already have it. Maybe you can borrow a buddy's generator?

I have an 8000 btu portable that i used in my 8.5 x 24 and i added 1 inch styrofoam to the ceiling. It worked ok in the summer until around 3-4pm or so, then couldnt keep up in the high humidity south east. 

You might have better luck with more cooling, and a smaller space.

Rons said:

This outfit makes 12/24/48 systems https://www.cruisencomfortusa.com something might work for you. There's also the DeltaWave and Delta Flow that will bring the batteries for the system.

Yes, but have you seen the amp draw on the 18kbtu unit?  95A at 12v, and even if you do the 48v version, you'll still need the same number of batteries... which will be a lot, plus some way of recharging 1,440,000 Wh.  That's about the equivalent of two forklift batteries, which weigh about 2000 lbs each and cost as much as a small country.

In reply to sevenracer :

With all the replies here I've started to give a lot of thought to using the portable AC and partitioning off the trailer as I do this with the van.

I have thick curtains behind the driver and passenger seats so that the van AC doesn't have to cool off the whole van. This works great.

The garages at Buttonwillow have power so I could run an extension cord to power it.

The garages at Buttonwillow have 125v 30amp RV plugs you could plug your trailer AC into.  Lots quieter than a generator.  We also let our neighbors run extension cords to the normal 120v outlets.

We rented a toy hauler to sleep in at Buttonwillow a few weeks ago.  It was cooler than outside (100F), but not cold.  It had a single roof AC.  It was better at night.

Tom1200 said:

With all the replies here I've started to give a lot of thought to using the portable AC and partitioning off the trailer as I do this with the van.

I have thick curtains behind the driver and passenger seats so that the van AC doesn't have to cool off the whole van. This works great.

The garages at Buttonwillow have power so I could run an extension cord to power it.

Yeah, Buttonwillow or Thunderhill you can get power in the paddock fairly easily.  Sonoma or Laguna is where you need the generator.

What about a RV AC?  The unit in our R Pod made things cold pretty quickly.  The trailer did have fair to middling insulation.

I think an RV AC is the answer.  It won't be stellar, but it will be adequate.  The cost, on the other hand, can be pricey because it says the word "RV" on it.  You're looking at $700-1000 for 15kbtu.

I think you could get past the weight issue by mounting it close to the front and adding some angled supports under that area.

I think the cheap button is to cut a hole in the front and install a standard window unit.  Then you're looking closer to $400, and you can probably find one on FBM for $100... maybe even free.  Add a fan.  Most window units are great at cooling, but not as good at blowing.

Curtis73 (Forum Supporter) said:

I think the cheap button is to cut a hole in the front and install a standard window unit.  Then you're looking closer to $400, and you can probably find one on FBM for $100... maybe even free.  Add a fan.  Most window units are great at cooling, but not as good at blowing.

 

This is what I did. But I had a 6x12. Black trailer in south Texas in the summer.  I had a 5k window unit that kept it around 78 in 110 degree heat. Upgraded to an 8k and it would get down to 70. Three things that helped were pink foam core panels between the outside and inside walls, thicker foam core in the ceiling with the aluminum coating on one side and the biggest help was a gallon of white cool roof coating from the local home improvement store. 
 

-Rob

So, how much is a reefer unit off the front of a straight truck worth used? Lots of cooling and heating as a bonus. If you're really creative you could pull power off of it too and leave the generator at home.

In reply to adam525i :

They're stoopid expensive.  I found one on LKQ just now (rabbit hole for my curiosity) with 5500 hours on it and they listed it for $13,500.  They're also serious overkill, which isn't always a benefit with A/C.  That particular unit was a 2-stage.  First stage was 30,000btu, second stage was 60,000.  The engine was 34hp, and it took 13 lbs of refrigerant.  I'm sure they make smaller ones, but how small I don't know.  Maybe one from a refrigerated Transit or small box van?

In reply to Curtis73 (Forum Supporter) :

You could probably run large ducts to all of your friends trailers around you!

A friend had a Carrier brand unit off a short school bus. Problem is it used the engine compressor. Up side is he scrapped the bus for what he paid by selling off the A/c parts to the county school bus shop.

Simple unit, maybe an A/c expert could come up with a way to use the 110 comp out of a home fridge or freezer?

In reply to AhBNormal :

Home fridge or freezer unit would be about 500 btu.  You would need about 30 fridge compressors to do the job in the trailer.