Air Conditioning: How I installed it after the build

[SteveH]

When I built my teardrop I didn't think there was a need for air conditioning because almost all of my camping would be done at RC helicopter events where there would not be AC power. However, like a lot of things, that has changed and I wanted air conditioning and the design of my trailer did not lend itself to installing it inside, so I installed it using a duct system with the air conditioner outside.

There was a previous thread where this was mentioned and additional pictures were requested, so here goes.

This is the unit on the floor outside of the trailer.



The duct goes into the trailer thru the floor.


The duct in the floor is made from 4" PVC pipe.


This is the duct with a plug made from a plastic Dibs ice cream container.


Here is the air conditioner unit with the PVC duct attached. I learned if you heat PVC pipe in the oven at 250 degrees for 15 minutes, you can fashion it into what ever shape you want.


Since there was not room in front of my stove cabinet for a 4" pipe or the 90 degree elbow necessary to turn the air into the trailer, I built this wood plenum.


This is the air conditioner outlet inside the trailer at the foot of the bed.

[Boodro]

Nice Steve, like they say simplicity is everything!

[IraRat]

Well, you got it to work in a nice clean way!

And although this info isn't for me, what's the deal with inclement weather?

The control side of the AC can't handle heavy rain, but it's probably just a matter of covering it SOMEHOW. Just curious if you've already rigged something.

By the way:

As someone with a direct front-mounted unit, I can already see a huge advantage to remote-connecting the unit, venting it in. That things blows COLD on you when it's blowing directly from the unit, while all we really want to do is cool the cabin.

[cracker39]

Nice setup. What make is the AC unit? I'm putting one inside my TTT and I like the way that one vents air upward, not straight out. I saw a Goldstar at HD that vented slightly upward, but not as much as yours does. So far, it may be that one, or a Fedders with remote control.

BTW, I saw pictures of one install where the owner removed the control panel and added wiring to allow the controls to be inside while the AC was outside. No getting up and going outside to adjust or turn it off.

[davel]

Pretty cool Can't wait till next weekend to check it out.
AC does make the night's sleep a lot more comfortable.

[SteveH]

Just an update on this...we went camping last weekend and the AC worked pretty good. Just one problem, as I expected the thermostat does not sence the interior temperature as it's not getting return air. So, I either need to learn how to set the thermostat better or remote the thermostat, because both nights I had to turn it down on the way to the can. We were freezing, but it was unusually cool at Goose Island State park.

[cracker39]

One of the other builders "remoted" his controls bu removing them from the front of the A/C and extending the wiring so that the controls were inside the trailer. I think he made it so that the wires can be built in to be connected to the A/C whe in use and disconnected to store it for travel. I don't remember who did it, but there were pics of it. Anyone remember who it was?

[madjack]

...Kai (Mexican Tear) uses a regular household t stat and a relay to control the source voltage to his pet cool
madjack

[Arne]

Why not just put a return on it like you have the cool air feed set up.. not much more plumbing.

[cracker39]

That's not a bad idea. Just make a box for it to slide into with a divider to separate the cool air outlet and the return air. Then put one or two collars in each section. One to pipe air in and the other to return it back to the unit. Set the T-stat and voila...problem solved!

[samstoybox]

Nice setup. I'm considering it for my tear. Some folks who ran the controls inside their tear are members of the Five-Wide club (out of California?). I snapped a bunch of pictures at Minden of their window units which are all mounted in open bottom tongue boxes. They ran the controls through the dryer vent they used for cold air. Here is the first photo, use the "Next" link on the page to see others. There are about six pictures that pertain.

http://www.samstoybox.com/teardrop/itg2005/itg275a.html

[SteveH]

Why not just put a return on it like you have the cool air feed set up.. not much more plumbing.

Arne,

Of course, that would be the ideal way to do it, but I don't have room for any more ducting without cuting a big hole in the wall...not gonna do that. I'm going to a funfly this weekend in Austin so I might get another chance to get the thermostat adjusted correctly. If not, I'll have to figure out a way to remote it inside the trailer.

[cracker39]

Not having ever set up an outside A/C unit directing cool air inside, this is how the problem appears to me.

I see the problem is that when the ambient temperature going into the A/C is from outside and the unit's thermocouple reacts to it. The temp of the air coming into the A/C from outside won't change as the inside gets cooler, therefore it won't shut off when the inside cools down enough. The unit will will always be sensing the ambient temp of the outside air and as long as the t-stat setting is lower than the outside air you will have cold air constantly being produced for the inside.

If you did get the t-stat adjusted so that it was borderline (just about matching the outside temp) and the coolling was about right, as soon as the outside air temp drops a couple of degrees, it will be below the t-stat setting and the unit will stop producing cold air inside. I still think that the best way to get an A/C to work efficiently and accurately is to have the air flow in and out of the cabin, circulating through the A/C, so the thermocouple can work properly to keep the inside temp constant. Remember, the unit reacts to temperature on the thermocouple that is outside. Having just the controls inside would only allow you to be able to keep re-adjusting it all night long to regulate the temp and you wouldn't get any sleep.

But, if you have it done already and can't make another duct for return air, I wonder if maybe you could put the thermocouple inside. Can that be done.? Any A/C gurus out there?

I could be wrong, but it makes sense to me (JMHO).

[Roly Nelson]

I also added an AC unit after I built my tear, and slid it into the tongue box. I have a cold air inlet lined up with the cool vent on the unit, and then a matching return air opening through the front tear wall to get the inside air back into the AC unit. It really works great, will shut down if it gets too cool, and will freeze ice on the windows if left on high for any length of time. (well at least it feels that way anyway). Sometimes the first try works for a change. Good luck on your AC attempt, but I also think that routing the return air back to the unit will solve most of your problems.

Roly, looking forward to Rivernook, here in So Calif.

[Dooner]

Hey Cracker and anyone else that wants to listen,
About putting the control and as you call it, the thermocouple, in the cabin, in my 14 years working in the A/C industry, I have found that they aren't really that sensitive. They work better with air flowing across it. If you had a return air duct and it was in the duct, I would say it would be great, but just having it since the temp of the cabin is a fifty/fifty chance that you would be happy with it. It would probably get too hot before it would cut on and too cold before it would cut off.
They do make high voltage t-stats the are made to sense temperature better. Just a matter of wiring it up to a plug near where you will set the a/c on the ground. But it's back to the money issue. Is it worth it.
Well, that's my opinion. Take it or leave it. Just want to be helpful.