A/C for my Jeep

playhard

Observer
I would like to start using my jeep for longer trip in the summer. I do not have A/C. The hot Oklahoma summers plus the wind that my wife and 4 year old don’t like and having to scream at each other just be heard limits our jeep use. Admittedly I know nothing about A/C units. So my question is why couldn’t I set a window A/C unit behind the back seat of my jeep yj along with a 1000 watt invert and have A/C for around $250? Is there any type of exhaust from the A/C unit?
 

PhulesAU

Explorer
This can work. Be sure your inverter is enough capacity to carry a/c startup load and Jeep alternator can carry the extra running load. Be aware a window a/c needs its backside extended thru to the outside just like they do if installed in a building. Thats where the removed heat escapes to.
Perhaps use a portable a/c, venting its exhaust hose outside is much less work.

If you go with a windowmount. Be sure to occasionally park at WalMart. Folks like to take pictures of this sort of thing.
Bonus points if you bumper mount a portable generator.
Btw.
Dont be embarassed. You will be in hiclass company. Its reported Mayor of New York does this similar with his Chev Suburbans.
LIKE!!!!!
 

Eaglefreek

Eagleless
As mentioned, a lot of heat comes out of the back of the window a/c unit, so you have to have it separated from the interior and hanging out the back or side. Did your Jeep not come with A/C or has it been removed in the past? I'd look for used parts out of another jeep that someone removed. The only item that would need to be put in new would be the receiver/drier.
 

playhard

Observer
This can work. Be sure your inverter is enough capacity to carry a/c startup load and Jeep alternator can carry the extra running load. Be aware a window a/c needs its backside extended thru to the outside just like they do if installed in a building. Thats where the removed heat escapes to.
Perhaps use a portable a/c, venting its exhaust hose outside is much less work.

If you go with a windowmount. Be sure to occasionally park at WalMart. Folks like to take pictures of this sort of thing.
Bonus points if you bumper mount a portable generator.
Btw.
Dont be embarassed. You will be in hiclass company. Its reported Mayor of New York does this similar with his Chev Suburbans.
That is hilarious!!! My wife will not go to WalMart so there is no way I could get her to ride in a jeep that belongs there. I forgot about the fan blowing on the coil in the back to get rid on the heat. The portable units are probably the way to go but an extra $100. Vintage Air would be around $1500 and a lot of work to put it on. So $300 to $350 doesn't sound that bad.

The A/C unit was not on the jeep when I bought it. A York compressor is now in its place for on-board air. I really don't want to loss that setup. The couple jeeps I have had in the past(all pre-TJ) would freeze you knees off but that rest of you would still be warm.

Thanks for the help!
 

chasespeed

Explorer
Okay. Keep in mind, you need to factor in, in-rush current in the inverter. At LEAST 2000watts.
Second, the type of inverter can be an issue... depending on the unit.

Second..... if it's a YJ, find a one with AC, and take the parts. More reliable, clean.

And quieter. A window shaker is gonna be noisy in a close cabin.

Just my opinion.

Chase
 

jeep-N-montero

Expedition Leader
Okay. Keep in mind, you need to factor in, in-rush current in the inverter. At LEAST 2000watts.
Second, the type of inverter can be an issue... depending on the unit.

Second..... if it's a YJ, find a one with AC, and take the parts. More reliable, clean.

And quieter. A window shaker is gonna be noisy in a close cabin.

Just my opinion.

Chase
A buddy of mine just did a junkyard A/C swap out of another YJ and it works awesome, best way to do it for sure.
 

playhard

Observer
Thanks for the information but I do not want to give up my on-board air which I would have to do to make room for an A/C compressor. I'm also running a chevy 350 so I would need custom line made up. I'm trying really hard to not put any more "custom" stuff on my jeep. I will probably look at the portable A/C units instead of the window units when I get more money saved up. Just bought new tires and a winch last weekend. :)
 

XJINTX

Explorer
Just me but the compressor would go and AC installed. I'm down in TX and noway would I highway drive anywhere in the summer without AC. As already mentioned a JY will have all parts necessary and the rice should be less than "MacGuyverising" it. The onboard air can come from many other sources. I personally use CO2
 

1stDeuce

Explorer
Engine driven A/C is really you're only good option, unless you only want to use it when you can plug in an extension cord. :)

The problem with window A/C from your battery/alt/inverter: A 5000 BTU A/C unit is ~850 watts, which would be is 7 amps at 120v. That would require 60A at 14v, but the inverter is not 100% , so it would need more than 72A to run it through an inverter. You'll definitely want a pure sine inverter, as motors don't like modified sine, and will use even more current to operate.

72A is likely more than your alternator can put out at idle. If you have an electric fan, they draw 20-30A, so add that and you have a 90A load on the alternator... Even if you have a modern 120A alternator, that's a LOT of static load, and your alternator and batteries will not like it long term. Alternators only put out rated amperage when they're spinning pretty fast... At idle you'll probably only get 30% of rated output.

On top of that, starting current for the A/C unit is easily double or triple what the running current is, and it'll take a big inverter to start it. And big inverters need bigger batteries, since you can't just pull huge amps out of a small battery without tripping the inverter's low voltage alarm. I'd recommend a 2000W or bigger inverter, and two Group 27 batteries for the best performance. That would also cover times when you're idling and the alternator can't keep up too.

I'm not saying it can't be done, but it probably isn't the best plan long term. Especially since you'd have to hang the back of the A/C unit outside of the interior of the Jeep. I don't think there are RV style roof mount units as small as 5000 BTU, but if so, that would be ideal if you have a hard top. Or if you can find a 12v unit out of an ambulance or something like that, even better, since you could skip the inefficient inverter. I suppose you could go total hillbilly and knock out a rear window and plywood over it, with a window mounted A/C unit hanging out...

Depending on how your current A/C pump is mounted, you may be able to mount a second pump by just getting brackets from a different vehicle. It would be worth a little looking... YJ A/C parts are probably going to be difficult to find in a junkyard, but you don't know till you look... Retrofit kits are available, and they might even be able to supply a pump bracket that will work with your current setup.

FWIW, I had the A/C pump in my TJ converted to air compressor, but I fried it this spring by letting it run too long at high pressure. I'm planning to replace it, because I do like it, and it's all set up, but I have a Viair 400c pump mounted in my truck, and it's pretty fast too, particularly if I'm just airing up to 30psi or so. If I ever decide I want A/C, I'll not hesitate to go to a 12v compressor.

Sorry about the book... And Good Luck!
 
Last edited:

M35A2

Tinkerer
Thanks for the information but I do not want to give up my on-board air which I would have to do to make room for an A/C compressor. I'm also running a chevy 350 so I would need custom line made up. I'm trying really hard to not put any more "custom" stuff on my jeep. I will probably look at the portable A/C units instead of the window units when I get more money saved up. Just bought new tires and a winch last weekend. :)
Get creative and build a mount for the second compressor. Or buy an electric compressor for OBA. So many technically correct options and here you are talking yourself into a total embarrassment of a hack. Those guys up there responded tongue in cheek - you missed that. It is a total mistake and hack to use a window unit. One of many reasons that is not a good idea is that they are not designed to handle vibration. But so what? Go for it, pardner.

If you persist, post a build thread and update with real-world performance as we can use the laugh.
 
Top