12 volt roof AC

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The problem with the "portable" units that use a hose to eject the hot air from the condenser is that they also radiate heat. After an hour or so, the heat exits the case of the unit itself, then it is in a never ending cycle to cool the space and itself, which is radiatively heating said space. The best thing is to use a 5000 BTU window shaker in one of the rear door windows of the van and put a 2000W generator on a hitch mount or something similar, but then you are still only getting about 40% of a Ton of cooling where a car air conditioner typically is closer to 5 Tons.

You can't cheat the laws of physics. BTU's are BTU's and you have to "Move" the heat out of the space and regardless of whether you are using 12VDC, 120VAC or 240VAC, you still need the same amount of Watts to do the work. For example, 720 Watts is 6A at 120V, it's 3A at 240V but 60A at 12V. Think of how long your 12V battery will last at a 60A draw, and how much Solar you will need to replenish that. Not enough room on the roof.

You could probably buy a vintage air kit for your van and then you would have normal Automotive AC, just only when you drive.
 
ZoNiE said:
The problem with the "portable" units that use a hose to eject the hot air from the condenser is that they also radiate heat. After an hour or so, the heat exits the case of the unit itself, then it is in a never ending cycle to cool the space and itself, which is radiatively heating said space. The best thing is to use a 5000 BTU window shaker in one of the rear door windows of the van and put a 2000W generator on a hitch mount or something similar, but then you are still only getting about 40% of a Ton of cooling where a car air conditioner typically is closer to 5 Tons.

You can't cheat the laws of physics. BTU's are BTU's and you have to "Move" the heat out of the space and regardless of whether you are using 12VDC, 120VAC or 240VAC, you still need the same amount of Watts to do the work. For example, 720 Watts is 6A at 120V, it's 3A at 240V but 60A at 12V. Think of how long your 12V battery will last at a 60A draw, and how much Solar you will need to replenish that. Not enough room on the roof.

You could probably buy a vintage air kit for your van and then you would have normal Automotive AC, just only when you drive.

Has anyone ever tried or have experience with the Turbokool rooftop evap cooler?  I just discovered it online tonight.  It's a 12v system that draws at maximum around 4 amps.  It fits in a standard 14x14 opening, and can be also used as an exhaust fan.  I live in Las Vegas so being in the western US, will generally always have low humidity.  If I was able to get 20 degrees or so of cooling, that would be about all I need.  Seems like a really cool solution to a serious problem for someone like me who lives in an oven during the summer.

Interested in any thoughts.
 
they use a lot of water. the hotter and dryer it is the more water they use. highdesertranger
 
Those RV Evaps are tiny and only add humidity. We had one on our truck camper growing up and it sucked. Plus past 100 or so degrees, forget any cooling at all. Waste of money.
 
Swamp coolers require dry conditions, lots of air flow and lots of water. It can be less expensive to set up and run initially but you end up still needing to provide the power and water for a limited ability.
 
Joseph_Grey said:
I picked up a Harier (sp?) 8000 BTU portable unit that just fit between the seats in my cargo van. It ran great for a couple of hours, then after that it would keep the van cooler, but couldn't get it below 80 on a 92 degree day, sitting in the sun. I took it back to the store yesterday and they are sold out of the unit I had. I guess they had lots of returns. Instead they recommended an LG so I am going to give that a shot. I only really plan on using the AC when The Wife is along, and for those times we will be in camp grounds where we can plug in. The LG is a taller unit and actually has a little smaller footprint, so it is easier to get around when it is between the seats. I am building an exhaust that can blow out the drivers side window.

--joe
I was researching. There seems to be a huge difference between those portable units with a single hose vs the ones with a dual hose.

Basically, the single hose uses air inside the van to cool itself and pumps it out.
The two hose one uses air from outside and the condensation to cool down
Price also huge difference. 200 vs 800.

I would probably set up against a wall and cut a two holes to vent hot air our. Basically. There will be no hot hose inside the van.

Sent from my Life One X using Tapatalk
 
if you put a swamp cooler on the roof the heat in that area will evaporate the water quicker. I have my swamp cooler inside, even on a hot day I rarely use more that 4 liters of water. Anything on the roof will get hot, when I had vents on the roof, all they did was blow hot air in my van.

If you are going to use a swampcooler it's best to have alot of foam insulation in your van. I've been using swampcoolers in my van for 4 years in southern california, not the driest climate but it works excellent for me. Less than 3 amps of power use in the hottest weather and I park in the sun. If one small swampcooler don't work, try 2 of them or get a larger one with a giant car radiator electric fan (about 6 amps).  If you build one with 2 car radiator fans, that will definitely cool you down. 
The fantastic fans are more or less an exotic car radiator fan that is speed governed to use no more than 3 amps. Thats why they last for years, the car radiator fans will run at max rpm all the time, they might last you an year when used in a swampcooler.  But they cost 20 dollars to buy a replacement fan.

Unfortunately you have to build your own swampcooler, the ones available on the market are too expensive and I havent seen one that is actually built to use in a moving vehicle. The turbokool costs 600 dollars and uses some sort of foam pad (they call them filters in there ad), those get clog after constant use like the swampys. You want to use the celdek evaporator pad, never gets clogged and lasts 5 years. Its what I use. 

If you got power to spare get an AC, if you have limited power get a swampcooler, and if you can park in the shade all you might need is a fantastic fan. 

This shows the temp in the front of my van and also in the back where I am heavily insulated and have my swampcooler running. Where the cooler is actually blowing is alot cooler in the 80's. This is parked in the sun with all the windows/doors/vent closed. 
temp lcd.jpg
 
Even the smallest swampcooler I've used was better than my fantastic fan.
fantastic fan.jpg
 

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jonyjoe303, those are some interesting ideas you have come up with.
 

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