Portable 12V Air Conditioner --Cheap and easy!

Step 9 Operation

Pretty easy, really. Dump in enough ice to fill the cooler about 3/4 of the way, pour in about a half-gallon of water (thats two liters for the smart people) so that the bilge pump can work, and plug it in! And flip the switch if you installed one. Make sure that you open the lid slightly for return airflow. We found that flipping the handle over to prop up the lid provides plenty of airflow without letting the ice get too warm.

If everything is hooked up right, the pump should be humming away, and the fans should be blowing. The water is chilled enough to cool the air within a few seconds. You can put this in your car with the dead A/C (note: this will cool pickups and small cars. Don't bother on your Ford Excursion), you can hook it up to a wall outlet through a 12V battery charger, or you can clip it onto a small 12V gel cell.

Comments

[Blackice504]

you should get some peltia for it they work really well and there only 25aud all you need is a heatsink for them on the outside and they will freeze on the inside and you will have a fridge they also work on 12volt.

[bryan3141]

Interesting idea...but how are you going to vent the heat sinks to the outside? i'm already giving up one passenger space for the cooler....

[bryan3141]

I'm thinking to myself: "self...why not just run the tubes through the top of the cooler and put the heat exchanger and fans in their own enclosure, thus eliminating the open icewater in the jostling car." I think I may follow that advice. I'm thinking 3 holes through the top of the cooler: cold water supply to the exchanger, used water output to the cooler and condensation return to the cooler...or, if I have a clean enough heat exchanger, maybe I'll run the consdensation collector into a drinking bottle...fresh cold water on a hot day is always a nice thing.

[Billgun]

Will dry ice work?

[CameronSS]

Read Step 12.

[flatcurve]

Do you use ice cubes or big blocks of ice? If the former, consider using larger blocks. They'll give you a little bit more longevity because they'll melt slower.

[dserhal]

What about putting salt in the water? Doesn't that allow a colder freezing temp?

[mbainrot]

another suggestion is if your fans are powerful enough, you could have one fan blowing in, and one fan blowing out, it would effectively force the air through the cores twice (Once throu in, once through out)

[GrinnDaddy]

You could always try drilling a 1" hole in the lid for return airflow, and seal a hose in it that goes below the heater core. That way the outside air "sucked" inside would have to pass through the heater core, but you'd still only have a minimum amount of cool air escaping from the cooler.

[monkeyhihi]

Well, I don't know much about electronics, but couldn't you install a smaller fan (blades reversed) that would run off of the same power, and thus provide return airflow? Or not, I'm not too sure how that would actually work.

[CameronSS]

You could flip the fan over (not as pretty) or reverse the polarity (not as efficient) to get reverse. We considered it, but figured that the air would get trapped in the small space between the heater core and the fans, and never actually go through the core.

[DeadlyDad]

A plastic shroud would solve the problem of air leakage. A line of glue/epoxy/etc. dribbled through the radiator would provide a barrier between the two halves. The problem is that it would cut your airflow in half, thus making it take twice as long to cool the area. A better solution would be to

1) Attach a hose to the output.
2) Mount a screw on the inside of the top of the chest bottom, and a swiveling notched bar to the lid. You can then, by slipping one of the notches onto the screw, set the lid at any angle that you want. (Because the distance from the water is unimportant, the cooling array doesn't have to be right on top of it.)

Actually, an even better solution (in terms of noise, wattage, and geekpride - I'm not sure how the throughput would compare) would be to get rid of the fans altogether, and use a 12v ion generator ($30) like was used for this ion cooled computer.

[monkeyhihi]

Well, while I guess cracking the lid isn't the most "graceful" option, it's certainly the one that works best. Great instructable.