OT Cold water 12 volt air conditioner for the 914., Anyone tried this? Options

[Elliot Cannon]

I researched these air conditioners on the internet and found they cost about $700 to buy. I thought I might try to make one myself. How hard could it be rite? I started with a closed loop water circulation system. It is powered by a 12 volt 2 amp pump with a gallon per minute output. I got it at the local RV parts store. Bent some 3/8 inch copper tubing to fit into an old cooler we have in the garage. Connected some 3/8 rubber hose and used a heat exchanger I bought at a flea market for $5. Filled it with water and tried to bleed out as much air as possible.

[angerosa]

That is way cool! I actually had I colleague at work try something similar with his computer CPU.

The salt in the water will lower the boiling temperature and the freezing temperature of water which is why they put salt on the roads in the winter and you put salt in the water when you're making pasta. The pasta doesn't taste any different, they just believe it will come out better if the water that's cooking it isn't 100 degrees C. Water will come to a boil faster too.

It also changes the specific heat of the water which means it will absorb heat more redily and quickly but you will melt your ice faster so you should get a lot of cooling but your system will "burn out" quickly.

The best thing for a long trip is to have the cooler in a freezer so it's already cold and fill it to the top with pure ice cubes. If it's already cold you won't waste cooling power bringing the inside of your cooler down to temperature. The ice will melt and the water will be at 0 C instead of putting an ice/water mixture in and having the water rob you of cooling power as the ice brings it down to 0.

Some problems you may have is that when the ice melts your cooling coils may not be fully submerged. You'll have to test it out. If you're going on a short drive I would put the water and ice mixture in there just like you planned.

Your heat exchanger is going to create a lot of water from condensation so you may have a puddle in the trunk or where ever your going to put it.

[Elliot Cannon]

That is way cool! I actually had I colleague at work try something similar with his computer CPU.

The salt in the water will lower the boiling temperature and the freezing temperature of water which is why they put salt on the roads in the winter and you put salt in the water when you're making pasta. The pasta doesn't taste any different, they just believe it will come out better if the water that's cooking it isn't 100 degrees C. Water will come to a boil faster too.

It also changes the specific heat of the water which means it will absorb heat more redily and quickly but you will melt your ice faster so you should get a lot of cooling but your system will "burn out" quickly.

The best thing for a long trip is to have the cooler in a freezer so it's already cold and fill it to the top with pure ice cubes. If it's already cold you won't waste cooling power bringing the inside of your cooler down to temperature. The ice will melt and the water will be at 0 C instead of putting an ice/water mixture in and having the water rob you of cooling power as the ice brings it down to 0.

Some problems you may have is that when the ice melts your cooling coils may not be fully submerged. You'll have to test it out. If you're going on a short drive I would put the water and ice mixture in there just like you planned.

Your heat exchanger is going to create a lot of water from condensation so you may have a puddle in the trunk or where ever your going to put it.

My plan was to use water with ice in it. That way the copper coils will always be covered. I will use a drain hole so any condensation from the heat exchanger will drain back into the cooler. It will be interesting to see how long the ice will last. I'm thinking about 4 hours but that's just a guess. Mini-marts don't seem to be that far apart even on the interstate. Seems like every service ahhhh I mean gas station is also a mini-mart as well. Obtaining ice shouldn't be a problem.
Cheers, Elliot