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...And ice water is 32 degrees.

I am reviving this thread for good reason:  I just finished building my own homebrew air conditioner!

If you're impatient and want pics NOW, here they are:  21 Pics

So how well does it work?  Well first off, it's more of a dehumidifier than an air conditioner.  Check out the condensation that forms on the tubing!  So much water was dripping off, that I had to put a towel under the fan.  Don't worry, none of the water ever touches the fans.  It gets thrown forward a few inches.    As far as cooling power goes, I haven't had a chance to fully test that.  I didn't want to fill my big cooler with ice water until I had a permanent place to put it, so right now I've only got the small cooler going.  I only had cold water and a single ice pack in there.  I suppose the air coming off is a few degrees cooler, but it's not anywhere close to a real air conditioner.

So how to build it?  Well, take a good look at the pics to start.  Here are the parts I used

1 18" commercial grade fan - $70  (it's a pretty nice fan...)
1 small pond pump - $20  (this one was 80 gph, and this seems to be a minimum)
25 feet of 1/4" OD flexible copper tubing - $5
12 feet of 1/4" ID PVC tubing - $2.50
1 foot of 3/8" ID PVC tubing $0.20 (I can't believe they made me pay for that...)
23 zip ties - $3 or less
1 cooler - $ as much as you want to spend (I'm using a cooler I already have)

Build cost tally:  $100.70 CDN

Now then.  How do you put all this together?  Well, I'll tell you.  Right now.

1.  Buy all the parts you'll need.  Fortunately for me, the copper tubing came in a 25' coil, so I didn't have to spend forever trying to make it into a spiral.

2.  Lay the copper coil on the face of the fan.  In my case, the coil was pretty much the exact same size as the face of the fan...  Handy!  Stretch out the ends of the tubing past the ouside edge of the fan, and center the coil on the fan.

3.  You will start fastening the tube near the center of the fan.  On mine, the copper starts about 3 inches from the very center of the fan.  The inside diameter of the coil is about 6.5", so you may need to bend the copper tubing into a smaller coil at the centre.

4.  Take a zip tie and loop it under the grille of the fan.  The best place to do this is where the spokes and circular wires are welded, attaching the zip tie cross-wise so that it cannot move horizontally or vertically.  You will start attaching the copper tubing at the point where it is just about to extend straight outward.  Fasten this zip tie tightly to hold the coil in place.

5.  The grilles are evenly spaced, and so can be used to evenly space the copper tubing as well.  The circular grilles on my fan were spaced at 1/2", so I decided to space the copper tubing at 1", or every two grilles.  Starting on the bottom half of the fan and moving outwards from the center, begin to lightly fasten the tubing to the grilles every inch or so.  It doesn't have to be neat yet.  Do not tighten the zip ties yet.

6.  After the bottom half is finished, move to the top.  Trace the grille closest to the center that the first bit of tube is attached to, around 180 degrees to the top of the fan.  Move up ONE grille (1/2").  This will allow the tubing to coil properly, and it will be properly spaced, too.  Attach the tubing at this point, again where a spoke and circular grille are welded.  Move outwards from this point as before.  Again, do not tighten the ties yet.

7.  Now it's time to make it look neat.  Starting at the center, begin adjusting the tubing so that it is always 1 inch apart from the tubing run before it.  When you get to a cable tie, tighten it.  In this way, move from the center point in a spiral all the way to the end of the copper tubing, adjusting for spacing as you go.

8.  You can add more cable ties at 3 and 9 o'clock if you like, but I found this isn't really necessary.  The coil is held tightly with just 14-15 zip ties.

9.  Trim off the excess lengths of zip ties.  The fan portion is done!

10.  Now it's time to rig up the pump.  The model I got is rated for 80 gph (gallons per hour).  This is just barely enough to move the water through 35 feet of tubing, so don't get a pump rated below 80 gph.  160gph would be more than enough.  Now, both the pump nozzle and 1/4" ID PVC tubing have an outside diameter of 3/8", so I used a short piece of 3/8" ID tubing to link the pump to the PVC tube.  I used cable ties to securely attach the tubes together.

11.  Cut enough 1/4" ID to reach from the cooler to the fan.  Don't use more than you need, because it will just be extra work for the fan.  Run this length from the pump in the cooler to one end of the copper tubing (I don't think it matters which end, I hooked it up to the center end).  Slide as much of the PVC tubing onto the copper tubing as you can, then seal it with two cable ties.

12.  Cut another length of PVC tubing to reach from the other end of the copper tube back to the cooler.  Again, slide as much of the PVC tube onto the copper tube as you can, then seal the connection with to cable ties.  The open end of the PVC tube leads back into the cooler.

13.  OK, time to check your work.  The copper tubing should be securely attached to the fan.  PVC tubing should be attached to both ends of the copper tube, and both end of the PVC tube should run into the cooler.  One of the PVC tubes should be coupled to the pump, the other PVC tube should be hanging open in the cooler.  All set?  OK, let's move on.

14.  Now it's time to fill the cooler with icy cold water.  You'll want to freeze a few blocks of ice in the freezer; if you have a large cooler then you can use 2L ice cream tubs.  You can also use reuseable ice packs.  Put the ice blocks in first, then fill the rest of the cooler with cold water.  Arrange the cables and tubes into a front corner (or punch holes in the lid if you have a styrofoam cooler) and close the lid as much as possible.  Don't pinch the water tubes!

15.  Now, plug 'er in!  Start with the pump.  You will see the air get pushed out of the PVC tube.  Soon after, condensation will start to form on the copper tubing.  You can plug in the fan now, and turn it on.  Does it feel cooler than before?  I hope so.

16.  Because of all the condensation (depending on the humidity), you may want to lay a towel or basin under the fan.  It will drip down, and it might make a mess!  If you use a basin, you can save the water and use it in your iron or something.

17.  How long the cooling effect lasts depends on how big the cooler is.  The bigger the cooler, the longer you can go before the water isn't cool enough to have an effect.

18.  Remember, you've got a fully functioning cooler right beside you.  Why not make it work double-duty to keep a few beers cold?  Now THAT'S efficiency! 


So there you have it.  The whole thing took me about an hour to build, including stopping to take pictures and change songs in iTunes.  It was quite easy to do, too!  So what are you waiting for??  Get yerself to the hardware store!

It is if you have a long enough extension cable. 

Alien wrote:

jeff-o wrote:

Yeah, I can make water ice in my freezer (or even scrape it off the shelves in there...)  I have to PAY for dry ice.

electricity is free where you live? Wow.

,xtG
.tsooJ

Well, the freezer is plugged in, and there is some free space in it.  May as well free up those spaces.




How well does it work?  Well, I still need a batch of 100% frozen ice blocks, rather than ice shells filled with cold water.  It is doing something though, because the water being returned to the cooler is much warmer than when it left.  And, there is a decent amount of condensation being formed as well, another sign that heat is being drawn out of the air.

$107 CDN?

My 'real' air conditioner was only $90US. Admittedly a bit more expensive, but still...

For $70, that had better be one helluva nice fan... I'd be afraid, though, that it might move the air over the coild too fast for it to bleed of a lot of heat - you'd end up with a lot of air that isn't much cooler than normal.

As a dehumidifier, it might be useful, though. About how much water are you collecting?

Oh yeah, and about "real" air conditioners...  My wife and I were all set to buy a real one, mostly for her benefit because she is very much a cool-weather person.  We are currently renting our house, so anything permanent was out of the question since we're only going to be here for another year.  That left the models that are installed in a window.  Unfortunately, all our windows slide left to right, not up and down.  We found a few models that would fit in our windows, but they were priced at $550 CDN and above.  YEAH RIGHT.  We didn't find any "in-room" air conditioners anywhere, either.

So anyway, we'll probably keep looking for some sort of cooling solution, be it a real dehumidifier or a real air conditioner.  We're just going to have to be really picky about fit AND price...

Mars_Attacks wrote:

They're everywhere and cheap down here!


At Sam's Club you can get an indoor unit that exausts out the window with a hose system.

if by cheap you mean above $300 USD.... then yes.
if its cheaper than that, then it probably isn't an air conditioner, its probably a swamp cooler.

Mars_Attacks wrote:

They're everywhere and cheap down here!


At Sam's Club you can get an indoor unit that exausts out the window with a hose system.

I'm actually thinking of getting one of those - but slightly different.

It comes with a kit to install the exhaust into the wall. So you get several kits, and move the unit to whatever room you happen to be in.

Mars_Attacks wrote:

They're everywhere and cheap down here!


At Sam's Club you can get an indoor unit that exausts out the window with a hose system.

Yeah, that's what I need, but I could not find any stores that sold them.  I briefly consitered altering an in-wall air conditioner by adding a box around the exhaust and running a hose from there, but I don't think my wife liked the idea.  Heh, she would probably go for it if I knew it would work, though.

jeff-o wrote:

Freezer mac wrote:

KoolerAire Link

a HA!!!

Kooleraire wrote:

Simply fill your Igloo 25 quart or Coleman 28 Quart cooler with ice, insert KoolerAire just inside the top, plug in the car adapter plug and enjoy cool, crisp, refreshing air for hours without altering your coolers capacity!

This is still a form of evaporative cooler.

What the home made air conditioner people are missing is the fact that an air conditioner not only vents hot air and heat generated from the unit itself, but they also dehumidify.

It's unseasonably humid out here in the desert this week, and with our swamp cooler going, 82

mtpalms wrote:

jeff-o wrote:

Freezer mac wrote:

KoolerAire Link

a HA!!!

Kooleraire wrote:

Simply fill your Igloo 25 quart or Coleman 28 Quart cooler with ice, insert KoolerAire just inside the top, plug in the car adapter plug and enjoy cool, crisp, refreshing air for hours without altering your coolers capacity!

This is still a form of evaporative cooler.

What the home made air conditioner people are missing is the fact that an air conditioner not only vents hot air and heat generated from the unit itself, but they also dehumidify.

My little brother has to have a humidifier in his room at night or he risks getting a bloody nose.
When he comes to my house - the swamp cooler does that for him

resedit wrote:

mtpalms wrote:

jeff-o wrote:

Freezer mac wrote:

KoolerAire Link

a HA!!!

This is still a form of evaporative cooler.

What the home made air conditioner people are missing is the fact that an air conditioner not only vents hot air and heat generated from the unit itself, but they also dehumidify.

My little brother has to have a humidifier in his room at night or he risks getting a bloody nose.
When he comes to my house - the swamp cooler does that for him

Me too...  I haven't had a bloody nose due to (lack of) humidity since the spring.  We run a humidifier in the winter so I don't die due to massive blood loss overnight.

Additional note. The water from the dehumidifer would be used to water plants and solar heat techniques using mass will help supply the night time heat..