Introduction: Keep Me Cool Portable Air Conditioning Cooler 120V

Picture of Keep Me Cool Portable Air Conditioning Cooler 120V

I have always wanted to have Air Conditioning  in my shed, I mainly use it for storage, but I am always in there looking for something!  I was also looking to have something I could take with me, wherever I go, like to a friends house if we just hang out in the garage of on the deck.  I really don't like warm weather, so here is my keep it cool answer!  This project draws a lot upon other 'ibles, like CameronSS's idea, but I needed it bigger!  This all runs off 120V, so I don't have to worry about batteries, just bring the cooler and a long extension cord.   I bought as few materials as possible, and I only have about $20 into this project (aside from what I dumpster dove for or otherwise had laying around),  I probably could have gotten away with about $10, but I wanted a few options that I was willing to pay for.

Step 1: Gather Stuff

Picture of Gather Stuff

Here is what you will need:
- Cooler (found mike kicking around my shed)
- Couple of larger AC fans, I got mine from a K&N Air Filter display that my local Auto Parts Stores was throwing out when they were going out of business
- Coil setup from a Fridge that is being discarded.  Keep an eye out in the neighborhood on garbage day.
- Old Air Purifier fan, or any 6ish inch fan that you can find
- Toilet Drain Flange, Hardware Store (Orange, Blue or Green)
- Shower Drain, again found at a Hardware Store (Orange had this one)
- Fountain Pump, Harbor Freight.
- 7" Duct Elbow, Hardware Store

Misc tools
Angle Grinder
Jig Saw

Step 2: Prep the Fans

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I started by breaking apart the K&N display, and I left the surrounding plastic parts on there.  It helped with the mounting!  I then took apart the Air purifier, and removed the motor.  Sorry, I don't have more pics of this step.  But in order to easily mount the motor, I used my angle grinder and ground away the plastic except for the actual 'mount' holder.  It fits nicely into the Shower Drain.  You will see this in upcoming steps.

Step 3: Hack the Cooler

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Now that the fans are out of the large case, I took a piece of cardboard and outlined a hole slightly bigger than the fans, but still smaller than the surrounding plastic.  I also cut a hole for the toilet flange to fit into.  I also, when I was done, fully removed the underside ribbed portion of the cooler, it just makes everything easier to work with.

Step 4: Load Up the Fins, Fans, and Flange

Picture of Load Up the Fins, Fans, and Flange

Amazingly, the fridge fins fit almost PERFECTLY under the hood!
I snared some 11/32 PCV hose, from the same parts store that was closing, and hooked it to the trimmed ends of my fins.  One for the uptake, and one for out.  I didn't want to be distracted all day with the sound of the water dripping out, so another hose should allow the output to flow under the water line.
The pump just sits in the bottom of the cooler using suction cups, and I cut a hole in the top of the cooler to allow the power cord to come out.
I decided to hold up the radiator fins in the lid by using some 6MM threaded rod (had it in stock).
I simply cut it to length across the lid and 'threaded' them to hold the unit up.
I mounted my fans and my flange.
The fans will blow down into the cooler.
I cut a hole for the power cord from the fountain pump.
note, I found some Peel-N-Seal caulking on clearance at my local hardware store, so I picked it up.  This way, I can caulk everything and if I see I did something wrong, or want to re-do something I can just peel up the caulk.  As you can probably tell from the pictures, the caulk was pretty old, and about half set in the tube.  I had to cut the tube open from the side and just work it like play-doh

Step 5: Hook Up the Pump

Picture of Hook Up the Pump

Here Is how I hooked up the pump.  I just cut off the ends of my fins and hooked up my PCV hose.  I then connected the end of one of the hoses to the pump, which just mounts on the bottom of the cooler with suction cups, to the pump outlet, and secured with a hose clamp.  It seemed a little loose.

Step 6: Add the Drain and Exhaust Fan

Picture of Add the Drain and Exhaust Fan

I just took apart the air purifier, and used my angle grinder to trim away any excess plastic.  I trimmed it to fit almost perfectly across the drain opening, and let enough of a "tab" to reuse one of the drain screws, easier to mount!
I then mounted the fan, and gorilla glued the speed control knob to the other side.  I got out my liquid electrical tape and gave all the connectors a good coat around the edges, 'cause that's how I roll.

Step 7: Add Duct and Get Ready to Roll!

Picture of Add Duct and Get Ready to Roll!

I added my 7" adjustable elbow, I had to cut the bottom portion open, I just drilled out the rivets, so it could fit nicely inside.  I caulked the rim of the flange with more of the Seal and Peel Caulk, mounted the fan and drain assembly, then added ductwork.
Since I drilled out the bottom section, I got it to be a nice tight fit, then just used two sheet metal screws to hold it together.  I didn't go too tight, this was it is still adjustable.

Step 8: Chill

Picture of Chill

Now fill the cooler with cold water and Ice, and Chill!
So far so good!  Nice and cold, but it's only been mid 80's outside, so about 90 in the shed.  I guess the real test will be when it's over 100!
My only concern so far is that the 158GPH pump may not be enough.  They make a 260ish one at Harbor freight, so I may have to upgrade to that in the future!

Step 9:

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It's been a while but I have some rough figures....

The ambient temperature in my shed lat summer was 112F

I could not do a cool down estimate as the door was open because I used this to cool my equipment for an outdoor move theater.

using 2 - 15# bags of ice I was able to produce a "cool factor", cold air blowing at 42F out of the cooler for a duration of at least 8 hours, we finished the movie and went to bed after that, so it may have been longer...

this is a nice option for equipment cooling!


T0BY (author)2015-08-03

Very clever, you've got it working really well!

Norsefalconer (author)2011-08-25

I don't know where you're located, but if you have another coil/heat exchanger, you can dig a hole 6~8ft down, drop the coil in there, fill with sand or gravel (dirt may even work) and have a budget geothermal unit. Across most of the US, it's around 65 deg that far down. Could be a "heater" as well in the winter. If you go to you'll find a REALLY informative, technical paper/article on how to do this for an entire house w/ air or water as the exchange medium. There's a map showing avg. ground temps West of the Mississippi (he's focused on CA). I know, (expensive) commercial systems exist, but this IS a DIY site right?

etcmn (author)Norsefalconer2013-09-09

This comment is a great idea but you only need to dig half that deep. In most areas the ground temperature will remain stable just 3-4 deep.

Thanks for the great link, I'll look into that more, but I just got inspired to do a quick cooler! yeah, this IS a DIY site, and using stuff you have laying around or dumpster dove for is half the fun!

PACW (author)2011-08-25

Very nice! We have an orange and a blue hardware store here in Arizona but the last green one we had was O'malleys and they went under 25 years ago or so. Are they still around in other parts?

etcmn (author)PACW2013-09-09

Menards is still thriving in the Midwest. Not too surprising as their home base is in Wisconsin. I used to live in Minnesota, move to central New York five years ago. Menards is one of the things I miss most.

digitalmonkeyman (author)PACW2011-08-25

I refer to "Green" as Menards, although I guess it could also mean Orchard Supply in other parts of the country. O'Malleys is gone as far as I know, just like Handy Andy, wow, a trip down memory lane!

tzsch (author)digitalmonkeyman2011-08-25

We had Handyman out this way (Northern California). Good times

etcmn (author)2013-09-03

Love this idea. Would like to see a version I could power with the 18v batteries from my cordless tools. I'm planning a move driving cross country and need something to keep my pets cool in the truck when I stop for meals.

ekbruster (author)2011-12-29

Very Cool, thinking I need to do this with some 12v computer fans and a 12v pump hooked up to a solar panel, that would be awesome for those days out at the campsite!

showbizkid83 (author)2011-08-31

I have been looking for something like this for a few years now for you see i am a letter carrier in Texas and we drive trucks with nothing but a small 6 inch fan to cool the cab. This would be perfect for me as I have a mounted route where I deliver curb side boxes all day. Here is an idea. Has anyone thought about using dry ice for cooling.

Caleb93 (author)showbizkid832011-09-21

Dry Ice used as a coolant for the system would be very dangerous unless you have your window open. Dry Ice is solidified Carbon Dioxide after all.

Bednarz (author)2011-08-29

I take that back...I see now that the air is cooled before blowing over the ice, I'm still curious about the humidity though.

Bednarz (author)2011-08-29

Nice work! I had originally been thinking that you'd gone a little overboard, but I like the end result. A couple things:
Your only real concern with an overpowered pump is if it's generating a lot of heat and pumping warm water up into your heat exchanger and/or melting the ice too fast. The idea is to keep your fins as cold as possible so the more cold water you move through it the better.
Don't run de-ionized water for any length of time. De-ionized water has a habit of trying to pull ions from whatever it's running through, speeding up your corrosion issues.
Instead of salt, add some alcohol to your mix (grain or rubbing) it has the same temperature lowering effect but won't corrode. The pump has a warning about being used with fuels, but if you keep the mix reasonable it shouldn't be a problem.

I'd be interested in hearing what this set up does to the humidity in your shed, since you're blowing warm room air over the ice before blowing it over your fins.

Er. Arun (author)2011-08-27

nice one

_Scratch_ (author)2011-08-27

Use distilled water, that will keep calcium build-up away. Use a bit of antifreeze if you don't drain it too often. Another thing would be to add about a handful of salt to the water, it may corrode the pipes faster, but it would drop the water temp, and the ice would melt faster. For cleaning the pipes out, just use vinegar, let it sit for 5 min, then wash it out with distilled/deionized water.

wblack3 (author)2011-08-27

Nice work, but I can't figure out where the cooling effect is coming from other than the ice originally placed in the device.

Lindie (author)2011-08-26

That's a great idea. It's really COOL!!!

lucky3448 (author)2011-08-26

nice.. but it will not work long time because calcium in water will deposit after every time u pour water and start choking the radiator.

trike road poet (author)2011-08-26

Love the idea here, garage engineering is always fun!
I'm building one of these in a 12 volt mode for my pickup, to sit on the back seat.
Cool the truck cab while driving and not use the fuel hungry Auto AC. With only two computer fans and a small submersible pump to run, this will use a lot less power then the Auto AC electric clutch, and less fuel to make the few extra watts of power to run the cooler. Add in a simple valve and hose to drain excess melt water outside the cab means not having to haul it out to drain it and straining the back.

Will detail the build and make an instructable when its complete. Will also test it against auto unit for cooling. I intend to put the coil outside the ice container to cool cab air and not introduce extra humidity to the cab, dripping enough sweat now! By channeling cab air only through the cooling coils, I can have dry cool air and no extra cab humidity do deal with.

Its the ones who try things that find answers, and no amount of armchair design beats a hands on trial and error for building real knowledge. thankfully here at instructables, we can learn from each other.

Sitnalta (author)2011-08-25

The 158GPH pump is probably what you want. You don't want the water flowing too fast otherwise it'll shoot through the radiator faster than the heat can be exchanged.

Though to be honest, I don't think you need the pump/radiator at all. Blowing air over bare ice is going to be more efficient. That's how old-style air conditioners worked before phase-change systems took over.

I have a 92GPH pump left from a fish tank, maybe I should try that one too. Do you think slower would be better?

shortcowboy (author)2011-08-25

Use a Evap. Cooler pump. Better Water Flow cheap to run, You did good on your design, I built mine with basic same design only I Used an old heater core from a VW, Evap pump and a 90 degree dryer vent for my exhaust return. In Az. My 10x12 shed stays around 78/79 for about 2 hours before I have to re fill the ice. But Very nice job on Yours!

Thank You! How much ice do you use in those 2 hours?

about 15 lbs (3) 5lb bags from our little store up the road.

I'll have to do tests with both cubes and block. Thanks for the tip!

use block ice.

JakeBlanton (author)2011-08-25

If you already have 110VAC at the place you are trying to cool, just buy a cheap window air-conditioner. This type of system is most useful for places that you don't have 110VAC. Of course with that type of system, you modify it to use 12VDC fans and pumps instead.

I agree, but an 'ible about carrying a window A/C unit to my shed and plugging it in would be sort of boring... :-)

Pa1963 (author)2011-08-25

It's pretty awesome, but I think it's a little over engineered. Why not just throw some ice in the cooler. Fans blow in hot air, vent lets out cold air. Voila!
Nice jon though. And nice score on the free fans. Dumpster Diving Rules!

digitalmonkeyman (author)Pa19632011-08-25

Over Engineered? Heck Yeah! I love it though! even if it doesn't help the cooling aspect, it looks cool and recycles lots of 'dumpster' parts, my kids call it Sailing...
during the day it's Garage Sailing, and at night, it's Garbage Sailing

Sailing.. :) Kinda make me want to break out the Caviar and Champagne!

greeneprojects (author)2011-08-25

Very nice work! I like every aspect of it.
I would love to see some performance data on it that would list the sq. ft. of your shed and cooling gain.
Thanks for making this instructable.

thanks! I will measure up my shed and get some more data soon! I hope to have my very amateur video up in a day or so..

l8nite (author)2011-08-21

I really like this build but as with the others I don't understand the need for all the fans, one (or in this case 2) blowing into the closed box will force the cooled air out the other opening without the need of the fan pulling air out. Lets assume that your double fan flows 5cfpm into the box, the single fan flows 3cfpm, the single fan wont be doing anything escept blocking air flow. Maybe Im wrong but the sysytem should work just fine with only air being blown in OR sucked out.

realy inspiring "ible"

digitalmonkeyman (author)l8nite2011-08-22

Thank You l8nite. Is there a need for both the intake and output fans? I'm not sure! Here is my tested theory, with absolutely no empirical data behind it.

I tried it by only having the input fans blowing, and yes, the output fan does turn on its own, but I 'feel' more cold air coming out when they are both on. I also tried it with just the output fan, and yes again, the intake fans turn from the suction, but I just don't 'feel' as much cold air coming out. And since it is not a completely sealed section around the fans, I can't imagine that the cfm would be blocked, as some air should be able to get around the fan and it's capacity.

Without studying the physics of it, and measuring the actual airflow, I have to compare it to driving to work in the morning. I can sit in traffic on the expressway at 10mph, and be to work in 50 minutes, or take the side roads, get there in an hour, actually travel twice as far mileage wise, but feel better, because I "felt" movement!

It's all in my head!

This design is good!
L8nite is correct about your fans but you also have a point as well digitalmonkeyman. How can that be, see below!
It looks to me that your mount for your cold air exhaust fan restricts the airflow from the cooler. You have a hole about 1/5 the diameter of the overall exhaust vent for air from inside the cooler. And the area of your intake is greater than the diameter of your overall exhaust vent. This:
1) Reduces the efficiency of your intake fans & coils as the air has to go somewhere if it can’t get into the cooler, if it does go into the cooler it is being forced out other ways than your cool air exhaust port. For example the seams of your lid.
2) Reduces the flow of cool air exiting your cooler. Although you can increase the pressure of the air going out an opening you cannot increase the maximum SCFM or flow of that opening.
3) Increases the time to cool the area you are trying to cool because you’re not moving as much cool air from your system into the room.
Some increased pressure is good. This will increase the force of the air from your cool air exhaust. Expansion of this compressed air also provides added cooling, but this would not be noticeable due to how low a pressure drop created across the exhaust vents opening.
Any flow across a good fan will make it turn however. This does not indicate the SCFM of the air but more the force/speed against the blades resistance.
A plastic bag however would be a better indication of both flow and force. Force being how straight the bag stands and flow by how full the plastic bag is.
So why do you feel more air flow with the additional fan? Not because you are moving more air from inside the cooler but taking ambient air from outside it and blending it with the cool air.

Transquesta (author)l8nite2011-08-22

I don't know whether the addition of the exhaust/output fan was an 'intentional' part of the design, but it is nonetheless brilliant. The 'input' fans increase the static pressure within the enclosure thus making more cool air available to the output.

Agreed, that could be a problem if the rated CFM's of both fans aren't more or less equal (or the input fans' rated CFM's are greater than the output), but if they're compatible in this respect then the output fan should be a real benefit to the sensible cooling effect of the device. It has the effect of serving as a 'booster.'

Is there a way to test the CFM of the fans? For a guy who isn't a HVAC guy?

Yes, you can buy a 100+dollar anemometer with a CFM calculation function or you can hazard a guess using a small kitchen bag. The fan which fills up the bag first produces the greater CFM. :-) Seriously, for a project like this I'd go with the kitchen bag--IF you're really curious. (FWIW, there MIGHT be a rating stamped on the sides of either/both fans, but I wouldn't count on it.)

pribeiro2 (author)2011-08-25

Awesome job, man! I have the exact same cooler.. once I upgrade it I'll really consider trying this out. Congrats!

movelikewater (author)2011-08-25

Thanks for the design. I think it is inappropriate to claim this is a $20 project. Your list parts you "found" are well over $100. You should be honest about the value of parts for the people that aren't living next too a junkyard/already have a stocked shed.

Treebeard2007 (author)2011-08-25

So how long does your Ice water last in the cooler?

I just did a test, and with 14# of ice, I was able to drop the temperature in the shed 10 degrees F. The shed started at over 100, and I was able to get it to about 90, before the ice only melted completely. Which was about 25 min.

I have a video I will be posting soon.

ak08820 (author)2011-08-25

Latent Heat of Fusion of Ice = 144 BTU's per pound
The smallest AC units are about 5000 BTU/hour.
The cooler may hold about 20-30 lbs of ice.
So, the heat it will absorb will be about 144 * 30 = 4300.
So you may get about an hour of usable cooling from this.
Hauling ice to the shed may require more cooling.
I would rather troll CraigsList for a free AC unit.

WinbookXL3 (author)2011-08-22

make a video of it plz

Transquesta (author)2011-08-21

Of all the DIY 'cooler systems' I've seen, this is the most efficiently designed. Nice work!

You could use a few more panes/images relating to the installation of the pump, though. :-)

Thanks! I added an extra step to show how I hooked up the hoses and pump. I hope it helps!

It does/did. I'm an HVAC guy, so I pretty much understood the role of each part in the assembly, but not everyone who may see it will have the same degree of experience. :-)

About This Instructable




Bio: I am a Home Theater Nut, Gadget Guru, Builder of Things, and I'm getting Much Much better at putting things back together after I ... More »
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