DIY Air Conditioning Fan

A homemade air conditioning fan.
  • 2-4 hours
  • Intermediate
  • 50-200
What You'll Need
Floor fan
Drill and bits
Fountain pump
3/8-inch plastic tubing
3/8-inch 20-foot copper coil
Zip ties
Pipe clamps
Spray paint

It sounds like magic, but it's actually possible to turn a garden variety floor fan into a DIY air conditioning cooler. In a nutshell, the mechanism involves pumping ice-chilled water from a bucket through a coil attached to the front of the fan. The fan then pushes air across the coils, exchanging the cold from the water to the air, and the water returns to the bucket to get cold again.

Step 1 – Find a Container

The whole thing needs a single footprint, so the fan will stand inside the container. Finding that container depends on your decor and a little hunting.

DIY Air Conditioning Fan, Justin DiPego

I came across a fiberglass planter in a classical style that will go well in my place. You could use anything that’s big enough and will hold water, like a zinc bucket, a vintage milk can or a sleek, modern trash can.

Step 2 – Find a Fan

I had an old floor fan in the back of my shop I knew I could use.

DIY Air Conditioning Fan, Justin DiPego

It was in rougher shape than I remembered, so I disassembled it and replaced the stand with a 48-inch black pipe nipple and spray painted everything black.

DIY Air Conditioning Fan, Justin DiPego

You won’t need to do this if you start with a better fan.

Step 3 – Secure the Fan

Set the base of the fan in the bottom of the container. This will depend on what fan and container you use. My original plan was to trim the feet of the original stand to fit the bottom of the container and then screw it down. This would have worked if the rest of the stand was in good shape. Instead, I screwed a floor flange to the bottom of the container and then screwed the pipe to the flange. In any case, seal everything with caulk.

Step 4 – Attach the Coil

Remove the safety cover from the fan and place the copper coil on top of it. The copper coil comes already in the proper shape. You just need to bend one end so it extends out from the center just past the outer coil.

DIY Air Conditioning Fan, Justin DiPego

Starting from the center, secure the coil to the cover with zip ties. Use the flexibility of the coil to keep it even, so it spirals nicely out from the center to the edge. When you get to the end bend the outer end of the coil to where you want it and cut it if you need to. In my case, I wanted both ends on the same side of the fan, but you could put them on opposite sides, or bend them around so the attachments are hidden. Put the safety cover back on the fan.

DIY Air Conditioning Fan, Justin DiPego

Step 5 – Secure the Power Cords

You could have the power cords hang over the side of the container, but I wanted a cleaner look. To achieve this, drill a hole in the side of the container just large enough to admit the plugs for the fan and pump. If you’re lazy (like me) this will be about a 1-inch hole, but you could drill a much smaller hole if you take the time to cut the plugs from the cords and replace them after you pass the cords through. The smaller hole requires only caulk to seal it. I sealed the larger hole with spray foam.

Step 6 – Attach the Pump and Tubing

The pump itself determines the diameter of the plastic tubing and copper coil. My pump required 3/8-inch inside diameter so that’s what I used. Attach one end of the tube to the outlet of the pump and the other to the copper coil. Secure the tube and coil connections with pipe clamps.

DIY Air Conditioning Fan, Justin DiPego

Run another length of tube from the other end of the copper coil down into the container. The water will run up from the pump, through the coil and return to the container through the other tube.

Step 7 – Fill With Water and Ice

DIY Air Conditioning Fan, Justin DiPego

I placed 6 16-ounce frozen water bottles in the container and then filled it with water. Next time I fill it I'll use more frozen bottles and less water.

DIY Air Conditioning Fan, Justin DiPego

Turn on the fan and the pump and the ice chills the water that circulates through the coil, bringing the temperature of my home office down to a level comfortable enough to actually get some work done.