How to Build Swamp Coolers

Cut the 30 inch by 36 inch cooler pad into three 15 inch by 12 inch sections.

Set the table saw to a depth of 1/4 inch and run the PVC pipe over it lengthwise to create an open groove completely through one side.

Insert two of the pads into the grooved section; if you can fit more in, go ahead, but two is usually the maximum. Make sure the 12 inch side is inserted, not the 15 inch.

Epoxy the curtain rod hangers onto the box fan as close to the edge as possible so that the hook end hangs over the back of the fan box.

Set the PVC pipe with cooling pads on the curtain rod hanger hooks.

Set the fan up near an open, screened window.

Fill the 5 gallon bucket with cold water. Insert a piece of aquarium tubing into the bucket. Attach the other end to the small electric pump.

Run another piece of aquarium tubing from the exit valve on the electric pump up to the PVC pipe. Thread the aquarium tubing into the pipe about 3 inches. Epoxy this tube in place.

Run a length of string from the end of the PVC pipe down between the cooling pads and back into the 5 gallon bucket. Make sure the string doesn't bow and the lowest point of the string is in the bucket. This will wick water that soaks all the way down pads back into the bucket and eliminate the need for a drip pan.

Adjust the rate of flow on the electric pump so that the pads stay wet enough for the fan to draw cool water through it and pass it into the room.