This is shared by Melinda Jansson with permission.
In July my wife helped her parents who are in there 90’s giving her sister a break. We were in an upstairs bedroom with out air conditioning, which sent me on a quest for cooling that would work there and also be compatible with camping in the summer months. It also needed to be added to our 72-hour kit. (We live in St George, Utah).
After building several that really were not up to the challenge, I have arrived at one that works great. It is based on a water chiller, which is used to cool high-rise buildings.
If you get a five gallon bucket that is translucant you can see how much water is in
the bucket at a glance so you don’t run the pump out of water. (I got mine from
Most of the parts are from Home Depot or Lowes. I purchased the 200 cfm computer
fan, 240-liter fountain pump, and 12-volt cigarette plug from Amazon.
Begin by cutting the cooler pad 13 inches by 30 inches, cut second section 13 inches
by 24 inches.
Silicone 13” by 30” ends together.
Put together and tape to hold in place while curing.
Place shorter piece inside glued roll; leave inside about 1 inch taller than outer one to help form a better seal to lid.
Cut hole out of Home Depot lid, use the 3 7/8 “ inside dimension toilet flange (Lowes) to mark cut out. I have used a utility knife to cut round circles around the bucket before I had a 3 ¾” hole saw.
Bolt fan to lid using 4 - 2 ½ inch 8/32 screws used 4 small washers and lock nuts to attach toilet flange. Carefully cut part of lid that over hangs fan.
Cut the 3/8 inside dimension vinyl tube to fit outside pad. The T connector should be cut shorted so the holes in the tubing will be close enough so there won’t be a dry strip on the pads. Use a hot nail or wire (10 gage) to burn holes in vinyl tubing. Holes should be about ¾ inch apart.
Solder the fan and pump wires together with the 12-volt plug (I like to make one up
and make it longer, It costs a little less than the pre-built).
Shrink tape the joint. Slip pump on tubing add water and test. I found some 5-inch Aluminum tubing, which I can vent into the tent or camper or van. Bucket goes on outside of tent or room and forces cold air into tent or room. An open window on the other side of the tent or room will exit warm air out. The cubic footage of the space to be cooled needs to be replaced every 3 to 5 minutes.
I would be happy to answer any questions and give any help I can. I have built about 10 of these in the past month.
This placed on a chair we were able to keep us cool in bed.
Force cold air into the room from
the outside. (Amazon sales 8ft length 5" Aluminum Flexible Duct)
I picked up a igloo 12-volt inverter at a thrift store for 3 dollars to run in the house. But it only runs at 12 volts, so slower than the solar generators.
My Solar wave 240 is a lithium iron phosphate 20ah -14.2 volts and runs the cooler for 11 plus hours $299.00. (a store in St George)
My Goal Zero Sherpa 100 lithium iron phosphate 8ah – 14.2 volts and runs the cooler for 5 hours $349.00
I am done buying Goal Zero
When its 100 degrees the cooler puts out 67 degrees and the water inside the cooler is 59 degrees (a great cooler for milk or a soda pop).
Cost of the parts is plus or minus $80.00