How to Make a DIY Swamp Cooler - Backyard Boss
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How to Make a DIY Swamp Cooler

Swamp coolers are an affordable and easy to make alternative to expensive air conditioners, central air units, and ceiling fans. When it comes to DIY products that help you beat the heat and keep your house cool, all fall short in comparison to the DIY swamp cooler.

In this piece, we teach you exactly how to make a DIY swamp cooler, as well as share tips with you about how to get your new cooler to run at its absolute coolest temperatures possible.

Making a DIY Swamp Cooler

Swamp coolers work on the simple but effective method of evaporative cooling. That means they require a minimum of three things to function properly: water, dry warm or hot air, and purposefully directed airflow. The DIY versions also rely on water, ice, and a breathable piece of cloth as well.

Most DIY swamp coolers consist of a five-gallon bucket or similar-sized container with a lid and two “holes.” One hole is for the intake of fresh warm or hot air through the lid, the second hole (more likely a series of holes) is for blowing the cooled down air back out through the sides.

    5 Gallon Bucket

White plastic bucket.
    We recommend a simple five gallon plastic bucket with a lid. If you don't have one you can spare, try this bucket from Amazon.

Inside the swamp cooler, a cloth is fixed over the exhaust hole(s) as a sort of filter. These are typically referred to as pads. The pad soaks up water from the bottom of the cooler, which should be nice and cold, and as the fan continues to pump fresh hot air into the cooler, this fresh air is forced through the cool damp cloth which rapidly lowers its temperature.

Step One: Gather Tools and Supplies

The first step to completing your DIY swamp cooler is an important one as you can’t get started until you have gathered up everything you need for the job. The main things you will need include:

  1. A bucket or large container (one that you can easily modify with basic tools; we suggest a five-gallon bucket of plastic or foam)
  2. Drill (or razor/knife if you are using a foam container)
  3. Adhesive (glue, caulking, or heavy-duty tape)
  4. A small fan (one that can be permanently sacrificed for the greater good)
  5. Water
  6. Ice (cubes, as well as crushed if possible)
  7. Cloth (a small towel-size cloth, preferably one with a breathable material)

Depending on the exact design you are personally going for, your list of tools and supplies may differ a bit.

    Honeywell HT-900 TurboForce Fan

Small Honeywell fan
    Need a fan to power your DIY swamp cooler? This small but powerful Honeywell fan should fit into the lid of your bucket.

For an advanced DIY swamp cooler, you could add a pump and a soaker hose to actively moisten your cloth.

    Pulaco Mini Submersible Water Pump

Small submersible water pump
    This water pump can power a soaker hose that keeps your cooling pad or cloth soaking wet.

Step Two: Prepare the Cooler’s Body

One of the biggest steps to putting together this cooler is preparing its body. The first thing you need to do is remove the lid and set it to the side. Next, decide how many holes you want in your cooler, and how large you want them. Most people stick with a couple of large holes in the middle of the body or a series of much smaller holes concentrated in one area. You can do this with a knife, drill, or screwdriver, depending on the material you are working with.

Step Three: Attach the Fan to the Cooler’s Lid

Once the holes in the cooler’s main body are done, measure the front of your fan and cut out a big enough hole for it to fit into the lid. Make sure the hole is a flush fit or else the fan will fall into the cooler and short out once it hits the water. After the fan’s face is placed against the hole, apply whatever adhesive you are using to the edges (this could be tape, glue, or even caulking). Leave the adhesive to dry if necessary before moving on to the next step.

Step Four: Put It All Together and Try It Out

With holes in the body and the fan attached to the lid, it’s time to make sure everything fits together. If anything is loose or there are gaps around the lip of the lid or elsewhere, patch things up before moving on. Once all the parts have been placed back together and you’ve plugged it in to make sure the fan is working and the air is freely flowing from the soon-to-be swamp cooler, you are ready for the final step.

Step Five: Add Water and Ice and Put It to Good Use

Fill your new swamp cooler up with water and ice, making sure to cover the holes with the cloth that you have found for it. You may need to trim the cloth down to better fit both over the holes and inside of the container. After your cloth is situated, and the water and ice have been added, you’re good to go. Now it’s time to enjoy the fruits of your labor and cool off.

How to Make Your Swamp Cooler Colder

But, wait, there’s more! Now that we discussed how to build a swamp cooler from scratch, let’s talk about how you can help it produce even colder air to help keep your home cool. Below are five simple but effective tips to consider:

Use Extremely Cold Water

The first tip is a simple one: Use the coldest water possible when filling your swamp cooler. Fill containers and chill the water in the freezer before adding it to the cooler. If you can, make a slush by adding crushed ice to the water as well.

Replace Ice Often

Speaking of slush and ice, to keep your swamp cooler as cold as possible, you need to add ice to the water and replace it often. We suggest using crushed ice and water, as well as adding ice cubes as often as possible. One to two dozen ice cubes is preferable.

Keep the Light Off

Another basic but powerful tip for getting your swamp cooler to run at its coolest is keeping it in an area without direct light. The principle is simple: light causes heat, the heat melts ice and raises the temperature of the water. In the absence of light, the contents of your DIY cooler (water, ice, and wet cloth) are likely to stay cooler for a longer period of time.

Use It With a Dehumidifier

    ALROCKET Dehumidifier

Small portable dehumidifier with water collection tank.
    This compact portable dehumidifier can remove moisture from the air, making it feel more pleasant and increasing the effectiveness of your evaporative cooler.

Evaporative (swamp) cooling works better with dry air. If you don’t live in a dry climate, a swamp cooler may not be effective. A dehumidifier not only increases the effectiveness of your swamp cooler, but dry air also feels less hot (or cold), making it easier to tolerate the heat.

Try Dry Ice

Depending on the design of your swamp cooler, especially because it is a DIY model, there may or may not be a spot inside it for dry ice. However, if you’re curious enough what a difference it may make, you can always drain your swamp cooler of liquid, wipe it out, and add dry ice for a test run.

Building Your Own DIY Swamp Cooler

If you’ve decided to make a DIY swamp cooler, hopefully, our article has helped you to realize just how simple of a concept that it is, and how easily one can be crafted at home, regardless of experience with such projects. Along with the simple instruction listed above, all you need to get started is a bucket, drill, and small desk fan. So, what are you waiting for?

Not sure about building a swamp cooler just yet? If not, you may be better off taking the slightly different approach of building a DIY air conditioner instead.