How To Remove Rust From An Evaporative Cooler

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Due to any hot weather, many people consider an evaporative cooler a must-have appliance. These coolers are perfect for keeping your home or apartment cool all year round and without drastically increasing your energy bills. However, they can be prone to rust from time to time. We’ve researched how to remove rust from your evaporative cooler, and this post will discuss it.

Here are the steps to remove rust from your evaporative cooler:

  1. Turn off the power to the cooler
  2. Spray the cooler down with water
  3. Spray rust cleaning solution on the cooler
  4. Rinse off the cooler
  5. Repair extensive damage
  6. Sand down the epoxy

The best approach to prevent rust from accumulating inside your cooler is to create a maintenance plan. It also means taking a few extra steps when preparing your cooler for use. Continue reading to learn more about how to get rid of the rust and prevent it from accumulating.

Close up shot of a grungy old thrashed swamp cooler as found in a junkyard in the middle of the desert, How To Remove Rust From An Evaporative Cooler

What Causes Evaporative Coolers to Rust?

Rust on your evaporative cooler is usually caused by humid air finding its way onto the cooler surface and inside its interior. Metal will typically rust in high humidity conditions, and in some cases, stainless steel can as well.

If you notice orange-tinged stains developing on your cooler, chances are it’s beginning to rust. Unfortunately, this is just a natural process of the oxidizing effects of water.

Also, in some areas, the tap water is rich in minerals such as calcium and magnesium and this can cause alkaline deposits to be left on the cooler’s interior and cooling pads. If these deposits go unchecked, they can cause corrosion of the metal housing inside the cooler–which is no good.

However, you can prevent rust from occurring, though you may need to replace your evaporative cooler in extreme cases. Proper storage also plays a part in the accumulation of rust. But, we’ll discuss this more in detail later on.

Steps To Remove Rust From An Evaporative Cooler

An evaporative air cooler placed on the side of a house, 14 Types Of Evaporative Cooler And Brands To Know

Before attempting to clean the rust from your cooler, it’s best to make a quick list of the cleaning materials you need to get the job done. You can use both commercial rust removers and all-natural solutions. Let’s take a look at them.

Things you’ll need:

  • CLR
  • Lemon juice
  • Baking soda
  • Distilled vinegar
  • Cleaning cloth or sponges
  • Water hose
  • Bleach
  • Scrub brush
  • Paint scraper
  • Water
  • 2-gallon bucket
  • Sandpaper
  • Rubber gloves

1. Turn off the power to the cooler

Before doing anything, disconnect the cooler’s power plug. Also, turn off the cooler’s water supply and drain all the water from the bottom pan. Next, remove the exterior pads and panels.

2. Spray the cooler down with water

Then, take a garden hose with an attached sprayer and spray down the cooler. Be sure to get the interior and exterior so that you can remove any dirt, debris, or dead insects from the surface of the cooler.

Read more details about this garden hose on Amazon.

3. Spray rust cleaning solution on the cooler

Now, grab your rust cleaning solution and apply it to any areas on the cooler that have rust stains. Pay special attention to the underside of the cooler and the metal panels on the interior. You’ll also want to look over the cooling pads and apply an ample amount of solution to them. Most rust-removing solutions will need to sit for about 10 to 15 minutes to effectively get rid of the stains.

If you have any large stains or ones that seem to be more stubborn, take your paint scraper (or a putty knife) and gently go over them to help lift the rust from the cooler. You can also use a piece of sandpaper or a wire brush to get inside of any hard-to-reach crevices or cracks on the cooler. Be sure to scrub the cooler gently, as not to cause permanent scratch marks.

If you prefer an all-natural cleaning solution such as baking soda and vinegar, use it in a 1:3 ratio to effectively get rid of the rust. It’s easier to first pour the vinegar into a plastic water bottle and then add the baking soda instead of pouring them on the cooler individually. Let your cleaning solution sit on the cooler for anywhere from 10 to 15 minutes.

Read more information about CLR on Amazon.

4. Rinse off the cooler

After removing all the rust from the cooler, rinse it off again with your water hose to remove any debris or remaining dirt. Wipe it off with a clean cloth or sponge, and then examine it to ensure that you have gotten rid of all the stains.

Next, take a clean cloth and wipe down the cooler to dry it thoroughly before moving to the next step. It may also be helpful to let the cooler sit for about 10 to 15 minutes to air dry.

5. Repair extensive damage

If your cooler was riddled with deep stains or dents from rust, you could repair these areas using a bit of epoxy. To do this, take an epoxy mix designed for plastic surfaces and mix it– these are usually two parts solutions that need to be combined before they’re applied to a surface. Apply the epoxy to the damaged areas using a small putty knife or paintbrush. Next, let the epoxy cure for the recommended time.

6. Sand down the epoxy

After the epoxy has dried completely, sand it down using sandpaper or a sanding block. Then, wipe away any remaining debris or sand with a cleaning cloth. And you’re good to go!

Read more about this cleaning cloth set on Amazon.

How do I keep my swamp cooler from rusting?

The best way to keep your swamp cooler from rusting is to practice preventative maintenance. Let’s discuss a few tips that encompass this.

Look over the system before each use

Before turning on the cooler, inspect it ahead of time to ensure that it’s in good condition for operation. This is especially helpful if you’re using the cooler for the first time or at the start of the spring or summer seasons. Check for any debris, dirt, rust, or dead bugs around the interior or tubes. If it’s dirty, wash the cooler thoroughly and let it dry before operation.

Use quality cooling pads

The quality of the cooling pads that you use in your evaporative cooler can make a huge difference in preventing rust and other types of deposit buildup. Try to change these pads during the course of the summer. If you use the cooler daily, anywhere from one two three times should suffice. However, if you have hard water in your area, you may need to replace them up to 3 times per season.

Store it properly

Before putting away your evaporative cooler each season, always give it a thorough cleaning and ensure that it is completely dry from the inside out. This will prevent it from harboring mold, mildew, and bacteria while it’s stored. Always store it in a moderately dry location with a cover to prevent it from becoming riddled with bugs and dust.

Can I put bleach in my swamp cooler?

Close up shot of a grungy old thrashed swamp cooler as found in a junkyard in the middle of the desert, How To Remove Rust From An Evaporative Cooler

Yes. It is typically fine to add a bit of bleach to the cooler when cleaning it. However, when doing so, you’ll want to ensure that the bleach is diluted with fresh water in a bleach/water ratio of no less than 1:4. Be sure not to exceed this concentration, or you may permanently damage the cooler.

After using the bleach to clean the cooler’s interior or the tubes, always rinse out the areas with warm water afterward to completely get rid of any remaining bleach solution.

How often should I clean my evaporative cooler?

The frequency with which you clean your cooler depends on how often you use it and the conditions that it’s placed in. If you find yourself using the cooler daily during the warmer months, it’s a good idea to clean it once every one to two months. This can help prevent the accumulation of mineral deposits inside the cooler and remove any mold or bacteria that may develop.

You can typically use any all-purpose cleaning solution to do this or a combination of bleach and water to get rid of any mold.

Read more about this Lysol cleaner on Amazon.

What is the lifespan of an evaporative cooler?

On average, a decent evaporative cooler will last anywhere from 12 to 20 years, or more. Unsurprisingly, maintaining and regularly cleaning your cooler can help to extend its lifespan.

Wrapping Things Up

Removing rust stains from evaporative coolers is a fairly simple process. However, it’s best to perform preventive maintenance to prevent rust stains from occurring in the first place. This means cleaning the cooler as needed and storing it properly.

Be sure to check out some of our other posts before you go:

13 Evaporative Cooler Hacks You Should Know

14 Types Of Evaporative Cooler And Brands To Know

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