How to Winterize Your Swamp Cooler

How to Winterize Your Swamp Cooler

Drain and clean your cooling system before shutting it down for the winter

By Shelly McRae

Winterize Your Swamp Cooler: Snow on roof of house
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A swamp cooler, or evaporative cooler, works on the principle of cooling warm air with moisture and movement. During the hot summer months in desert regions, a swamp cooler draws in the dry air, pushes it through wet pads and pushes the cooled air into the building. Winterize your swamp cooler during the cooler months as part of your routine maintenance. Your cooler will operate more efficiently in the warm months and winterizing may reduce your heating costs during the winter.

  • What You Need to Know
  • Bring a tool kit (with both Phillips and flat head screwdrivers) to assist with removing the access panel.
  • Solvent cleaner and sealant are important to help keep your unit free from pests while it isn't in use.
  • To help protect your system from the elements, purchase waterproof insulation, as well as a sturdy cover or tarp.

Step 1:

Turn off the water to the cooler. The valve controlling the water flow to the cooler is likely located within in your home or on an exterior wall. Turn this valve to the off position.

Step 2:

Drain the remaining water in the swamp cooler. Remove the access panel from the unit and remove one of the pads. This gives you access to the overflow tube. Twist off the tube and allow any water in the supply line to drain into the tray. Leave the overflow tube disconnected.

Step 3:

Empty the collection tray and clean it. Use vinegar or other dissolvent to remove mineral deposits. Allow the tray to dry thoroughly and inspect it for cracks or rusting.

Step 4:

Repair cracks with a sealant such as marine sealant. If the tray has excessive cracking or rusting, replace the tray with a new one.

Step 5:

Check the supply hose above the pads. The hose has several small holes in it and is part of the water supply line. The holes allow water passing through the hose to drip down onto the pads. Use a small brush to clean any mineral deposits or debris from the holes. Check for any cracks in the hose and seal with sealant if needed.

Step 6:

Replace the pad you removed to access the overflow tube. Ensure that the pads are securely in place. You may need to replace them in the spring before turning on the swamp cooler, but to winterize the system, the pads should be in place.

Step 7:

Remove any debris from within the evaporative cooler and check that all sides and corners are properly joined. Replace any screws or bolts if necessary. Wipe down the interior of the cooler and replace the access panel.

Step 8:

Check the area around the cooler to ascertain the flashing and roof shingles are secured. Replace any loose shingles and secure loosened flashing as needed.

Step 9:

Wrap a layer of insulation around the swamp cooler. Secure the wrap so that it covers the sides of the cooler and the bottom of the insulation touches the roof.

Step 10:

Slip the cooler cover over the swamp cooler and insulating layer. The cover should fit snugly and bunch up at the bottom a little. With the insulation and cover in place, you prevent any air exchange through the system during the winter months.

  • Tips & Warnings
  • Check the interior of the swamp cooler before turning it on in the spring to ensure no debris or small animals have found their way into the cooler.
  • Make sure that power is not connected to your swamp cooler when performing maintenance. If it is connected to your house wiring, flip off the circuit breaker. If it is plugged into an outlet, make sure it is unplugged. Some units have two plugs, one for the blower and another for the pump; make sure both are unplugged.
  • Make sure that your hands are dry while working on your evaporative cooler.

About the Author

Shelly McRae is a regular contributor to DexKnows. She has experience with hydroponic gardening and other areas of the home improvement industry.

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