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Is it time to shut down those evaporative coolers yet? If it’s already October, and the weather is starting to cool down, it just might be. If you follow these basic steps for preventative maintenance each fall, then you will thank yourself by May when 100-degree temperatures return.

Using nature’s principle for cooling, evaps cool space through the evaporation of water. The unit draws hot air through wet pads which cools the air and then blows the air into the home creating constant air movement in the home making people feel even cooler.

The unit houses evaporative pads, a blower and blower motor to circulate the air, water lines, a float to regulate the water level, and a water recirculating pump to help conserve water. Better pumps will have bleed off valves to reduce mineral build up.

If you use only evap cooling in your home, then here are some tips to make sure you derive maximum efficiency from your unit during the time of year when it must work the hardest.

  1. Make sure that the water lines are distributing water evenly. Look carefully at the cooling medium (pads) and make sure there are no dry spots. Dry spots indicate poor water distribution. Make sure that the pads have not settled leaving a gap at the top edge that allows hot air to flow into the unit.
  2. Clean the water reservoir beneath the cooler. This pan holds the water that is recirculated through the pads. Whatever is in that pan (mud, grime, grease) is circulating through the water lines and into the pads.
  3. Scrape away loose paint and use a wire brush to wipe away rust. Next, prime and repaint using Rust-Oleum primer and Submarine Cooler Coating on the inside of the unit. Do not apply paints below the water line. If your water reservoir has already been painted, then it’s ok to touch it up and repair as needed. Otherwise, leave the pan unpainted.
  4. Make sure the blower belt is tight, but not so tight that it strains the electric motor. The belt should move about 3/4–1 ½” at mid span (depending on the size of the unit) when you tug on it.
  5. Oil the bearings and tighten the pulley set screws
  6. Install a new anode kit to prevent rust and deterioration and purchase a scale eliminator product that comes in a bag to put in the water when you start your cooler back up in the spring.
  7. At the end of the season, remove the cooler pads from the metal cabinets, wrap them in garbage bags and then reinstall the pads into the panels. This will help seal-up your metal cooler for the winter months. Next spring when the heat approaches, all you will have to do is uncover your cooler, install a new set of Fatpad pads, turn on the water, and adjust the float.

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