How to Replace Mastercool Pads

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Changing your Mastercool pad is an important part of evaporative cooler maintenance that keeps the system running. Evaporative coolers use far less electricity than conventional air conditioners and can cool the air as much as 30 degrees in low-humidity areas. Evaporative coolers or swamp coolers pull air through the wet pads, causing the water to evaporate and effectively cool the air. Mastercool pads are thick, absorbent pads that need to be cleaned or replaced to keep water and airflow sufficient.


Step 1: Turn Off the Power

Shut off the evaporative cooler and unplug it. Swamp coolers have moving motors, fans, and belts that can cause injuries to anyone working on a cooler.

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Step 2: Remove the Frame

Remove the frame or frames that hold the pads. You may need to manually loosen the frames if mineral water salts have formed a crust between the pad's frame and the evaporative cooler. The top of the frame has a gutter inside it to capture the water that flows from the spiders located inside the top of the cooler.


Step 3: Remove the Retaining Rods

Remove the retaining rods or clips and pull out the old pads. Mastercool pads fit tightly inside the frames and you may need to use a screwdriver to loosen the pads away from the frames.

Step 4: Remove the Old Pads

Pull the old pads out of the frame. If your pads hold a lot of mineral deposits, put down a tarp or old sheet to capture the salts that fall out of the pads while you remove them. Salts damage concrete and soil. When you're finished with the old pads, dump the accumulated salts into a garbage can.


Step 5: Inspect the Old Pads

Look over the old pads to see if they need to be replaced. If your system uses Aspen pads, they should be replaced at the beginning of the season and sometimes once or more during the season. If you're using a Mastercool rigid media pad, you can sometimes clean and reuse it. Throw it away if it shows damage or has mold, mineral buildup, or other issues. If it's still good, you can spray it with a garden hose and reuse it.


Step 6: Prepare the New Pads

Take the new pads out of the boxes, making sure that you note the top from the bottom. The tops of Mastercool pads have a strip of felt to help distribute the water evenly to all the cells inside the pads.

Step 7: Put New Pads in Frames

Install the new pads in the frames. The pads fit snuggly in the frames and you may need to use some pressure to nest the pads inside the frames. When forcing the new pads in the frames, be careful that you do not damage the cardboard cells, which could diminish the cooling capacity of the evaporative cooler by compressing the cells.


Step 8: Replace Rods or Clips

Replace the metal rods or the holding clips and reinstall the frames. Plug the evaporative cooler back in and turn on the water pump to moisten the pads. When the pads are thoroughly wet, turn the fan back on to resume cooling the home or building.



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