How to Replace Mastercool Pads

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Things You'll Need

  • Hammer (optional)

  • Screwdriver (optional)

This is the frame in which Mastercool pads are situated.

Mastercool pads refer to the products that Mastercool evaporative coolers use to evaporate water, cooling homes in hot, dry locations. Evaporative coolers use far less electricity than conventional air conditioners and can cool the air as much as 30 degrees in places like southwestern California's deserts, Arizona, New Mexico and parts of Colorado. 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 cleaning or replacing periodically because the salts in the water collect on the pads, impeding water saturation and air flowing through the pads.

Step 1

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.

Step 2

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 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

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 at the top to help distribute the water evenly to all the cells inside the pads.

Step 5

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 6

Replace the metal rods or the holding clips and reinstall the frames. Plug the 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.


If your pads hold a lot of mineral deposits, put down 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 are finished with the old pads, dump the accumulated salts into a garbage can.


Jackie Johnson

Jackie Johnson is a published writer and professional blogger, and has a degree in English from Arizona State University. Her background in real estate analysis prepared her for objective thinking, researching and writing.