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How Do I Measure My Air Filter?

Video: How do I measure my air filter?

When needing to replace your filter, these simple steps will help you measure the right dimension. Remember, regular maintenance of your home’s cooling and heating system is essential to ensure it operates efficiently. Proper maintenance will keep good air quality in your home, increase the life span of your system, and consume less energy - lowering your bills.

Your filters should be changed every 30 to 90 days depending on the type and efficiency of your filter. However, according to Energy Star (, filters should be changed every month during peak summer and winter months when your HVAC system is operating at highest capacity.

To measure your filter, follow these easy steps:

  • Step 1: Measuring Length and Width (L x W) (If not equal lengths, the smallest measurement goes first)
  • Step 2: For safety, turn off your HVAC unit before attempting to change the filter. If you can't figure out how to turn off the unit, turn off the breaker.
  • Step 3: Most air filters are located to the right or bottom of the unit and should easily pull out of the slot. Although not common, some filters are found in air vents instead. If that is the case, you might need to contact a professional for assistance.
  • Step 4: There are arrows on the new filter to indicate which side should be facing the outside air. The filter should slide into place easily.
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