Actual size: 19.5 x 24.5 x 3.75 inches
Deep pleated air filters for whole-house and commercial HVAC systems
MERV 11 filters remove up to 95% of common particles including fine dust, smoke, and smog particles. These filters reduce allergy symptoms and protect against outdoor air pollution.
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MERV 11 air filters are designed for homes with allergies and in some cases, asthma. Those with respiratory illnesses or compromised immune systems may benefit from MERV 11 air filters due to these filters being significantly more powerful than alternative MERV filters at capturing smaller particles, such as MERV 8.
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Check the label on your current filter or use a tape measure to get the exact length, width, and depth before selecting your size.
Nominal size
Nominal size is what you normally see printed on the label. This is usually a rounded size which is often not the true size of your filter.
Actual size
Actual size is the true size of the air filter, usually written in smaller font below the nominal size.
Measure your current air filter or the length, width, and depth of the opening slot to get the actual size. Round it up to the nearest whole inch to get the nominal size.
Installing 20x25x4 air filters couldn't be easier. Just make sure to align the arrow printed on the side with the airflow direction!
Remove the air filter from the package
Locate the arrow and point it in the direction of the fan
Slide the filter in to the slot of the central unit
For return grills, insert the filter into the grill, pointing the arrow inwards
Keeping your air filter replacement schedule in mind can be challenging to say the least. Make your life easier with Filter King's auto delivery.
No, 20x25x4 MERV 13 filters are designed with deeper pleats for proper airflow. A 4-inch depth captures particles with an expanded surface area without sacrificing airflow.
Yes, your HVAC unit must accommodate 20x25x4 air filters with a proper return air rack and media cabinet. Always verify filter slot size and depth before purchasing a 20x25x4 replacement air filter.
If you notice reduced airflow, increased dust collection, and higher energy bills, it may be time for a 20x25x4 filter replacement. Most 20x25x4 air filters last between 6 and 12 months.
No, the installation of 20x25x4 filters is straightforward and typically installed in the same way as 1-inch air filters. Always check that airflow arrows (printed on the filter's frame) are facing towards the blower. Proper handling (without forcing or bending the filter) prevents damage and inefficiency.
No, folding or bending a 20x25x4 air filter can damage the pleats and frame. This can result in reduced efficiency and airflow. Using the correct size for your HVAC system is essential.
No, it is not recommended to vacuum your 20x25x4 filter when it is clogged with particles and dust. However, a light vacuuming may temporarily allow your filter to last as you await a new 20x25x4 air filter replacement.
Yes, a new 20x25x4 filter will reduce your HVAC unit's strain while simultaneously improving airflow and efficiency. The more efficient your HVAC system's air filter, the more efficient your unit will be.
MERV 8 filters