20x20x3 Air Filters

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Products   MERV Rating Filter Life Annual Cost Value Pack
Carrier PGAPXCAR2020 SpiroPure O
PGAPXCAR2020 Compatible (MERV 13)
  • $76.21
  • 1 Filters
  • ($76.21 / filters)
MERV 13
Learn more 		6 Months $152.42
Best Value!

$76.21
1 Filters

($76.21 / filter)
Carrier PGAPXCAR2020 Carrier
20x20x3 Carrier / Bryant Air Cleaner Filter PGAPXCAR2020
    5 stars
  • $125.99
  • 1 Filters
  • ($125.99 / filters)
MERV 13
Learn more 		6 Months $251.98

$125.99
1 Filters

($125.99 / filter)
MERV Rating - Contaminant Removal Guide
MERV Rating   8 11 12 13
Lint & Dust  
Dust Mite Debris  
Pollen  
Mold Spores  
Pet Dander  
Auto Emissions  
Smoke  
Tobacco  
Bacteria  
Note: equals efficient removal of contaminant by filter.

How Do I Choose the Best 20x20x3 Air Filter for My Furnace?

The 20x20x3 air filter fits HVAC systems and furnaces with a nominal 3-inch deep filter cabinet. It's less common than the standard 1-inch slot, but used in a range of residential and light commercial systems. The deeper media provides greater surface area than a 1-inch filter, which translates to better particle capture and a longer service interval. All Filters carries 20x20x3 filters in MERV 13 (actual size 20" x 20" x 2.5"). Choose your filter below or return to our full furnace filters catalog if other sizes are required for your home or office.

FAQs on 20x20x3 Air Filters

What is a 20x20x3 air filter used for?

A 20x20x3 filter fits furnaces and air handlers with a 3-inch deep filter slot. The deeper format is common in certain residential systems and some light commercial applications. It captures dust, pollen, pet dander, mold spores, and other airborne particles before they reach system components or recirculate through your home's ductwork.
MERV rating determines what particle sizes the filter captures and at what efficiency. The 3" thickness of these filters permits good air flow across the depth to allow for the more efficient MERV 13 rating that captures smaller particles for improved indoor air quality. If you previously used a lower MERV, confirm your system supports it before purchasing.
Yes. The filter slot serves the air handler, which manages airflow for both heating and cooling in a forced-air system. A nominal 20x20x3 (actual depth 2.5") filter installed in that slot works the same way regardless of whether your system is heating, cooling, or doing both.
A 20x20x3 filter typically lasts 3 to 9 months, with service life depending on household conditions and system runtime. Visually inspect 3" filters every 3 months. Households managing pets, smoke, cooking, or other activities may need to replace filters more frequently.
Turn off your HVAC system. Open the filter cabinet access panel. It's usually located where the return air duct meets the air handler. Slide out the old filter and note the airflow direction arrow printed on its frame. Insert the new filter with the arrow pointing toward the blower. Close the panel and restore power.

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