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21.5x23x1 Air Filter Merv 8
21.5x23x1 AC Filter Merv 11
21.5x23x1 Furnace Filter Merv 13
21.5x23x1 Filter Merv 13 Titanium
21.5x23x1 Filter Merv 10 Carbon
21.5x23x1 Filter Merv 8 Carbon 21.5x23x1 Filter Merv 8 Carbon
Protects All Against
  • Pollen protection
  • Dust protection
  • Mold protection
  • Dust Mites protection
    Dust Mites
  • Bacteria protection
  • Pet Dander protection
    Pet Dander
  • Smoke protection
  • Viruses protection
  • Cooking Smoke protection
  • Odor protection
  • Smog protection
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21.5x23x1 Air Filter

AC Furnace Air Filter 21.5x23x1 -Inches

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Odor Eliminator

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Product Description

Item Model Number: FKFB21.5X23A
Brand: Filter King
Filter size: 21.5x23x1
Actual Size: 21.5 x 23 x .75
1-Inch Filter
MERV 8 Filter Rating
Protection From: Pollen, Dust, Mold, Dust Mites, Bacteria, Pet Dander, Smoke, Viruses
Residential / Commercial Use

Manufactured in the US

Why Buy Air Filters From Filter King?


In comparison to fiberglass filters, 21.5x23x1 pleated air filters are at least 20 times more effective. All Filter King air filters are made in the US.


Filters frames are made out of heat resistant paperboard with horizontal grid supports. Able to withstand temperatures of up to 200° F and resistant to moisture, the paperboard frames do not support microbial growth and outperforms traditional cardboard frames.


Chemical free, electrostatically charged synthetic polyester media is pleated, maximizing the surface area, to capture a high number of airborne particles as small as 0.3 microns with low air flow resistance. To increase durability, the media is supported with a corrosion resistant steel wire.

21.5x23x1 Air Filter Reviews

What MERV Rating should I choose?

How Often to Change Your 21.5x23x1 Air Filter?

Filter King AC & furnace filters aren’t the typical fiberglass filters that need to be replaced every 30 days. Our filters can typically be used for 3 to 5 months before requiring to be changed. Naturally, a variety of things influence filter lifespan.

Some of the factors that influence your filter’s life include outdoor air quality, whether pets are in the home, and how well your HVAC system is maintained.

Your air filter becomes clogged over time by trapped particles, preventing airflow. The efficiency of the HVAC filter declines. Your system must work harder to heat and cool your home. The extra strain on the HVAC system causes higher energy bills. Regular home air filter replacements can prevent expensive system repairs or replacements down the road.

You should change your filter more frequently if you notice:

  • Household dust build-up
  • The air isn’t cooling as is used to
  • There’s more dust near the air vents
  • A dirty filter surface
  • Higher energy bills
  • Burning smells near your HVAC system.

21.5x23x1 Air Filter

Filter King 21.5x23x1 size air filters have the crucial job of keeping incoming airflow clean as it enters your home. The air filters you purchase consist of a tight mesh weaving that allows airflow through but prevents irritants from dirtying up your systems. The cleaned-out air will then cycle into your home and provide it with a fresh, clean smell. The indoor air quality of your home raises and remains high as your filters continue to clean out incoming airflow over time. The process will continue until your air filter becomes too dirty to effectively allow airflow to pass through.

Your air systems grow dirtier over time as they continue to capture particles in their tight mesh weaving. Eventually, the air filters become so dirty that airflow will have an issue going through them and into your home. When your home lacks fresh airflow, then that means that the air inside will begin to grow dry and stale over time. Your air systems will also become strained as they are forced to push airflow through the blockage. The resulting problems include mechanical damage and increased energy billing over time.

Your air filters need frequent replacement if your home is to enjoy fresh air and clean breathing consistently. Filter King is able to deliver fresh new 21.5x23x1 directly to your home. Orders of two or more filters are shipped for free, and they come frequently if you choose our subscription option. Our filters have a MERV (Minimum Efficiency Reporting Value) rating of eight, and can block out particles like:

  • Pollen
  • Dust
  • Mold
  • Dust Mites
  • Bacteria
  • Pet Dander
  • Smoke
  • Viruses

21.5x23x1 Furnace Filters

Your air filters are capable of fitting in several air systems situated around your home, including your furnace. The furnace needs air filters in order to keep the incoming heated airflow clean of any irritants. Over time, the filters become dirtier and end up blocking heated airflow from entering your home. If the air is not allowed through, then that may cause a buildup in heat that could seriously damage the system. Your home will experience temperature fluctuations since they are not being heated. Order new air filters today to keep your airflow coming in clean.