The Basics of Air Filter Sizes

Air Filter Sizes

Air filter sizes almost always depend on the furnace itself. While it may not be something that homeowners can easily change, it also isn’t the most important.

It is more important to use the correct air filter sizes for your specific furnace. Using the correct air filters sizes and replacing regularly is the single most important thing homeowners can do to protect their home, home air and central air system.

Why do air filter sizes matter in replacements? Using the wrong air filter sizes leads to:

· Stubborn buildup

· Poor indoor air quality

· Reduced productivity

· Low energy efficiency

· Technical repairs and damages

· High utility bills

· Unreliable heating and air conditioning

On the other hand, when homeowners use correct air filter sizes, they help protect the central air system from damages and expensive repairs. Their furnaces last longer and work well, and homeowners always have clean healthy air to breathe.

Finding Your Air Filter Sizes

Air filter sizes are very simple to find. Homeowners have three ways to locate their air filter sizes.

First, homeowners can check their existing air filters. Air filter sizes are often printed on the frames of the air filter and are shown as length by width by depth (L x W x D).

Second, homeowners can look through the furnace user manual for information on air filter sizes and types. If the manual is no longer within reach, manufacturers often have a hotline available for answers to questions.

Third, homeowners can schedule an appointment with their HVAC specialists. This is especially helpful for homeowners who are new to furnace care, have a very old furnace or have issues with indoor air quality. With a technician present to evaluate the furnace, homeowners receive accurate air filter care. Specialists also properly measure the furnace and filter chamber for the right air filter sizes.

Standard Air Filter Sizes

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There are a handful of standard air filter sizes. While air filter sizes vary in width and length, they also range in thickness from one to six inches. Some air filter sizes may come in a maximum thickness of four inches. In these cases, homeowners typically layer one four-inch air filter on top of a second two-inch air filter.

· 10 x 20

· 12 x 12

· 12 x 20

· 12 x 30

· 12 x 36

· 14 x 20

· 14 x 24

· 14 x 25

· 14 x 30

· 15 x 20

· 16 x 20

· 16 x 24

· 16 x 25

· 18 x 18

· 18 x 20

· 18 x 24

· 18 x 25

· 18 x 30

· 20 x 20

· 20 x 24

· 20 x 25

· 20 x 30

· 24 x 24

· 25 x 25

Air Filter Sizes for Improved Indoor Air Quality

The typical air filter should be replaced every 30 to 60 days.

How efficient are air filters at removing indoor air particulate? On average, no matter air filter sizes, up to 50 percent of airborne particles and pathogens are removed. However, in order for homeowners to benefit from this type of air purification, the central air system must cycle. Without the air conditioning or heating on, there is no way for indoor air to cycle through air filters.

In terms of indoor air quality, air filter sizes do matter to some degree. Thicker air filter sizes often last longer and capture more, but home conditions also factor into that decision.

Homeowners using air filter sizes with a thickness of one inch should consider an upgrade. One-inch air filter sizes typically need to be changed far more often because they fill more quickly. In addition, they may not do as good of a job in filtering particles out of air.

Thicker air filter sizes—between two and six inches—offer greater surface area and additional layers of filtration. As a result, these air filter sizes last longer and capture more particles without lowering airflow or energy efficiency.

Air Filter Sizes Versus MERV Ratings

MERV ratings should not be confused with air filter sizes. Air filter sizes are measured as length by width by depth, and calculate the actual dimensions of the air filter. MERV ratings instead measure the pore size of the air filter material.

MERV stands for minimum efficiency reported value. The higher the MERV rating the finer the pores of the air filter, no matter the air filter size.

For the average residential home, air filter sizes with a MERV rating between 8 and 12 work just fine. Air filter sizes with a MERV rating between 8 and 12 are best because they are energy efficient while retaining super filtration abilities.  

Homeowners looking to upgrade their air filter sizes with better MERV rating should also consider:

· How many people are in the home?

· What is the current condition of the home?

· What is the environment outside the home?

· Is there adequate and proper air ventilation?

· Are there animals living inside the home? How many?

· Does anyone inside the home have particular health issues?

Your unique home life factors into what air filter types you should use and at what MERV rating.

Upgrade Your Air Filter Sizes with Service Champions HVAC

All homeowners want better indoor air quality. Unfortunately, it becomes difficult to do with the wrong information and tools.

Homeowners should always consult their HVAC specialists for help, especially if you’re working with an old or unusual furnace.

Most of the time, furnaces determine what air filter sizes homeowners need. For example, if the furnace chamber only accommodates air filter sizes with a thickness or depth of one-inch, homeowners would not be able to utilize thicker air filter sizes. Unfortunately, there are many benefits that come with thicker air filter sizes. So what can homeowners do?

It is possible to have the air filter chamber resized. Heating and air conditioning contractors are able to remold and resize the chamber to accommodate larger air filter sizes. While it does require time and money, homeowners will after be able to use larger air filter sizes that deliver better energy efficiency, furnace protection and indoor air quality.

If you are interested in having your air filter chamber resized, speak to Service Champions technicians for consultation.

Trust Service Champions HVAC for the Best Air Filter Sizes

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Service Champions Heating & Air Conditioning is the Diamond Certified HVAC provider for Orange and Los Angeles Counties. Our experts lead in heating and air conditioning repairs, installations, maintenance and advanced air care solutions.

Service Champions experts know all there is to air filter care and air filter sizes. No matter what you want to do to elevate your home, we have the solutions. Thousands of homeowners trust us for our expert technical care and genuine customer service. We promise both you and your home will receive superior care.

To learn more about air filter sizes, complete the form below. You can also speak to our friendly call center representatives for further assistance.