Best 20x20x1 Air Filter

Air filters come in various sizes. In this review, we shall focus on 20x20x1 furnace filters. This type of furnace filter is unique because of its thickness.

The 1-inch furnace filter is the smallest in a broad range of filters that can be as thick as 5 inches. In this review, we shall look at some of the best 20x20x1 furnace filters you can use in your HVAC.

We will also show you how to measure the size of your furnace filter.

How to Size a Furnace Filter

Sizing your furnace filter is important because it will not fit into your system if you get the wrong size. If you have a large furnace filter, it will not fit into space in your HVAC system. Moreover, cutting your furnace so that it can fit into your system is not a good idea.

If you have a large furnace, it will fit loosely in the space designed for the air filter. This means that the filter will not serve you as you would expect. A poorly fitting filter will let all manner of particles through. This will compromise your Indoor Air Quality.

You can size your funnel filter by measuring the length, width, and thickness. The length, width, and thickness figures of furnace filters are usually expressed in inches. Therefore, the size of a furnace filter may be expressed this way: 20x20x1. This means that the furnace filter is 20 inches long, 20 inches wide, and one inch thick.

This is what is referred to as the nominal size. It is expressed in whole numbers. The actual size of the filter is usually less by 0.5 inches. Therefore, the actual size of the filter above maybe 19.5 x 19.5 by 0.5.

What is a 20x20x1 Furnace Filter?

A 20x20x1 furnace filter is the thinnest air filter that you will find on the market. However, it is not the smallest in terms of length and width. Many other furnace filters measure as low as 16 or 14 inches in either length or width.

A typical 20x20x1 furnace filter may measure 19.5×19.5×0.5. this is the actual size of such an air filter. The biggest feature that defines this kind of furnace filter is its thickness. Being the thinnest furnace filter available, this furnace filter is the best in allowing the free flow of air in the house.

The thickness of furnace filters determines the length of time it takes to be full of contaminants. A furnace filter that is 5 inches thick will last longer than one that is 2 inches thick.

Therefore, although your 1-inch-thick furnace filter will guarantee you a comfortable environment because it will trap contaminants without interfering with airflow around the house, it will not last for a long time. You will be forced to replace it sooner than later.

Differences Between a 20x20x1 and 20x25x5 Furnace Filter

The difference between a 20x20x1 and a 20x25x5 furnace filter is in size. A 20x25x5 furnace filter is broader and thicker than a 20x20x1 furnace filter. A 20x20x1 furnace filter is square-shaped, while a 20x25x5 furnace filter is rectangular.

The difference in the thickness between these two types of furnace filters becomes apparent when you start using them. Your 1-inch furnace filter will become full of contaminants faster than your 5-inch one. This is because the 5-inch one is thicker and has a larger surface area for accommodating contaminants than the 1-inch one.

There is no relationship between the thickness of a furnace filter and the MERV rating. Therefore, you may find a thicker air filter with a relatively low MERV rating of about 8. It is also possible to get a thin furnace filter with a very high MERV rating of over 14.

Is a 2-Inch Filter Better than a 1 Inch?

The rule of thumb is that a 2-inch filter is better than a 1-inch filter. A 2-inch filter will last longer than a 1-inch filter. This is because of its more significant surface area because of being thicker than a 1-inch filter.

Moreover, a 2-inch filter is suitable for your HVAC system than a 1-inch filter. You will not have to regularly replace your 2-inch filter as would be when you have a 1-inch filter.

However, in practice, you need to understand the kind of filter that your HVAC system is compatible with. It would be improper to use a filter that is of the wrong size.

Because of this, let a certified HVAC professional help you to choose the right size of filter for your HVAC system. If you have the wrong size, the system’s blower may strain to keep the air moving around the house freely. This may increase the chances of some components of the system getting damaged. Repairing a damaged HVAC system is often a time-consuming and expensive process.

Benefits of a 20x20x1 Furnace Filter

Improving the Indoor Air Quality

A 20x20x1 air filter, like any other type of air filter, presents you with various benefits. Primarily, using the air filter helps to improve your Indoor Air Quality. The Indoor Air Quality is measured by the percentage of contaminants that are found in your home.

The higher the percentage of contaminants, the lower your Indoor Air Quality. Therefore, if your furnace filter effectively removes a considerable percentage of the contaminants, it will improve your Indoor Air Quality.

Preventing Allergies

Your 20x20x1 furnace filter can play a critical role in fighting allergies in your home. Allergic reactions are caused by the presence of allergens in the air. The allergens may be in the form of small fur particles from your pets, dust, smoke, or even mites.

Your filter can effectively trap all these types of allergens. This will keep the air in your house free from allergens and protect everyone who has an allergy.

How to Replace Your 20X20X1 Furnace Filter

Replacing your 20x20x1 furnace filter is a straightforward process. Here are the steps that you need to follow to complete the simple procedure within no time.

  1. Open the filter compartment. You can do this with the help of any sturdy and straightforward tool or by hand. It all depends on the design of your HVAC system.
  2. Remove the old filter that needs to be replaced. The old filter will be full of dust and other contaminants. Its color would have changed to dark grey or black.
  3. Fit the new filter into space. Use the arrows indicated on the side of your new filter to fix it into the compartment. Ensure that the filter frame has fitted perfectly into space so that there are no extra spaces around it.
  4. Close the compartment. Close your filter compartment properly. Once you are done with this step, you will be free to continue using your new filter until you feel that you need to replace it.

What Happens if you put the Furnace Filter Backward?

If you place your furnace filter backward, the fibers will not do their work of attracting and catching contaminants properly. This means that the air in your house will be full of all manner of contaminants, including dust, mite, and smoke.

Furthermore, placing your air filter backward increases the risk of damage to your HVAC system. The blower and other system components will be forced to overwork to try to maintain a comfortable indoor environment for you. However, this comes at the cost of regular and costly repairs of the components of the system.

Best 20x20x1 Air Filter – Reviews

1. Aerostar Clean House 20x20x1 Air Filter

Aerostar 20x20x1 MERV 8 Pleated Air Filter, AC...
  • Nominal size: 20x20x1; Actual size 19 3/4"x 19 3/4" x 3/4"; This MERV 8 filter is comparable with MPR 600 & FPR 5.
  • Designed to filter microscopic particles such as lint, dust mites, spores, and pollen
  • Simple to install and a cost-effective step towards a healthier home environment. For best results, change your filters every 60 to 90 days but increase frequency to 30 days during peak summer and winter months
  • 100% synthetic electrostatic media for high efficiency with low air flow resistance
  • Manufactured in the USA by Filtration Group, a world-leading manufacturer and supplier of filtration solutions making the world safer, healthier & more productive

The Aerostar Clean House 20x20x1 Air Filter is one of the best air filters you can use in your HVAC system at home or in commercial buildings.

The filter is made o 100% synthetic material with very little resistance to airflow. Thus, you do not have to worry about the filter interfering with the free flow of air in your house.

The surface of the Aerostar Clean House 20x20x1 Air Filter is pleated. Furnace filters with pleated strands are more effective than those without pleated strands.

The pleating increases the surface area, which maximizes the percentage of contaminants that are successfully trapped by the air filter.

This furnace filter is ideal for fighting odors and allergies. Its surface is electrostatically charged. This means that the air filter can automatically attract and trap microparticles that cause odors as well as allergens that may be floating around the air in your home.

Pros:

  • Perfect for fighting allergies and odors because it has an electrostatically charged surface
  • Its pleated surface enhances filtration performance
  • It is made from 100% synthetic material with low airflow resistance

Cons:

  • It has a relatively low MERV rating of 8

2. Crisp Filters, 20x20x1 Air Filter

Crisp Filters, 20x20x1 Air Filter, MERV 8, MPR...
  • ENHANCED AIR FILTRATION: Our 20x20x1 air filters are made using an advanced pleated technology that offers more air coverage, better particle capture performance and helps extends the life of your furnace, air conditioner, or HVAC system.
  • KEEP YOUR INDOOR AIR CLEAN: MERV 8 20x20x1 furnace filters are the ideal choice for anyone wanting clean, crisp air in their home. Our air filters trap dust, debris, pollen, and dust to help improve air quality. Actual Size is: 19 ¾ x 19 ¾ x ¾
  • LONG-LASTING PERFORMANCE: Thanks to the thick build and pleated design, our air conditioner filter offers better capture coverage to trap more unwanted air particles and provides resilient filtration for up to 3 months to let only clean air pass through
  • EASY & SIMPLE TO USE: Installing or replacing our air filters for AC units or furnace is as simple as it gets. Simply slide the filter into the air filter return of your unit and you’re done! It’s recommended to change your filters every 90 days to maintain optimal filtration
  • QUALITY THAT COUNTS: We designed our pleated air filters with more pleats than most retail air filters to enhance airflow and efficiency. Each filter is made in the U.S.A with close attention to even the smallest details making it ideal for any residential home

One of the most exciting features of the Crisp Filters, 20x20x1 Air Filter, is how it traps all manner of contaminants. This filter is made to trap particles that are as small as 0.3 microns in diameter and large ones that measure 1.0 microns. Thus, the air filter will adequately protect you from mites, dust, smoke, allergens, and even microorganisms that cause cold and flu.

Moreover, this furnace filter provides enhanced filtration performance because of the use of a unique pleating technology. The pleated strands on this furnace filter increase the surface area. This ensures that eth filter traps as many types of contaminants as possible.

The only notable drawback of using this furnace filter is that it has a relatively low MERV rating of 8. There are many other brands of 20x20x1 air filters with high MERV ratings of even 14.

Therefore, if you are keen on getting a furnace filter with an exceptionally high MERV rating, you will have to look for an alternative.

Pros:

  • Advanced filtration capacity because of the use of a new pleating technology
  • The filters are designed to trap all types of contaminants, including smoke, dust, and allergens.
  • Easy installation and use

Cons:

  • The MERV rating of 8 is relatively low

3. Filtrete 20x20x1, AC Furnace Air Filter

Filtrete 20x20x1, AC Furnace Air Filter, MPR 300,...
  • Outperforms fiberglass, washable and non electrostatic 3 month pleated 1 inches air filters for your furnace, air conditioner, or HVAC system
  • Exclusive Filtrate Brand 3 in 1 technology from 3M traps unwanted air particles, while letting cleaner air flow through
  • Attracts and captures large particles such as lint, household dust, dust mite debris and mold spores
  • Filtrate 300 MPR (Micro particle Performance Rating) equates to MERV 5
  • For optimum performance, change your home air filter every 90 days or sooner
  • For residential use only
  • The higher the MPR, the more micro particles; such as pollen, pet dander, smoke, bacteria and viruses, your filter will capture from the air passing through it
  • A dirty filter will slow down air flow and make the system work harder to keep you warm or cool wasting energy; Sign up for a filter change reminder program that works for you
  • Packaging and filter media may vary for MPR 300

The Filtrete 20x20x1 AC Furnace Air Filter is perfect for keeping your Indoor Air Quality high. This furnace filter effectively captures all the large contaminants, including dust, smoke, and lint.

This means that you will feel comfortable staying indoors because this filter will keep such contaminants away from your indoor environment.

Besides, the furnace filter comes in a pack of 6 pieces. This helps to save the time that you would otherwise have to use to get new packs often. One piece can last for as long as 90 days. This is of great convenience because you will not have to check and replace your furnace filter regularly.

However, the Filtrete 20x20x1 AC Furnace Air Filter has a MERV rating of 5. This MERV value is relatively low, considering that there are many other brands of similar air filters with high ratings of even 14. Nevertheless, the furnace filter does an excellent job in trapping large contaminants.

Pros:

  • It lasts for up to 90 days before needing replacement
  • There are six pieces in every pack, which gives you value for your investment
  • It effectively attracts and captures large particles, including dust

Cons:

  • It has a low MERV rating of 5

4. Aerostar Home Max 20x20x1 Air Filter

Aerostar 20x20x1 MERV 13 Pleated Air Filter, AC...
  • Nominal size: 20x20x1; Actual size 19 3/4"x 19 3/4" x 3/4"; This MERV 13 filter is comparable with MPR 1500-1900 & FPR 10.
  • Designed to filter microscopic particles such as lint, dust mites, spores, pollen, pet dander, fine dust, smoke, viruses, and bacteria
  • Simple to install and a cost-effective step towards a healthier home environment. For best results, change your filters every 60 to 90 days but increase frequency to 30 days during peak summer and winter months
  • 100% synthetic electrostatic media for high efficiency with low air flow resistance
  • Manufactured in the USA by Filtration Group, a world-leading manufacturer and supplier of filtration solutions making the world safer, healthier & more productive

One of the most notable features of the Aerostar Home Max 20x20x1 Air Filter is its high MERV rating. With a MERV rating of 13, this furnace filter can successfully pick up a large percentage of contaminants that may be found in your home. It can capture up to 92% of all the contaminants in your home, thus leaving you with a high-quality indoor environment.

Another exciting feature is that the furnace filter comes in a pack that contains six pieces. This saves you the trouble of having to purchase a new pack of furnace filters quite often.

The only significant issue about this air filter is that it does not last for as long as you would expect it to do.  Although the manufacturer has indicated that the air filter may last up to 90 days, in practice, this is hardly the case. You may have to replace your filter within a shorter time than this.

Pros:

  • High MERV rating of 13 for superior filtration performance
  • It has a pleated surface for a maximum surface area
  • There are six pieces in every pack

Cons:

  • The air filter does not last for a long time

5. Filtrete 20x20x1, AC Furnace Air Filter

FilterBuy 20x20x1 Air Filter MERV 13, Pleated HVAC...
  • 20x20x1 replacement air filters for your furnace, air conditioner, or HVAC system (actual size: 19.50 x 19.50 x 0.75 inches)
  • MERV 13 synthetic media (comparable with MPR 1500-1900 & FPR 10) protects homes optimally by trapping 98% of airborne particles without impacting air flow
  • High-quality construction features an electrostatically charged, pleated design that captures more harmful particles and prolongs the products lifespan by 3 times that of fiberglass models
  • Industrial-grade beverage board frames with dual wire backings outperform standard cardboard designs
  • All components are manufactured within the United States and designed with recyclable materials

The Filtrete 20x20x1 AC Furnace Air Filter is designed to fight odors and allergies. It has an electrostatically charged surface that perfectly attracts and traps contaminants of all types, including allergens and microorganisms.

The microorganisms are usually contained in cough and sneeze droplets. Therefore, this air filter will protect you from the spread of cough, cold, and flu.

This furnace filter can also help to keep your home free of odors. Its surface is powerful enough to capture the microparticles that cause odors at home. Thus, installing this furnace filter will dramatically increase your Indoor Air Quality.

The Filtrete 20x20x1 AC Furnace Air Filter has pleated strands. The pleating of the strands increases the surface area of the filter. Contaminants that are not trapped when they first fall on the surface are eventually caught as they attempt to make their way through the filter mesh.

However, this filter does not last for a long time. It may be necessary to replace it earlier than after three months, as suggested on the packaging. The good news is that every pack contains four pieces.

Pros:

  • High MERV rating of 11
  • It has an electrostatically charged surface for trapping contaminants
  • The strands are pleated to increase the surface area

Cons:

  • The furnace filter lasts for a short time

6. Aerostar Clean House 20x20x1 Air Filter

Aerostar 20x20x1 MERV 11 Pleated Air Filter, AC...
  • Nominal size: 20x20x1; Actual size 19 3/4"x 19 3/4" x 3/4"; This MERV 11 filter is comparable with MPR 1000-1200 & FPR 7.
  • Designed to filter microscopic particles such as lint, dust mites, spores, pollen, pet dander, fine dust, and smoke
  • Simple to install and a cost-effective step towards a healthier home environment. For best results, change your filters every 60 to 90 days but increase frequency to 30 days during peak summer and winter months
  • 100% synthetic electrostatic media for high efficiency with low air flow resistance
  • Manufactured in the USA by Filtration Group, a world-leading manufacturer and supplier of filtration solutions making the world safer, healthier & more productive

If you are looking for a primary furnace filter to keep your Indoor Air Quality high enough and remove all common contaminants, consider using the Aerostar Clean House 20x20x1 Air Filter.

This furnace filter is built to trap all elemental contaminants, including dust, mite, and fur particles from your pets. Therefore, it can protect you from allergies.

The Aerostar Clean House 20x20x1 Air Filter is made of 100% synthetic media. Furthermore, the media is charged to enhance its air filtration performance.

The frames of this furnace filter are made from high-quality materials. This means that the furnace filter can withstand the effects of the elements, including heat and moisture.

Besides, the furnace filter hardly interferes with the flow of air in your house. Thus, you do not need to worry about your blower overworking when you install this furnace filter.

However, because of the MERV rating of 8, this furnace filter will not remove 97% of the contaminants that may be present in your house.

Pros:

  • 100% synthetic material with very minimal interruption of airflow
  • The media is electrostatically charged for maximum air filtration performance
  • It lasts for even 90 days

Cons:

  • It has a low MERV rating of 8

Conclusion

20x20x1 furnace filters are ideal for creating a comfortable indoor environment at home or a commercial premise. Depending on whether the fibers of the filters are pleated, they can effectively capture massive amounts of all types of contaminants.

The filters trap contaminants that are as small as 0.3 microns wide and as large as 1 micron wide. The higher the MERV rating, the more significant the percentage of contaminants that a 20x20x1 furnace filter can trap.