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Maintain a Healthy and Clean Air in Your Home with the Best Furnace Filter

It’s time to change the air filter in your home, but which is the best furnace filter out there? With an abundance of available options, it can be overwhelming to know which one will meet your needs.

 Best Furnace Filter

That’s why we’ve put together this article to investigate five different air filters, their features, what their ratings mean, and our top three picks. So, keep on reading to learn what you should know before purchasing your air filter replacement.

Top 3 Picks for Best Furnace Filter Replacements

Best Overall – Filtrete Micro Allergen Defense Air Filter

Designed specifically to remove allergens from the air, these MERV 11 rated filters provide superior filtration from pollen, pet dander, smoke, and other airborne allergens while maintaining your furnace or air conditioner’s performance. With the added feature of a Smart App that sends you reminders when it’s time to change your filter, we vote this filter the best overall on our list.

Best Quality – Filtrete Clean Living Basic Dust Air Filter

Designed for use in residential air conditioners and furnaces, these filters boast a MERV 5 rating and 3-in-1 technology that removes dust, mold spores, and other pollutants from the air. The electrostatically charged material attracts and traps the particles ensuring they don’t migrate through the filtered air. With superior construction and an added Smart App feature to remind you when it’s time to change your filter, the Filtrete brand gets our vote for best quality.

Best Bargain – The AIRx Allergy Air Filter

Designed for residential air conditioning units and furnaces, these filters boast a MERV 11 rating that is ideal for trapping most airborne particles and allergens while maintaining the performance of your heating and cooling systems. With superior construction and a full ninety-day life span, the AIRx filters are the best bargain on our list.

What is a HEPA Furnace Filter?

HEPA (High-Efficiency Particulate Air) filters are superior quality air filters that remove more than 99% of particles larger than 0.3 microns from the air, including many bacteria and viruses. These filters are typically used in hospitals and other applications where high air quality is of utmost importance.

Due to the dense material used in HEPA filters, they are not recommended for residential use as the air pressure required to push air through them is typically more than a residential furnace or air conditioner can handle. Airflow would be restricted to a point where little to no air would reach the vents and potential damage could be caused to the furnace or air conditioning unit.

For residential use, air filters with higher-level MERV ratings come fairly close to HEPA levels with the exception of removing viruses from the air. Although a MERV rating of 13 or more is closest to the filtration of a HEPA filter, MERV ratings between 7 and 13 are just as effective and anything over a MERV 11 is considered overkill for most residential applications.

If for health reasons, your home requires the filtration levels that a HEPA filter offers, or you simply want that level of air quality, it is recommended that you install a separate air filter system that can handle the HEPA’s demands. This will give you the air quality you desire without affecting the performance of your furnace or air conditioning unit.

How Often Do You Change a Furnace Filter

How Often Do You Change a Furnace Filter?

In general, a furnace filter should be changed every ninety days but there are a few factors to think about that may make you want to change them more often.

Many manufacturers state on their packaging when the filter should be replaced and most of these are based on their MERV rating. Typically, filters with MERV ratings of six to nine should be replaced every ninety days, while filters with MERV ratings over nine should be replaced every sixty days. To simplify a filter replacement schedule, many manufacturers recommend that you replace your filter at the start of each season which works out to every ninety days give or take a few.

Lifestyle, health, and climate are also big factors in deciding how often to replace your air filter. If you have pets or live in dusty climates, changing your air filter every month may be a good idea. People with allergies, asthma or other respiratory illnesses may want to change their air filters every thirty to sixty days to help keep the air in their home at its cleanest. If you live in colder climates where your furnace is running constantly for months, replacing your filter every sixty days could prolong the life of your furnace.

When to replace your air filter is largely a personal preference, but if you keep to the minimum suggestions of every ninety days or at the start of each season, you can be confident that the air you’re breathing is filtered and clean.

Furnace Filter Sizes

Furnace Filter Sizes

There are various furnace filter sizes available, and all come in various thicknesses. To determine the filter you require, record the size listed on your current filter and measure the cavity the filter sits in. It is important that your filter fit properly to ensure you are getting the best air quality available. We have listed a couple of furnace filter sizes here to give you an idea of how each works in terms of size and efficiency.

  • 16x20x4 furnace filter
    • Allows for 665 cfm of return airflow.
    • Captures a higher percentage of airborne particles than a one-inch-thick filter.
    • Allows for better airflow than a thinner filter with the same MERV rating can provide.
  • 16x20x5 furnace filter
    • Allows for 665 cfm of return airflow.
    • Capturers and an even higher percentage of airborne particles than its four-inch counterpart.
    • Allows for even better airflow than its four-inch counterpart.
  • 20x25x4 furnace filter
    • Allows for 1040 cfm of return airflow.
    • Captures a higher percentage of airborne particles than a one-inch-thick filter.
    • Allows for better airflow than a thinner filter with the same MERV rating can provide.
  • 20x25x5 furnace filter
    • Allows for 1040 cfm of return airflow.
    • Capturers and an even higher percentage of airborne particles than its four-inch counterpart.
    • Allows for even better airflow than its four-inch counterpart.

The Best Furnace Filters for Your HVAC System

AC Furnace Air Filter

AC Furnace Air Filter

The Filtrete Micro Allergen Defense Air Filters for your furnace, air conditioner, and other HVAC systems offer a unique 3-in-1 technology that is specifically designed to remove allergens from the air. The electrostatically charged material captures fine particles like pollen, pet dander, lint, dust, and smoke and the MERV 11 rating means you’re breathing high-quality filtered air every day.

Their pleated and washable design outperforms fiberglass filters and lasts for three months before needing to be washed or replaced. For residential use, the Filtrete Smart App allows you to set a reminder that will send you notifications when it’s time to change the filter.

Pros

  • Available in three different sizes.
  • Available in two and four packs.
Cons

  • Requires a large compartment depth (4 to 5 inches).

FilterBuy Air Filter MERV 8

FilterBuy Air Filter MERV 8

The FilterBuy Pleated Air Filter for HVAC, air conditioning, and furnace use is made of electrostatically charged synthetic material that attracts and captures 90% of airborne particles in your home. With a MERV 8 rating and pleated design, it is an ideal filter for homes with pets and other potential allergens.

Manufactured with recyclable material, industrial-grade beverage board, and dual-wire backing, the FilterBuy filters outlast and outperform fiberglass filters and other cardboard designs. They are ideal for standard residential and commercial use and last for up to ninety days.

Pros

  • Available in multiple sizes.
  • Reduce pet dander and fur in the air.

Con

  • Some discrepancy in the actual thickness of the filter online.

Filtrete AC Furnace Air Filter

Filtrete AC Furnace Air Filter

The Filtrete Clean Living Basic Dust Air Filter for your furnace and air conditioner units offers Filtrete’s unique 3-in-1 technology that is specifically designed to remove large particles, dust, dust mite debris, and mold spores from the air. The electrostatically charged material captures fine particles and the MERV 5 rating creates a clean and healthy home environment.

Its pleated and washable design outperforms fiberglass filters and lasts for three months before needing to be washed or replaced. For residential use, the Filtrete Smart App allows you to set a reminder that will send you notifications when it’s time to change the filter.

Pros

  • Available in packages of six.
  • Limited warranty.

Cons

  • Not UV resistant.

AIRx Filters Allergy

AIRx Filters Allergy

The AIRx Allergy Air Filter for air conditioning units and furnaces is made of electrostatically charged synthetic material that traps airborne particles like pollen, lint, dust, mold, pet dander, and smoke while maintaining the efficiency of your AC and furnace units. With a MERV 11 rating, you can be sure you’re breathing clean air for the life of your filter.

Made in the US from moisture-resistant, double-walled beverage cardboard and boasting more pleats per inch than leading brands, AIRx Allergy Filters exceed industry standards for efficiency and last a full ninety days before replacement.

Pros

  • 1-year manufacturer’s warranty.
  • Available in multiple sizes.

Cons

  • Cannot be recycled.

Trion Air Bear MERV 11

Trion Air Bear MERV 11

The Trion Air Bear 259112-102 Air Filter is manufactured with electrostatically charged synthetic material that attracts and captures pollen, pet dander, dust, dirt, and other particles in the air. The filter’s MERV 11 rating means you get superior filtration and cleaner indoor air.

These 5-inch-thick filters boast extended surface pleats that hold more dirt than leading brands and last for up to six months before changing.

Pros

  • High efficiency.
  • Longer life span.

Cons

  • Not UV resistant.
  • No mentioned warranty.

How Do You Change a Furnace Filter?

Changing an air filter is typically quick and easy and requires little to no tools to complete. The owner’s manual for your furnace or air conditioning unit should have instructions on how to replace the filter, but in general, it can be done in a few easy steps.

Make sure to turn off the unit before proceeding to any other step. Once the unit is safely turned off, remove the face of the service panel. This can often be done by removing a few screws in the corners of the panel. Find the filter located near the intake/outtake fan and remove the old filter. Slide the new filter back into the same location. The filter should have arrows or some other markings indicating which side should face out. Once the new filter is in place, replace the face of the service panel and turn the unit back on. Your new filter is now installed. Discard the old filter per the manufacturer’s instructions.

What is a Furnace Filter MERV Rating?

A furnace MERV (Minimum Efficiency Reporting Value) rating is a measurement on a scale of one to sixteen that indicates how effective the filter is at trapping small particles such as dust, dander, pollen, mold, and other airborne irritants. The higher the MERV rating, the more efficient the filter is.

A filter’s MERV rating indicates the lowest possible performance you can expect from that filter. Meaning that is the minimum amount of particles that the filter can handle, but it will likely handle more. The recommended MERV ratings for residential use are between seven and thirteen. Filters with a MERV rating of higher than thirteen as well as HEPA filters are typically used only in hospitals and other healthcare environments where air sanitation is required.

Filters with a MERV six to eight rating are the most inexpensive options but are also considered the minimum of efficiency standards. They are great for catching large airborne particles but not as good for small ones.

MERV nine and ten rated filters are the most commonly used filters in residential applications and are also relatively inexpensive. These filters are great for catching large particles as well as a lot of smaller particles such as pollen and mildew spores. They are the minimum rating allergy sufferers would want to use in their homes.

Filters with MERV eleven and twelve ratings are highly efficient at catching most large and small airborne particles and are ideal for people with pets, allergies, asthma, and other respiratory illnesses. They are slightly more expensive than lower MERV-rated filters but offer the best residential air filtration.

MERV thirteen-rated filters are the best at removing most airborne particles including bacteria, smoke, and some viruses. They are ideal for people with severe asthma and respiratory illness as well as people who are prone to various illnesses. It is important to note however that these filters come with a heftier price tag and are not recommended for standard household use.

Filters with a MERV fourteen or higher rating are not recommended for residential use and can actually harm residential furnaces and air conditioning units. Due to the thick filtration material used on these filters they can also greatly restrict airflow in residential units that are not designed for that much air pressure. These filters are typically quite large and are specifically designed for hospitals and other medical facilities that require sanitized air filtration.

Conclusion

In summary, before purchasing your new air filter be sure to measure or record the actual size of your current filter to ensure a proper fit. Also, consider your lifestyle and where you live to determine the MERV rating that will suit your needs the best. With a plethora of available options, you’re sure to find the right filter for your home in no time at all.

Thanks for reading! We hope you found this article helpful. Drop us a comment or question about this topic, we would love to hear from you.