3M Filtrete 4" Furnace Filters

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Buy 3M Filtrete 4 Inch Furnace Filters
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3M 4" Furnace Filters

The 3M 4" Media Furnace Filter provides Filtrete performance for use in whole house air cleaners installed in furnaces or central air conditioners. These filters work in any whole house system that takes a 4" filter. Filtrete furnace filters capture mold spores, pollen, dust, dust mite allergen, and pet dander. They help rid your home of these common allergy triggers and help to keep the air in your home cleaner all year round. When used under normal conditions, replace every year.

3M Media Air Cleaner filters are a universal style filter that will fit a variety of brands and models. With consist air filtration, these 4" media air cleaner filters are an excellent way to keep your home cleaner with less expense.

*Please note that the actual width may be up to 4.1875 inches.

3M 4" Furnace Filter Features

  • 1550 MPR provides exceptional performance and ensures clean indoor air for you and your family.
  • Electrostatic filtration attracts and captures particles to remove allergens from your home environment.
  • Captures 97% of airborne allergens and particles.
  • Continuously combats polluted indoor air. Filtrete furnace filters capture bacteria, viruses, smog, and smoke as well as other allergens.
  • Will not support the growth of mold or bacteria.
  • These media air cleaner filters are designed to fit a variety of air cleaner models and brands.

What Do These Furnace Filters Fit?

20x20x4 - Designed to fit Honeywell Media Air Cleaners
16x25x4 - Designed to fit Honeywell & Trion Air Bear Media Air Cleaners
20x25x4 - Designed to fit AprilAire / Space-Gard 2200 & 2250, Honeywell and Trion Air Bear Media Air Cleaners

Product Reviews

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  Black Mold
Reviewed by: Russell from West Chester, Pennsylvania

I'm very allergic to Black Mold. These 4" filters suck up and trap the nasty little spores like a sponge. Living in a Condo unit that is partially underground, humidity control and constant filtration are very important. This filter is being used 24/7 and must be changed sooner than 1 year but I won't use anything else. AchooAllergy.com has great prices and super fast shipping. I was very pleased to find the filter packaged well and damage free when it arrived.

Customer Q & A

Q1: My furnace can accomodate either a 4in. filter or a 1 in. Could I use two filters or would this harm the unit by overly restricting airflow? If I can't, which is better the 4in with a 1550 MPR or a 1 inch with a 1900? I noticed the 1inch only captured 93% while the 4inch said 97%. Being allergy free is more important than cost.

A: I'm not exactly sure since I don't know the specifics about your furnace airflow, how large is the unit, how many rooms in the home, how many floors, etc., but I would recommend going with the 4" filter. While doubling the 1" filter would improve filtration, you're still going to have more filter media with the 4" filter. The 1" filters have much tighter pleats, and I think you are right to worry that doubling this may put too much strain on the blower.

Q2: How often do these filters have to be changed? If I use a media filter, does that eliminate the need for other thinner furnace filters?

A: Typically, the 4" media filters last you 1 year, so replace annually. This may vary a bit depending on the conditions in your home and where you live. Areas effected by high levels of seasonal pollen may decrease the filter life. Generally, no, a 1" filter is not required. Most often large media filters like these are used in commercial settings where air is circulated through much larger spaces than the average home. So these thicker, larger, higher capacity filters are ideal in those situations. In commercial applications these filters are changed more frequently, but in a single dwelling, you should only need one filter per year to keep the air freer of dust, dirt, and other particles.

Q3: What is the MERV rating for your Filtrete 1550 Allergen High Performance Filter 20x25x4. Thank you

A: MERV ratings measure filtration efficiency of particles ranging from 0.3 microns and up. With more an more emphasis being placed on micro particles, 3M developed their MPR Micro Particle Rating to measure filtration of even smaller particles, down to .001. Some competitors are beginning to adopt the new standard that 3M developed but there is still predominant use of MERV. As a reference, the 3M Micro furnace filters have a MPR of 1000. Their rough equivalent MERV rating is 13-14. So while their is currently no sure equation way to convert MERV to MPR, if you use the approximate MERV rating of the Micro filter MPR rated at 1000, then the 4" filters MPR rated at 1550 would conceivably exceed MERV 18, which currently puts their filtration in line with the more expensive NordicPure furnace filters. Because 3M uses this different measuring scale and system, it's difficult to do a straight comparison.

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Additional Resources

Furnace Filter Buying Guide
Learn more about how to control mold.
Read more about how to control dust mites.

Filtrete 4" Furnace Filter Availability

20 x 20 x 4 (Item#: 3M0073) $29.95
20 x 25 x 4 (Item#: 3M0074) (Out of Stock)

Could not wait to try Safeguard Window Filters. I am using them, am very pleased and have high hopes that my solution to open windows is at hand!
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