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6FM2020 20" x 20" x 5" MERV 11 Filter Media
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$48.43 each
In Stock
Get 5 Tue, Jul 7
Order by today, receive Tuesday
This item replaces: 4531
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Product Highlights
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Synthetic
20" x 20" x 5"
11 MERV Rating
Description
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General Aire 6FM2020 20" x 20" x 5" MERV 11 Filter Media (4556)
A replacement HVAC media air filter used in a compatible General Aire filter cabinet to remove airborne particulates from the return-air stream.
Key Features:
Compatibility & Applications:
Installation & Operation Notes:
Maintenance & Troubleshooting:
User Reviews & Q&A Summary:
A replacement HVAC media air filter used in a compatible General Aire filter cabinet to remove airborne particulates from the return-air stream.
Key Features:
- MERV 11
- Size: 20" x 20" x 5"
- Material: Synthetic
- Listed for MAC 2020
- Listed as replacing: 4531
Compatibility & Applications:
- Listed for MAC 2020.
- Must only be used where the manufacturer specifies this exact filter/media designation and/or part number: 6FM2020 / 4556.
Installation & Operation Notes:
- Installation can typically be performed by a homeowner or HVAC technician, but you should follow the air cleaner/furnace documentation for the correct access method and airflow orientation (no installation steps are provided in the provided sources).
- Confirm fit before forcing the filter into the cabinet - multiple reviews emphasize that "20 x 20 x 5" can vary in actual dimensions depending on the system and the filter.
Maintenance & Troubleshooting:
- This is a routine maintenance filter. Common replacement triggers mentioned in reviews include:
- Filter loading faster in high-occupancy/pet homes.
- Reduced airflow when the old filter becomes heavily clogged.
- Fitment is a common troubleshooting theme: one reviewer reports the filter was larger than expected and required compression/forcing; another reviewer reports it "actually fit the box" after other brands were undersized.
User Reviews & Q&A Summary:
- Reviews are mostly positive overall (20 reviews shown), with common themes:
- Fit & function: Many describe it as a perfect fit and comparable to the original filter; others warn actual dimensions may be slightly oversized for some cabinets.
- Replacement frequency varies: Some users report long service life (including reports of >12 months in certain setups), while others replace much more frequently due to pets/dust load.
- Value vs. cost: Several reviews note it isn't the cheapest option but is considered a good value when it fits correctly and lasts.
Specs
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| Material: | Synthetic |
|---|---|
| Size: | 20" x 20" x 5" |
| MERV: | 11 |
Contact
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Product Reviews
4.6 out of 20 reviews
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Most Liked Positive Review
Does it's job
These are the only filters that fit my unit. They don't last as long as they say, but, I do have a house full and several dogs. I change mine every month, and buying at a time , the cost came out to what I was paying for 3m filters before we upgraded to a 5" media filter.
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Most Liked Negative Review
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I would never buy this product again
The filter says 20 x 20 x 5, but it was larger and wider, and would not fit. I didn't want to go through the hassle of sending it back, because I needed one as soon as possible because my old one was really clogged. So I compressed and forced it in. I will actually talk with a rep the next time I order.
Showing 1-10 of 20 reviews
Great customer service
Love this company been using it for years. The customer service is top notch and very quick turnaround.
Summer
Ct
1 years ago
Verified Buyer
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I use this product in my unit pretty often.
These filters for my AC unit are great. They are the only ones I'll buy. Thank you Supply House.
Grandma
Griffin, Ga
2 years ago
Verified Buyer
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We continue to buy these filters for the price.
Great product for a great price.
Susieq
Harrodsburg KY
4 years ago
Verified Buyer
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Excellent, prompt service!
No need for generic substitutes with good pricing like this. Fast delivery too.
Homeowner Dan
Chesterton, Indiana
4 years ago
Verified Buyer
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Premium quality filter
I retrofit air handlers to use these as they last.
>12months and have consistent quality and sizing year after year. They are by no means cheap, but a very good value compared to competitor products. These have been my go-to for the past 5 years.
Aniel
New Jersey
4 years ago
Verified Buyer
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I would purchase again
Everything was great...fit perfectly !!!
I will order again !!!
Cat lady
Port st lucie fl
4 years ago
Verified Buyer
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I would buy this product, again.
This filter was exactly as described. It came quickly and was packaged well to protect the product.
Spencer
IN
4 years ago
Verified Buyer
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Would buy again
Fast delivery. Arrived in good condition. Appears to be same as original, so should perform the same. Perfect fit. Would order from Supply House again.
Kurt
Indiana
4 years ago
Verified Buyer
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BEWARE of Size
This 6FM2020 Merv 11 filter is actually 19 5/8" X 20 5/8" x 5". It may not fit your system because the 20 5/8" side is too large to fit.
I am in the process of returning them. I am confident in Supply House customer service as they are some of the best to deal with.
Joe from NC
North Carolina
4 years ago
Was this review helpful to you?
Filter that actually fits the box.
After buying other filters that were smaller than the advertised size it was good to find one that actually fit my filter box. Will buy again.
Dennis_1960
Tipton, In
5 years ago
Verified Buyer
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