Why it matters
The BNX MERV 13 1-inch Furnace Filter is a pleated furnace and air conditioner filter rated MERV 13.
MERV 13 is the highest grade most homes use: it catches a good share of fine particles (0.3 to 1 micron), including much wildfire smoke, but adds more airflow resistance, especially in 1-inch frames.
As general guidance, check a 1-inch filter monthly and change it every one to three months; deeper 4- and 5-inch filters usually last six to twelve months.
This listing is the 20x20x1 size; order by the size printed on your old filter's frame.
The BNX listing names made in the USA and 4 filters per box.
Compared with the BNX TruFilter MERV 8 Air Filter: MERV rating 13 here vs 8.
Who it's for, and who should skip it
Good fit if
- Wildfire smoke season
- Allergy households
- Homes that change filters on schedule
Look elsewhere if
- Systems that whistle or short-cycle with denser filters
Pros and cons
Pros
- MERV 13
Cons
- Denser media: check that your system handles MERV 13
- Measure your slot: nominal and actual sizes differ
Limitations to weigh
- Specifications are the maker's or seller's own figures; check fit against your equipment's model number and the actual size.
Specifications
The bracket shows where each figure comes from.
| Model number | BNX-M13-20x20x1-4P | Retailer |
|---|---|---|
| MERV rating | 13 | Retailer |
| Dimensions (seller) | 19.68"L x 19.68"W x 0.75"Th | Retailer |
| Compatible devices | Furnace | Retailer |
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Final verdict
A solid choice for wildfire smoke season. Confirm the model it fits before ordering.
Where to buy
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