Why it matters
The AIRx Replacement Filter for Lennox X6673 is a pleated furnace and air conditioner filter rated MERV 8.
MERV 8 is the common equipment-protection grade: it catches dust, lint, pollen and most pet hair with very little airflow restriction.
Deep pleated filters hold several times the media of a 1-inch filter, so they run with less resistance and last longer.
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 20x25x5 size; order by the size printed on your old filter's frame.
The AIRx listing names 2 filters per box.
Compared with the AIRx MERV 13 1-inch Furnace Filter: MERV rating 8 here vs 13.
Who it's for, and who should skip it
Good fit if
- Everyday dust and equipment protection
- Homes that change filters on schedule
Look elsewhere if
- Smoke or fine-particle control
Pros and cons
Pros
- MERV 8
Cons
- Catches little of the finest smoke and dust
- 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 | X6673 Air Filter 2 Pack | Retailer |
|---|---|---|
| MERV rating | 8 | Retailer |
Alternatives worth comparing
More hvac and furnace filters we cover
- Honeywell MERV 12 4-inch Furnace Filter
- Nordic Pure MERV 12 1-inch Carbon Furnace Filter
- True Blue Allergen MERV 11 Air Filter
- Amazon Basics MERV 11 1-inch Furnace Filter
- Aprilaire MERV 11 Furnace Filter
All hvac and furnace filters, compared in one table · Every AIRx product we cover
Final verdict
A well-matched choice for everyday dust and equipment protection. Confirm the model it fits before ordering.
Where to buy
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