Lennox X6673 MERV 11 Filter Media 25 x 20 x 5 in - High Efficiency

In this review the Lennox X6673 MERV 11 filter media is judged as a practical, higher-efficiency replacement for a one-inch furnace filter in homes that want noticeably cleaner air without moving up to hospital-grade filters. The bottom line: it is for homeowners and renters who need a genuine Lennox OEM replacement that fits the X6660 HCC20-28 air cleaner and reliably captures fine particles before they reach HVAC coils. The reviewer found the build quality and fit meet expectations and the media captures very small particles for improved air quality.

Key Features

• 98% efficient media: Captures particles as small as 0.3 microns so dust and airborne irritants are reduced before they collect on coils.
• High-efficiency alternative: Offers better filtration than a typical one-inch filter while remaining compatible with existing housings.
• Exact fit for X6660: Designed to fit the X6660 HCC20-28 air cleaner so installation is straightforward and secure.
• OEM construction: Genuine Lennox parts and materials maintain original equipment standards for reliable performance.
• Practical dimensions: The labeled 20 in x 25 in x 5 in dimensions (actual 19-7/8 in x 24-3/4 in x 4-3/8 in) ensure it slides into standard trays without modification.

Who It's For

The X6673 is best for homeowners or maintenance-minded renters who want a durable, OEM replacement that improves indoor air by trapping very small particles and protecting HVAC coils. It suits anybody with an X6660 HCC20-28 air cleaner or a compatible slot that accepts a 5 in thick media filter, and who prefers a simple swap-in replacement over modifying filter frames.

This is not primarily aimed at users who need hospital-level filtration or those who require ultra-frequent changes for medically critical environments; those buyers should consider higher MERV or HEPA options. It also is unnecessary for systems that only accept thin one-inch disposable filters unless an adapter or specific housing is present.

Pros & Cons

Pros

• High particle capture efficiency improves overall air quality and reduces dust in living spaces.
• OEM build and dimensions provide an accurate, secure fit in compatible Lennox housings.
• Easy to install and remove, making routine replacement quick and practical.

Cons

• Thicker 5 in media requires a compatible air cleaner slot and will not work where only one-inch filters fit without an adapter.

Specifications

Our Verdict

The Lennox X6673 is a sensible buy for anyone with the X6660 air cleaner who wants a dependable OEM replacement that meaningfully improves filtration without complicating installation. It balances efficiency and convenience, offering strong particle capture and an accurate fit that make it good value for routine seasonal replacement.

Frequently Asked Questions

Will this filter fit my furnace?
It fits the X6660 HCC20-28 air cleaner and other housings that accept a 5 in thick media filter; it will not fit one-inch-only slots without an adapter.

How often should it be replaced?
Replacement frequency depends on use and local conditions, but seasonal replacement is typical; change more often in dusty or hard-use environments.

Is this a genuine Lennox part?
Yes, this is labeled as a genuine Lennox OEM furnace filter media designed to meet factory specifications.