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Home > Air Filtration > All Air Filters > Fiberglass Disposable Air Filter 18" x 21" x 1" Robust Double Strut

Fiberglass Disposable Air Filter 18" x 21" x 1" Robust Double Strut Construction with high Dust Holding Capacity

Item #:18X21X1

Manufacturer Item: 18X21X1 DISPOSABLE

Manufacturer: AIR FILTERS

Glassfloss 18X21X1 MERV 4 Standard Fiberglass Air Filter 18" x 21" x 1"

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How often do I need to change my air filter?

There are many factors that can determine when an air filter should be changed. How often the HVAC unit runs, air quality, humidity and other factors can vary greatly from application to application. For most 1, 2 and 4 deep panel or pleated style filters, it is usually recommended to change the filter every 2-3 months. In many commercial and industrial applications static pressure can be monitored and the filters can be changed when they reach their recommended final resistance in inches of water gauge.

What is MERV?

MERV stands for: Minimum Efficiency Reporting Value. MERV is part of the ASHRAE 52.2 Test Standard that determines the ability of an air filter to remove particles of a specific size from an air stream. Air filters can have a MERV of 1 to 16; the higher the MERV, the more efficient the filter is at capturing particles