What Furnace Filter To Buy May 2026

: If you use a 1-inch filter in a slot designed for 4-inch filters, it will leak air and bypass filtration. Filterbuy notes that incorrect thickness can degrade air quality and strain your system.

The first step is checking your current filter for its (e.g., 20x25x1), which is printed on the side. what furnace filter to buy

: MERV 11 is recommended for multi-pet homes or those with seasonal allergies, as it captures finer dander and pollen. : If you use a 1-inch filter in

The Minimum Efficiency Reporting Value (MERV) tells you how well a filter traps particles. MERV Rating Large particles (lint, dust) Protecting the furnace motor only. MERV 5–8 Mold spores, hair, pet dander Standard homes with no pets or allergies. MERV 11–13 Smoke, bacteria, smog Homes with pets, smokers, or allergy sufferers. MERV 14–16 Viruses, fine tobacco smoke Highly sensitive individuals or clinics. 3. Choose Your Filter Material : MERV 11 is recommended for multi-pet homes