How To Find The Right HVAC Filter Size

How to Make a Wood Vent Cover + the Best Air Filters air filter slot cover FilterLock Filter Slot Seal – Seal Cover for Any 1” Furnace Filter, Up To 25” Long · 4 out of 5 stars airport slot It eliminates air leakage at the filter slotdoor to improve indoor air quality and reduce energy consumption Features: Cover furnace filter slotdoor; Block

airport slot coordination essentially you want air being sucked from the return air vents through that filter, NOT bypassing around it If you can't buy, or get a cover