How is furnace filter efficiency measured?
Furnace filter efficiency is ascertained by the MERV rating. MERV stands for Minimum Efficiency Reporting Value. The MERV rating is accorded after putting a furnace filter through a strict test devised by ASHRAE i.e. the American Society of Heat, Refrigeration and Air-conditioning Engineers. MERV is a universal value by which a consumer is able to compare air filters. Home furnace filters have MERV ratings from 1 to 12. In plain words a higher MERV value would indicate a more efficient furnace filter than one with a lower rating.
