High-quality furnace filters are made of superior materials compared to their cheaper counterparts. They are usually constructed from fiberglass, which is a porous material that can trap more dust and pollen than other materials such as cardboard or paper. Nortek Environmental, Inc. recommends that all customers purchase the least expensive fiberglass filters instead of the more costly pleated filters.
The primary reason for this recommendation is that fiberglass filters do not restrict air flow to the oven as much as pleated filters. Oven filters not only prevent the system from becoming clogged with dirt and dust, but they also purify the air in your home. There are several factors to consider when selecting the best air filter for your oven (or central air conditioning unit). The suggestion of fiberglass air filters by HVAC technicians is due to the number of homeowners who do not replace their air filters.
It turns out that both ovens and air conditioning units use the same filters and perform the same functions. Companies market and sell their HEPA filters at a higher price to make them appear superior. An ASHRAE study found that filters with a MERV rating of 4 or less met this standard, while a filter with a MERV rating of 8 doubled the pressure drop and a MERV rating of 11 tripled it. Companies use inflated HEPA filter prices to convince you that your HEPA filter is better than others.
Although these filters may be more expensive, the upside is that you don't have to buy them as often as filters that need to be changed monthly. Not only do filters remove dust allergens, mold spores, and other pollutants from the air your family breathes, but they also filter out fine dirt particles that can reduce the performance of the HVAC system itself. While these high MERV filters are great for filtering debris and cleaning the air in your home, they reduce the air pressure in your duct system. The main purpose of an oven filter is to block large particles and debris from entering the oven, which could cause damage to the oven. You'll notice that it's much harder to breathe when you hold the oven's pleated filter against your mouth.
Filters become dirty over time and layers of dirt and debris soon cover the holes between the woven air filter mesh. Household HVAC air filters are rated based on their MERV rating, with most household filters between 1 and 13 (more than 13 are for HEPA filters). Changing your boiler filter on a monthly basis is one of the most important general maintenance tasks you can perform for your home's HVAC system.
