The average homeowner gives little thought to their heating & cooling
system filters. It can be hard enough just remembering to change them once a month. However, there are those that go further and buy the more expensive “allergen” filters that provide extreme filtration for their home. These types of filters are sold as a solution to allergic reactions from airborne contaminants. Unfortunately, using them creates a problem.
According to Phoenix home inspector David Swartz, these super high efficiency air filters create too much static (constant) pressure on the heating & cooling system. This excessive static pressure causes the equipment to work harder which results in premature failure of components like compressors, fan motors, etc. and higher energy costs. High efficiency systems are reduced to low or mid-efficiency systems by overly restrictive filters. As a property owner who is also paying for system upkeep and the electric bill, you need to be informed and make wise decisions regarding your filters.
“When performing a home inspection in Phoenix we often see these expensive and restrictive filters,” says Mr. Swartz. If you want to scrub the air for contaminants, he suggests you buy room air cleaners. Don’t ask your air conditioning system to do the job. You want your air conditioner/heater to change the temperature of the air in the home for the least amount of energy cost. It may be tempting to use the cheapest air filters (the ones that you can see through) in order to minimize the static pressure. “Don’t do that either”, says Swartz, “the job of the filter is to keep the evaporator coil clean.” Strike a balance and buy a filter in the moderate range, classified as a MERV 8. MERV is an industry standard rating for air filters that measures their ability to trap particles ranging in size from 3 to 10 microns. Home air filters commonly have MERV ratings from 1 to 12 — the higher the rating, the more efficient the air filter is at trapping particles.
We hope this information helps lower your energy costs and preserve your high efficiency equipment.