Phoenix Air Conditioning – Filters 101

ir Filters: What they Do and Why You Should Care

A properly-working Phoenix air conditioning system is one of the most important items a home can have. To ensure the system works effectively, Arizona homeowners must keep up on the necessary system maintenance. One of the easiest ways to maintain the system is to change the filter regularly – about once a month for disposable filters.

How the Air Filter Does Its Job

You have no doubt seen that fuzzy, cardboard looking piece inside the grills of your Phoenix or Tucson air conditioning system. That’s the filter. The filter serves two purposes: keep the air conditioning system clean and remove particles from the air.

As an air conditioner brings air into your home, that air is cooled by blowing it over a set of cold pipes called an evaporator coil. The air goes from the evaporator coil to the filter, and the filter begins doing its job of catching airborne particles such as dust, pollen, mold, and bacteria. These particles would otherwise go into your home, leading to polluted air and problems for those with allergies.

Dangers of a Dirty Filter

Not only can a dirty filter become a source of poor air quality and pollution, it also decreases air conditioning and energy efficiency. According to, replacing a dirty, clogged filter with a clean one can lower your air Phoenix air conditioning system’s energy consumption by 5 to 15 percent.

To be sure you have clean air and an efficient system, it’s best to inspect, clean, or change your air filters once a month. According to, a dirty filter can increase energy costs and damage your equipment, leading to early failure. Changing a filter is easy to do and disposable filters can be purchased at a reasonable price from a home improvement store.

Choosing the Right Filter

Air filters are measured in MERV (Minimum Efficiency Reporting Value) ratings. This rating tells you the ability of an air conditioning filter to remove dust from the air as it passes through the filter. Therefore, a higher MERV rating means fewer dust particles and other airborne contaminants pass through the filter. Most residential air filters have a MERV rating of one to four, while commercial cooling system filters have a five or more MERV rating.

Fiberglass air filters –These capture large particles like lint and dust and are the least expensive type of disposable filter. But you get what you pay for. These filters protect your HVAC unit but won’t improve indoor air quality much.

Pleated air filters – Lab tests of these commonly-used filters showed removal of up to 90 percent of mold spores and pet dander, according to The Washington Post.

Washable air filters – These filters usually have a very low MERV rating and require more maintenance. They are more susceptible to fungus and bacteria, which can escape and circulate throughout your home.

High-efficiency air filters – These filters remove the highest level of air pollutants and have the highest MERV ratings. They are most often used in commercial or industrial settings.

To learn more about air filters, including instructions on how to change your filter, view the Tech Tip video from Tucson and Phoenix air conditioning contractor Chas Roberts. Or schedule an appointment with an experienced Chas Roberts technician. Visit Chas or call (602) 943-3426 in Phoenix, (520) 618-1884 in Tucson or (505) 264-7257 in New Mexico.