Air Filters – Understanding Size, Types & MERV

Neglecting to change your air filter can not only decrease the efficiency of your system, but it can also increase poor air quality or even cause your system to fail prematurely – causing high repair bills! You can begin improving the efficiency of your system and the air quality in your home immediately just by changing or upgrading your air filter. There are many factors to consider when buying that replacement filter.

First of all, some filters are the throw away type and others can be cleaned and re-used. Some filters are pleated to have more surface area to catch more particles. Other cleanable types of air filters can be used for years before replacing. Either way, you should chose a filter based on your individual needs. If you go into your local hardware store or one of the big box stores, like Home Deport or Lowes, you will more than likely see filters with a MERV (Minimum Efficiency Reporting Value) rating. The higher the MERV rating, the more particles are bring removed. They can range anywhere from $1-$20. Read the fine print and discover what contaminants are actually filtered from the air and match that data to your particular needs. For instance, if you are allergic to animal dander, a simple inexpensive, disposable filter might be all you require. Just be sure that you change them monthly during the heating and cooling seasons. If you wish to eliminate odors you’ll have to step up to a much more sophisticated electro-static type of filter – one that has been electrically charged to pull particles right out of the air.

Secondly, you must be sure to install a properly-sized filter that fits snugly in the furnace return air frame. Doing this ensures that air cannot pass around the filter, defeating its purpose. The frame of the filter itself should also be sturdy so that the filter does not collapse or bend allowing air to pass around it without filtration. The thickness of the filter typically ranges from 1″ to 4″ so be sure buy the exact replacement size listed in the system’s Owner’s Manual.

On another note, there are also very efficient media filters and electronic air filtration systems that you can have installed by an HVAC contractor, like UGI Heating, Cooling & Plumbing. When choosing a more advanced air filtration system it is wise to select a local Heating and Cooling company that has the experience to not only fully advise you on all your options, but be able to correctly install and service the system down the road.

As we continue to insulate our houses to a greater degree it becomes increasingly important to filter your indoor air to fight germs and bacteria and all the day-to-day household cleaning products. Visit to for more information on filter ratings and recommendations or call the professionals at UGI Heating, Cooling and Plumbing and rely on their 120 plus years of Indoor Air Quality (IAQ) experience.