4 Things to Know Before Replacing Your Indoor Air Filters

If you only do one maintenance task on your HVAC system yourself, we recommend replacing your indoor air filters. Generally, they are located inside one or more return air grills inside your home. These are the covered grills where your indoor air conditioner intakes air to cool or heat and then to distribute around your home. In general, these should be replaced every 1-3 months and generally requires no tools. Simply pop open the grill, pull out the old filter and replace it with the new filter that is the same size. If you need pictures for how to change your indoor air filters, we have a tutorial that makes it easy.

Air Filters and Allergies

It is a common misconception that replaceable indoor air filters on your central air or heat pump system will reduce allergens in the home and cause a significant reduction in allergy symptoms. While they do fulfill an important function of keeping dust and pollen out of your home’s ductwork and from recirculating throughout your home, this passive method of air filtration can only be modestly successful at improving your home’s overall air quality. Its scope is at best limited when it is the only method used to combat allergens. Plenty of marketing slogans are used to sell the highest end versions of these – and you can spend a bundle up to $50-70/each!  The added value for the filters that filter everything really don’t justify the added costs.

Avoid High-MERV Filters

Another reason we do not often recommend High-MERV filters is they can freeze up your system and cause it to quit.  MERV stands for Minimum Efficiency Reporting Value and indicates how efficient a filter is at capturing particles from the air. Lower MERV filters remove larger particles and allow a lot of air to flow through them. Higher MERV filters, on the other hand, are more densely woven and remove smaller particles from the air and as a consequence, it is harder for air to get through the tiny spaces. This can cause pressure to build up in your system because your air conditioner has to work harder to draw in enough air to run properly. If your system can’t get enough air, it causes an imbalance which requires your system to run longer to get the air it needs. That imbalance can cause the system to freeze up and quit working in the warmer months. In the cooler months, it can cause your heater or furnace to run too hot. This scenario is most common in the warmer months, but it can happen any time of year and it can also happen if you forget to replace your filters and they get clogged.  We generally recommend filters rated MERV 8-11 and no specific brand.

Passive Versus Active Filtration

Disposable air filters in are an important first line of defense toward keeping your HVAC system clean and the dust and pollen from daily living from accumulating in the home. For the best performance and removal of allergens, such as mold, pollen, viruses, pet dander, dust, and more from the air, we generally recommend adding an in-duct media filter, ultraviolet lights in the evaporator coil, and/or an active air purifier. Active air purifiers, whether installed in-duct inside your HVAC system or a free-standing unit, pull out very small particles from the air, actively improving air that is circulated throughout your home. Any combination of these methods can result in a much improved air quality in your home over and beyond what disposable filters can accomplish by themselves.

Save Money & Hassle

Do yourself a favor and purchase your indoor air filters in bulk, from your nearest home improvement store or online. If a filter is rated a MERV 11, it is required to hold to the those standards so you don’t need to spend extra money for brands with the fancy packaging unless you want to. I like to write on the filter when I installed it, so I know when to change it. Then, you can set a reminder in your daily planner for 3 months from now, or set a reminder using your favorite calendar app on your phone. Remember, that your indoor air filters perform best if you regularly change them every three months and more often during allergy season.

Need Help With Maintenance?

Terry’s A/C & Heating can help you if you have questions about filters or the best way to purify the air in your home. Give us a call at (281) 495-7830 to schedule an appointment and we’ll bring our services to your home or office in the Southwest Houston, Katy, Richmond and surrounding area. We provide top-notch service and expert repairs and installations to keep your home or office comfortable any time of year. Find out how we are different and what specials we have on tap.