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When to Replace Your Air Filters

Replacing dirty furnace filter in home
Replacing dirty furnace filter in home

A hotly debated topic in the HVAC world is that which concerns the frequency at which to change a home air filter.

An air filter is a piece of spun fiberglass or pleated paper framed by cardboard that lives in your return duct to keep dust, mold, bacteria, debris, and other damaging materials out of your air conditioning unit. It is a crucial piece of the puzzle that enables your unit to take in and circulate clean, cool air within your home.

What Is MERV, and How Important Is It?

Air filters have a minimum efficiency reporting value (MERV) that can clue you in as to what type and size of air pollutants the filter will be effective against. A filter with a MERV of 16 or below is acceptable for residential or general use. Any filter with a MERV from 17-20 is typically only used in sterile environments such as surgical operating rooms.

You can consult a trusted HVAC professional to help you choose a filter with the appropriate MERV for your system. A higher MERV, though it sounds preferable, can actually be damaging and too restricted if installed into the wrong kind of system, so be sure to do your research before choosing a higher MERV rating.

How Often Should I Change My Filter?

Experts everywhere agree that every three months is a reasonable amount of time between air filter changes in order to keep your unit working well and keep your power bill low. However, this timeline can be subjective according to climate, home location, and unit specifications. Those living in especially dusty climates should expect to change their filters more frequently, as accumulation of dirt will happen faster. Those with pets should also check and change their filters more often than those households that do not, as hair will clog up an air filter, rendering it ineffective quickly. Pet-friendly households should ideally change their air filters every two months.

If you have allergies or respiratory health conditions, consider changing your air filter even more frequently–every 20-45 days is recommended by experts based on your home situation and health needs. A general rule of thumb, too, is the more you use your home the more often you should change the filter. If you have a seasonal home that you only visit a few months out of the year, you can change those home filters every 9 months or even yearly. Additionally, if you work from home versus outside of the home, that can impact how often it needs to be changed as well.

Which Home Air Filter Is the Best?

It is crucial to choose the right size filter for your unit. You can find this information by simply using your current filter for scale or by consulting your unit’s manual. If you are unsure where to locate your filter, they are typically in a slot next to your furnace or air conditioning unit–however, in some systems, they may be scattered throughout your home. When in doubt, consult a professional to ensure you are making the right choice of filter. Beyond sizing, the actual type of filter doesn’t matter a whole lot, provided that it fits your particular needs. If you want a specific suggestion for your home and unit, get in touch with an HVAC professional for recommendations.

What Would Happen If I Didn’t Change My Filter at All?

The main function of an air filter is to keep debris out of your air conditioning unit, protecting the HVAC system from harm and ensuring that it works efficiently for a long time. Should you forget to change your air filter, it will eventually stop working properly, and your air conditioning unit can become vulnerable to damage from particles that will begin to find their way through. This will almost certainly cause much bigger, costlier issues down the road, such as damage to delicate parts of your unit or an overworked, worn-down system that could need replacing sooner rather than later.

Precision Air for Home Air Filter Expertise

Each home comes with its own specifications and set of needs, and each HVAC system is built differently, so the best home air filter for you will be different from that of your neighbor. In almost all situations, your best bet is always to consult a professional and get an honest, informed answer for the specific needs of your HVAC unit and your home. Contact Precision Air today to learn more about HVAC services and home air filter advice. 

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