The True Purpose of Air Filters in your HVAC System
There’s a ton of content around the internet about air filters and HVAC systems. It seems like everyone recommends replacing the filter regularly, but the reasons for doing so are often varied. Some articles talk about benefits of different filters, different particle sizes that pass through, HEPA level filters, supposed air quality improvements around your home and other upgrades. But how much of that is true? Let’s break it down.
You Have One Filter for your AC and Furnace
Air conditioners and furnaces operate as one system together. The intake all passes through to one filter, so you don’t need to replace filters in multiple areas. It’s usually located right next to your blower motor in your furnace, so normally you will find it there. If you think it strange that your AC filter is by the furnace, just remember that the air conditioner and heater are a team.
Filters Protect the Equipment, Not Your Lungs
The truth is that your filter is there to protect your HVAC system, not your health. This makes sense – in most homes air is entering and exiting the home through a variety of other methods. When you open the door or leave a window open, fresh air is introduced into the home that does not pass through the HVAC system and therefore is not filtered by your HVAC filter.
What the filter does is prevent dust, dirt, debris and other particulates from hitting the sensitive components of your HVAC equipment. It does prevent more dust from being blown through your ductwork and dispersed through the house, but it’s not going to purify all the air in your home.
The exception to this might be doomsday bunkers or extremely airtight homes that intake most of the fresh air through the HVAC system, but in most cases, this is not how homes work today.
Upgrading the Filter May Damage Your Equipment
You may want to think twice before buying a HEPA filter for your system. When the coronavirus pandemic started, searches for HEPA filters and other indoor air quality products skyrocketed. It’s true these filters are what are used in hospitals, but your typical residential HVAC system does not have components designed to work with a HEPA filter. HEPA filters have tighter weaves, which means it catches tiny particles and keeps the air remarkably clean. Because the weave is tighter, the airflow is restricted. This means your blower motor and other components have to work harder to draw the correct amount of air through the system, leading to greater wear and tear over time.
The same effect occurs if you leave your filter alone too long and it collects too much dust and dirt. You may be looking at a furnace repair due to low airflow during a cold winter night, which normally requires a professional to fix.
Keep it Clean, Keep it Open
If you’re really concerned about air quality in the home, follow the EPA’s guidance on improved ventilation and source control. Although your HVAC system should remain protected by your filter, your lungs will benefit from opening a few windows and letting the outdoors in.
partnered post • cc-licensed image by HomeSpot