When it’s time to change the oil filter in your car, a little indicator lets you know. That’s because changing the oil filter regularly is important – perhaps the single best thing you can do for car maintenance. It’s also true that changing the air filter on a recommended and regular basis is one of the best things you can do for your HVAC system.
But what happens when you don’t change your air filter? The answer is – nothing good.
Early stages: dirt in the air, dirt in the house
Air filters are designed to help keep your indoor air clean. Depending on their MERV rating (the Minimum Efficiency Reporting Value, a rating system for the effectiveness of an air filter - the higher the MERV rating, the better the filter is at capturing particles), your air filters trap all kinds of contaminants like lint, dust, smoke, mold, pet dander, pollen, and bacteria before they get through the ventilation system. Filtered air means you’re breathing better quality air and when “the dust settles”, there’s not much of it. Less dust in the air means less dust is getting re-circulated in the air as well. So, you get cleaner lungs and a cleaner house.
Later stages: system inefficiency and eventual failure
When air filters become dirty and clogged, it starts making things difficult for your HVAC system. It has to work harder to do the same job. That’s not only bad for your equipment but bad for your wallet as well. Your energy costs will go up because your equipment is struggling to push air through a dirty filter. Come to think of it, that’s bad for the environment as well – more energy consumption means a bigger carbon footprint.
Insufficient air flow can lead to uneven heating/cooling distribution, making pockets of uncomfortable air despite running things at full blast. It can also cause short cycling. Your system is supposed to cycle on and off periodically during the day, but when the air filter is dirty, it will cycle, cycle, cycle – eating up more energy and providing lower quality results.
Eventually dirty air filters can lead to system failure. The air filters also protect your HVAC equipment. Your system’s fan motor can become so dirty that it can cause the motor to overheat and perhaps even break down. Or if air filters are not regularly cleaned or replaced it can restrict your systems cold air flow inside the air conditioner, eventually causing ice to form on the coils and freeze up the unit.
Change those air filters
Depending on the model, it’s best to clean or change your filters on a regular basis for best performance and longest life of your HVAC system. If that’s one more thing you’ll struggle to remember, let a qualified HVAC professional take care of that as part of a routine maintenance contract. The air filter – and the maintenance contract – are cost effective ways to improve your home’s energy efficiency and prolong the life of your valuable HVAC equipment.