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Furnace Filter

How Long Does a Furnace Filter Last?

Your HVAC filter is essential for keeping your furnace working smoothly and improving your home's indoor air quality. But, how long will one of them last? Its lifespan depends on what type of filter it is and how good your air quality is.

What Does Your Furnace Filter Do?

An air filter actually does a couple of jobs. It's top priority is to keep the heating system clean. Your furnace's blower fan pulls air into the return so that it can be reheated and circulated back out into the house. As the air passes through, it helps clean the air before arriving inside the heating system.

It can capture dust mites, pollen, smoke, pet dander, smog, mold spores, and household dust. These microscopic particles can land on the components in the furnace, making them work less efficiently. A build up of dust inside the heating system can lead to higher repair costs.

Its second job is to improve the air quality inside your home. All the pollen and dust that the filter captures comes straight out of the air you breathe. The more of these allergens captured, the better the air quality becomes.

What Kind of Filter Do You Have?

You need to consider the type of air filter you have:

  • HEPA: Helps capture up to 99% of particulates 0.3 microns or larger.
  • Pleated: Have more surface to capture the particulates.
  • Electrostatic: Are washable and long-lasting.
  • Fiberglass and Synthetic: Are good for protecting the furnace from dust.

Consult with an HVAC professional to decide what type of HVAC filter you should be using. Using the wrong filter can damage your heating system.

When Should You Replace It?

Always follow the manufacturer's recommendations for how often to replace filters. As a general rule, most filters should be replaced every 3 to 6 months. Thicker filters can last longer than thinner ones. Here's a rough estimate on how long one can last, based on its thickness.

  • Filters that are 1 to 2 inches thick should be replaced every 1 to 3 months.
  • Filters that are 3 to 4 inches thick should be replaced every 6 to 9 months.
  • Filters that are 5 to 6 inches thick should be replaced every 9 to 12 months.

The best practice according to HVAC professionals is to check it once a month to make sure the filter is still in good working order. Replace or clean them as needed.

Keep your furnace system in great condition. Improve the quality of air you breathe. Follow the manufacturer's recommendations on replacement. For more information about furnace filters, contact the professionals at Harwich Port Heating and Cooling.