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The Different Types of Furnace Filters

What are the Different Types of Furnace Filters?

A clean and well-functioning furnace filter is essential for purifying the air inside your home. Keeping the filter clean and changing it regularly supports your heating system to work efficiently, while keeping your lungs healthy and your energy costs low!

How often you need to change your filter will depend on the type of filter you’re using, how frequently your furnace is running, and the amount of dust, pet dander, and allergens in the air. Read on to get familiar with furnace filters, find the type of filter that’s best for you, and optimize your maintenance schedule.

How to Know if it’s Time to Change your Furnace Filter 

There’s no one-size-fits-all answer about how often you should change your furnace filter. It will vary depending on whether or not you have pets or smokers in your home, how frequently you open doors and windows or run the heater fan, and the amount of dust or allergens in the air.

A good rule of thumb is to change 1–2-inch filters every three months, 4-inch filters every six months, and 5-inch filters every 12 months. If you have pets, open windows and doors often, or frequently run the heater fan – consider more frequent air filter changes.

If all else fails, here are four tell-tale signs that your air filter needs to be changed:

  • The heating system is running more frequently than usual
  • You notice more dust accumulating in your home
  • The filter is visibly dirty
  • Strange or burning smells.

Selecting a Furnace Filter 

How do you find a furnace filter that suits you and your unique needs? It starts with understanding some of the key factors that impact how long your furnace filter lasts.

Simply put, the filter’s job is to protect the internal components of the furnace from airborne particles that are drawn in through the return ducts. Installing the ideal type of filter and changing it regularly will optimize your furnace’s performance and increase its lifespan.

If you find yourself in a situation that increases the amount of dust and debris in your home, or you have lung sensitivities that require high air quality, you may want to consider a stronger, more durable filter. Your choice may also be impacted by how often you want to change the filter, its size, and the cost.

Get educated on the most common types of furnace filters and choose the one that is the best fit for you!

Types of Furnace Filters 

Fiberglass Filters 

Fiberglass and synthetic filters are the most affordable options. Highly effective at capturing particles that are 50 microns or larger, these filters fall short in capturing smaller particles that can contaminate your air. Considered minimum protection, fiberglass filters are disposable, flimsy and need to be replaced monthly. Although they are effective at maximizing airflow to your furnace, they produce a lot of waste and are not optimal for your health.

Pleated Filters 

Pleated filters are the most commonly used type of furnace filter. As a disposable option, they are more efficient and last longer than fiberglass filters. Available in a variety of sizes, these filters are comprised of paper and polyester and effectively filter out pollutants as small as 0.3 micron in size, including harmful bacteria, viruses, and allergens. They require less maintenance as they can be replaced every three months, making them an affordable and effective option for most homes.

Washable Filters 

Some types of furnace filters come in both disposable and washable options. A washable filter needs to be thoroughly cleaned every month, and allowed to completely dry before it’s reinstalled, to prevent mold and mildew.

Electrostatic Filters

Electrostatic filters function through static electricity. Through a self-charging mechanism, the filter attracts airborne particles and holds them with a static charge, removing harmful toxins and pollutants from your environment. These filters are available in both disposable and washable options, with the washable option lasting much longer than the average filter – as long as you keep up with maintenance and care.

HEPA Filters 

Known as high energy efficiency particulate air filters, a HEPA filter can trap up to 99% of particulates in the air that are 0.3 microns or larger. Although they are superior in eliminating indoor pollutants and maximizing air quality, they can reduce air flow in the furnace which may increase your energy usage and in turn your utility bill.

To learn more about how to stay warm and keep on top of your heating system this winter, visit our furnace FAQs or 7 Common Heating Problems and How to Fix Them. If you’re looking for more clarity or expert advice on which furnace filter is best for you, call the experts at Ashton, we’re here to help!

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