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A Complete Guide To Different Types Of Furnace Filters

Not all furnace and air conditioner filters are created equal. It's often said that there are three primary types of furnace filters: cheap, moderately priced, and expensive. This would be factoring in only one aspect - sticker price - rather than looking closely at factors such as construction quality, useful lifespan, effectiveness at filtering out air contaminants and allergens, and other even more important considerations. 

In reality, there are many types of air filters (with a number of smaller variations between them). Different filters work differently and with varying degrees of success on different kinds of jobs. You want the cleanest indoor air regardless of what may be happening outside, so choose the most effective filter for the job, as outlined in this post.

First, let’s understand the Furnace Filter’s job. 

Filters used on furnace blower fans prevent clogging by protecting them from most of the dirt that is pulled into them by your furnace. In order to achieve this efficiently, the furnace filter traps dirt particles, thus preventing them from circulating throughout your home. However, what type of furnace filter do you choose will affect its life and performance. 

Types of Furnace Filters

To begin learning about furnace filters, let's first discuss the impact of HVAC filters and the materials used to make them. 

HEPA Filters

Usually, HEPA filters are used in separate air purifiers, but in some homes, they are integrated into the central air system, which keeps the air near the furnace clean. Some HEPA filters use ultraviolet light to kill live pathogens, which denatures and neutralizes cellular organisms as they traverse the filter. Others use activated carbon to boost their efficacy even further. High-efficiency particulate air, or HEPA, filters capture up to 99% of contaminants larger than 0.3 microns. They are excellent at eliminating indoor pollutants and create a healthier environment in your home.  

Fiberglass/Synthetic Filters

Fiberglass or synthetic furnace filter is inexpensive and disposable. The filters catch up to 80% of particles 50 microns or larger and 25% of particles between 3 and 10 microns in size. Using fiberglass/synthetic filters prevents dust and dirt from building up on heat exchangers, motors, and other parts of the system. These filters collect larger particles, keeping your furnace components clean. It also allows maximum airflow in your system, but they do not filter out harmful contaminants that can cause health problems for you in long-term. 

Polyester Filters

These filters come in medium sizes and are made of high-quality materials. Polyester filters trap between 80% and 95% of large particles. Four times more expensive than fiberglass or synthetic filters, polyester filters offer better protection against pollutants that may cause health problems. 

Pleated Filters

Designed with pleats, pleated filters offer a greater surface area for filtering. They are usually made of tightly woven polyester or cotton. A fiberglass filter has a weave that is loose enough to let you see through it, while a pleated filter is more solid-looking. The MERV ratings of these rugs vary from 6-12, depending on how tightly they are woven. You'll also need to replace this filter every one to three months, just like other disposable filters. As you raise your filter's rating, the harder it has to work, so you will likely see more frequent replacements. 

Electrostatic Filters

Electrostatic filters filter air by using fibers that charge themselves to attract particles. Depending on the requirements of your furnace, you can purchase disposable or washable electrostatic filters. MERV ratings for washable filters range from 4 to 10, and they last a great deal longer than average filters. When maintaining a washable filter, you must wash it with soap and water and let it dry completely before reinstalling it. Mold and mildew can grow if you install it before it has completely dried.

Carbon Filters

Carbon filters filter the air using carbon, or charcoal. Carbon is highly efficient at trapping gases in the air. Pollutant molecules attach to carbon molecules through a process called adsorption. If you're choosing a carbon filter, make sure it has a high carbon content and is activated. An activation process increases the surface area of carbon molecules, making them more effective. More carbon means more pollutants that the filter can absorb.

Also, consider the thickness. A thicker carbon filter will capture more particles than a thinner one. Since the air spends more time in a thicker filter, it gets cleaner. We call this dwell time.

What to Look for When Purchasing Filters

It is recommended that disposable furnace filters be replaced every three months. Depending on the filter, it may also need to be replaced every few weeks. Further, the air you breathe inside and outside your home may require you to replace your filter more frequently. Consult the filter manufacturer's recommendation to determine the replacement frequency.

Changing your filter regularly will ensure that your furnace is functioning properly. You will also enjoy excellent indoor air quality and low energy bills. As an added benefit, regular maintenance will ensure that your furnace's filter isn't clogged and will improve its lifespan.  

To find out what furnace filters type is best for you or how often you should change the filter, talk to an expert at US Home Filter. Depending on your needs and budget, our experts can help you select the right furnace filter.

Order now from US Home Filter and receive FREE SHIPPING on your order!

Selecting the filters that are right for your home can be difficult and confusing at times. At US Home Filter we understand this, which is why we offer an experienced staff to help answer any questions you may have. For personal assistance with your air filter needs, please contact us now online or call us at (855) 237-1673 and we will do our very best to assist you in selecting the right filter for your individual needs. We want to earn your business and we guarantee your satisfaction! Take advantage of our quality products, vast selection, low prices, and enjoy FREE SHIPPING on every air filter order within the Contiguous USA.

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