List Of The Most Common Furnace Filter Sizes

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Furnace filters keep your furnace working properly. You should change your furnace filter regularly to prevent malfunctions. 

Your furnace draws air in through air ducts, heats that air, and pushes the warm air through ducts throughout your house. It uses a blower fan to push air into each room in your house.

What are Furnace Filters?

Furnace filters filter out the gunk, primarily dust, from the air the furnace pulls in before it hits the blower fan. Having a new, clean, properly fitting furnace filter in place will improve the air quality of your home. 

When you are looking for furnace filters to purchase, pay attention to the Minimum Efficiency Reporting Value (MERV) rating. Higher rated furnace filters remove more contaminants from the air; however, they can cause your furnace to work harder, reducing its lifespan. 

What’s the Difference Between Air Filters, Furnace Filters, and AC Filters?

A furnace filter is the same as an AC filter. They are both referred to as air filters. 

Your home likely has central heat and AC. Even if your heating and cooling are separate, the filter will be the same if they share an air handler. You only need one filter for your air handler.

The same filter will work for both heating and cooling. Dust and gunk will be filtered out whether it is blowing out warm or cool air. 

What are Some Different Types of Filters?

There are many different types of filters. Pleated filters are made of paper and polyester. They are great for filtering out allergens. 

Another type of filter is the disposable fiberglass filter. These are typically the cheapest type of filter. Even though they are the cheapest, they are not necessarily the best option. Fiberglass filters are flimsier and do not filter out as much as pleated filters. Because of their poor quality, they need to be changed more frequently than pleated filters.

Washable filters give you the option of cleaning your filter rather than replacing it. They are permanent filters made of aluminum and plastic. Since you can vacuum or rinse off a permanent filter, they can last much longer than a disposable one; however, they are more expensive.

Electrostatic filters are great for trapping small particles because they self-charge, but they can be more dangerous.

Importance of Furnace Filters

Replacing your furnace filter regularly is essential because it removes contaminants from the air in your ducts before it blows it out into your home. If you don’t replace your air filter frequently, dust and dander will circulate through your home. This can be bad for your family’s health.

Replacing an old furnace filter with a clean one is an easy way to keep your furnace running efficiently. A more efficient furnace or air conditioning system will lower your energy bill and save you money.

You should also change your filter because if your furnace or AC system is using a clogged filter, it could cause it to malfunction. Your unit has to work harder to push air out, which can cause maintenance issues. A clean filter will help your system do what it’s supposed to do.

Does Furnace Filter Size Matter?

The size of your furnace filter is critical. You must get the right size for your furnace. 

If you get a furnace filter that is too big, it will not slide into place, and you won’t be able to use it at all. If you get a furnace filter that is too small, dust will blow through the edges where the filter doesn’t cover. 

What are the Standard Furnace Filter Sizes?

Common furnace filter sizes are 14×25, 16×20, 16×25, 20×25, and 25×25. The depth of these common sizes can range from one to six inches. 

How to Measure an Air Filter

The simplest way to figure out what size filter you need is to check the existing filter’s size. If you can’t see the old filter’s size, there is a simple way to measure it. 

With a tape measure, measure the length, width, and depth of the filter. Length is the smaller side if your filter is not square. Width is the length of the next side. Depth refers to the thickness of the filter. You may have to round the number up to the nearest whole number. 

How do I Know What Size Filter for my Furnace?

Furnace filter sizing can be confusing. This is because it is not measured simply by height and length. They are also measured by thickness.

Check the size of the filter that was already in place to find the right size filter. If you can’t figure out the old filter’s size, you can check the furnace manual. 

How do I Know What Size Air Filter I Need?

The simplest way to determine what size air filter you need is to check the filter’s size already in place. If there is no filter in place, you can check the furnace manual to see the best size. 

What Happens if you Use the Wrong Size Air Filter?

If the furnace filter you purchased is too big, it will not slide into place. This means you won’t be able to use it at all. If you get a too-small furnace filter, dust will blow through the edges where the filter doesn’t cover. 

It is important to use the correct size furnace filter. Too big won’t fit, and too small will allow dust and dirt to go through.

To make sure you have the correct size air filter, check the size of the filter that was already in place. Most filters have their size printed on the side. 

Having a clean air filter will allow your AC or heating system to run as efficiently as possible. To save money on your energy bill each month as well as on repairs, replace your furnace filter every other month.

If your family is experiencing problems with respiration, such as asthma or allergies, a dirty furnace filter may be the culprit. Change your furnace filter to improve the quality of air in your home.