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Whole House Air Filter: All You Need To Know

Air filters exist in a huge variety of sizes, but you'll sometimes find that it's challenging to find the exact one you need in a store. Air filters for the home are very common obviously, but how do I really measure the correct size? And what's the exact MERV grade that my system requires to perform at it's best and most efficiently? So, here's basically everything you need to know about whole-house air filters and selecting the right replacement filters.

Why Do You Need Such a Big Air Filter?

The home air filter is perhaps the least standardized product in the world. That's why nobody can find their size at the hardware store, and that's why we offer such a vast array of different sizes.

Whole-house air filters are one type that can be particularly difficult to locate at local stores, as they are quite different from the usual one-inch filters. You may have heard them called whole-house air purifiers. HVAC systems include air purifiers, but they are not part of them. However, the air filters are part of your system and are not optional. 

By definition, the concept is defined by the need for only one filter per household. It's the most common setup, but sometimes it doesn't hold true in practice. Your whole house filter requirements depend on how your HVAC system is configured, which could differ from one system to another.

When you install Whole House Air Filter, air handler units (AHU) regulate and circulate air. Basically, it controls your air. Some houses may have multiple air handlers to regulate the temperature in different areas separately based on the house's size. 

Whole-house systems can be installed if you have ductwork and a forced-air system.

What Do Whole House Air Filters Look Like?

A whole house filter is defined as a filter with a thickness of three inches or more. The most commonly available thicknesses are four and five inches, but three- and six-inch options are also available. They are similar to common one-inch pleated filters but have one difference. Compared to one-inch filters, whole-house filters have a much larger surface area due to the deep-v pleats that fill their nearly half-foot thick frame.  

In general, the "nominal size" of an air filter is the rounded size, based on how each dimension is rounded up or down. There is a standard undercut on one-inch filters, which means that all one-inch filters measure ¼" to ½" shorter than their nominal size, but there is no standard undercut on whole house filters. This means that two 25x20x5 filters from different manufacturers may have completely different sizes. Make sure you know the exact size you need, or you may end up with a whole house filter that doesn't fit.

What Makes a Whole House Air Filter So Different? 

A whole house filter and a regular one-inch filter differ primarily in their longevity, in addition to their appearance. Unlike personal filters, a whole house filter does not require constant replacement due to its massive surface area. Often times the manufacturers recommend replacements every six months instead of every three, and sometimes, even once a year is sufficient. 

In order to determine how often your filter needs to be replaced, you need to consider what factors may influence the quality of your air. What is a replacement frequency for the living situation without pets? Six months should be enough. Do you have a lot of pets and live in a polluted area? It might need to be changed more frequently, like every three to four months. 

Is a Whole House Filter More Expensive?

Indeed. On average, a whole house filter costs between $25 and $35, and some go as high as $40. They cost more than one-inch air filters, but they also need to be changed less frequently and sometimes only one at a time. Despite the fact that whole-house air filters may cost more than smaller ones, you may spend less on air filters per year (depending on your house).  

Where Can You Fit the Whole House Filter? 

Unlike other air filters, a whole house filter does not fit in your wall. Air filters are put into the ductwork directly in front of the HVAC system. There are several filter varieties that fit into the housing before being installed, while others are inserted directly into a slot in the duct.

Although a whole house filter sounds wonderful, you might not actually require one. If your home uses whole house air filters, then you can use them. In the event your home doesn't already have the system installed, you will obviously need to install a new one or upgrade your existing one. Prior to deciding to upgrade your system, you'll need to consider the installation and upgrade costs.

Need Personal Assistance While Choosing a Whole House Filter? 

Us Home Filter provides air conditioning and heating filters to customers throughout the United States. So, once you decide you want to install a whole house filter, you might get confused on the sizes, brands, and much more. In such cases, our experts can help you. You can call us at 1-855-435-9600 or contact us online today! With us, you'll receive high-quality filters, a large assortment to meet your needs, reasonable prices, and FREE SHIPPING for purchases within the contiguous United States. So, get in touch now!

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