Atomic Filters Carriers an Extensive Collection of MERV 8, MERV 11 and MERV 13 Replacement Furnace Filters also known as Air Filters, Air Conditioner Filters, AC Filters or HVAC Filters. We carry a large variety of common and hard to find Air Filters Sizes. If you need a custom size contact us and we can make most sizes in 48 hour turn around time (business days).
$ 54.44 $ 69.95
18x24x4 air filters, furnace filters, air conditioner filters and HVAC filters. Replacement AC Furnace filters from Atomic Filters are high quality AC filters for a fraction of the price of low quality...
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When you are buying your air filter online most important thing to know is Air Filters have two sizes that you need to understand the Nominal size and the Actual Size. Not understanding these numbers often leads to consumers purchasing a filter that does not fit their Furnace or HVAC system.
Not understanding the Nominal Filter Size is the primary culprit for incorrectly purchased filters.The Nominal Size are the usually the dimensions used to Label the filter. For instance 16x20x1. These dimensions are a rounded value on the filters actual measurements. The actual measurements on this filter may be 15.5x19.5x.75, but that could vary by brand and manufacturer. So in order to make sure you have the correct size filter, especially if you are replacing with a different brand it is important to confirm the actual size on the filter. When purchasing filters on the internet the Nominal size is usually found the in the product title.
The actual size as you might have guessed are the actual dimensions of the filter by length, width and thickness. This size is often on the filter right below the Nominal size and is usually labeled as the actual size. When you are buying a filter online the actual size is sometime in the product bullet point or the product description. If your filter does not have actual dimensions on the outside of the filter, you can measure you filter to get the correct dimensions. Some brands have a foam gasket on the outside of the filter, in this case you will want to make sure you have a compatible actual size size and that it also has the foam to insure a snag fit.
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Furnace filters should fit securely but should not have to be forced into position. If you have to force the filter into its slot, then it is probably too big. Forcing an improper filter size in a filter can cause it to buckle, damaging the filter or reducing its ability to function properly. Filters are a smaller than their slot to allow for easy replacement. Some HVAC units may need a filter with dimensions that are unique or uncommon. In these cases, a custom filter needs to be ordered.