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Air Filters

What Size Air Filter Do You Need?

Questions about air filter sizes?

  • How do you measure an air filter?

    An air filter’s size is described using three different measurements. The length, width, and depth of a filter are printed out in small numbers along the cardboard edge of a Filter King brand filter. But other filters may not have this information conveniently located, and you may need to find the measurements yourself. When doing so, check to see whether the filter is square or not. If it is not square, then the smallest-size side’s measurement goes first, followed by the next side, and then finally the depth measurement. 10x15x1 is a proper example of a correct size.

    Be sure to round the measurements up when you order new air filters. This rounded measurement is referred to as the nominal size and is used to match the right filter to its fitting air filter slot. By using the nominal size, you can order a new air filter that slides in and out of place with ease.

  • What is the most common size furnace filter?

    Currently, the most common size furnace filters are 10x20.

  • What size do furnace filters come in?

    There are hundreds of variant sizes of furnace filters because air filters and furnace are both the same. The only difference between the two is location. Filter King offers hundreds of different filter sizes capable of use for several home systems, including your furnace.

  • Where is the air filter on an AC unit?

    Depending on your AC unit, the air filter slot may be located in a hard to find location. First, try checking the blower compartment or return air duct where the air is cleaned before going through the unit. The unit itself may have the air filter inserted in a specific location.

  • Can I run my AC without a filter?

    Yes, but it is not recommended that you do so. There are several issues that occur for an AC unit, your home air system, and the home itself when an air filter is not installed.

  • What happens if the air filter is backwards?

    Air filters are built with a tight mesh weave that is designed to capture and absorb incoming particles. Air is brought through the porous side, and the mesh weaving allows it to flow in and out while being cleaned. When backwards, air has a harder time coming through, which means the system will require more energy to push it through the filter. When an air system is strained like this, it causes a rise in home energy billing and possible mechanical damage.

  • Will dirty air filter affect AC?

    Yes, over time dirty air filters will affect AC more and more. The longer a filter is left in a system, the dirtier it becomes, and the more pronounced the effects will be.

  • What happens if your AC filter is dirty?

    When your air filter is dirty, the mesh wearing that it consists of becomes clogged and full of dirt and debris. When this happens, the air that is supposed to flow forward through the filter has a harder time passing into the air system. The system will use more energy to try and push the air forward, straining itself and raising your energy billing in the process. The air inside your home may also start becoming stagnant and dirt over time since fresh air is unable to come in.

  • Are air filters important?

    Yes, they are very important to any air system they are in. Air systems have no way of knowing whether the air they are bringing in is clean or dirty. Air filters are essential to making sure that any air brought in is cleaned before entering the system. Without filtration, the air coming in from outside may contain any number of dust, debris pollutants, and allergens.

  • What are the symptoms of a bad air filter?

    When an air filter is bad, that can mean that it is either dirty or broken. When dirty, the symptoms include the air inside of a home drying out or stagnating and dust particles filling the air. If the air filter is broken or not working, the symptoms include any number of particles such as pollen, dust, mold, dust mites, bacteria, pet dander, smoke, and viruses.

  • How much is an air filter for House?

    The price of a single Filter King brand air filter varies depending on its measurements. However, the price falls when you buy multiple filters per order. Orders of two or more filters are also shipped for free.

  • How many air filters does a house have?

    This is entirely dependant on your home and the kind of AC system it has. Consult the owner’s guide for your home air system to understand how many air filters your home has and in what sizes.