When it comes to air filters, size matters. The right size filter is essential for proper air flow and efficient operation of your HVAC system. But how do you know what size air filter you need? The first step is to measure the actual size of the filter. This is usually ¼ to ½ inch smaller than its nominal size.
To measure the length and width (L x W) of the filter, use a measuring tape. If the filter is not a square, the smallest measurement comes first. You can also use an air filter size chart to quickly find the right size. Most air conditioning and HVAC units use standard size filters, but some require a custom-sized air filter.
If the dimensions are too discolored to read or there's no air filter to look at, you'll need to measure it yourself. It's important that the filter fits snugly in the air cleaner compartment with a little space around the edges. Starting from actual sizes, round measurements to the nearest whole numbers when you order new air filters. Regulated, improperly sized, or installed filter frames can cause air leaks, significantly reducing filter efficiency.
In addition, if there is any resistance to airflow caused by the use of a filter that is not the correct size, it can cause unnecessary stress on the HVAC unit itself, which could damage the system equipment and increase your energy bills.Keep in mind that some HVAC systems require more than one air filter, so make sure you have the correct measurements for all of them. With the right size air filter, you can ensure your HVAC system runs efficiently and effectively.