For optimal performance, it's important to keep your furnace filter clean and replace it regularly. But how often should you change it? The answer depends on a few factors, such as the size of the filter and the amount of dust in your home. In general, filters that are 3 to 4 inches should be changed every 6 to 9 months, while filters that are 5 to 6 inches should be changed every 9 to 12 months. However, if you use your HVAC system frequently or if your home has a lot of dust, you may need to change the filter more often.
For example, one- and two-inch filters should be changed every month, four-inch filters every two months, and five-inch filters every three months. It's also important to use the right type of filter for your furnace. Most air filtration experts recommend using a filter with a MERV rating of 12, such as the Nordic Pure filter (available on Amazon). This will help ensure that your HVAC system is working efficiently and that your indoor air is safe and healthy.
To help extend the life of your filter and improve efficiency between changes, gently vacuum the inlet side of the filter when you check it. And if you can't seem to remember when to change it, a good rule of thumb is to replace your furnace filter every time the seasons change.