It's important to replace your furnace filter at least every three months, even in summer. This is a general recommendation, but there are some factors that can shorten or extend the time between filter replacement intervals. If you notice that the filter is very discolored and covered with dust or hair, this is a sign that it needs to be replaced. Northerners whose furnaces have no rest for months may want to change their filter every 30 to 60 days, as more air is being drawn through the filter and it will clog more quickly.
Marking your calendar every 90 days or trying to remember the last time you changed your filter can be a challenge, which is why many furnace manufacturers recommend replacing it at the beginning of each new season. The filters are designed to protect the furnace from particles, and improving air quality is just one beneficial side effect. If outdoor temperatures are extremely cold or hot and your furnace or air conditioner is running non-stop to keep up to date, filters that should have lasted 90 days will need to be changed every 30 days. Three- or 4-inch filters can last 6 to 9 months, and filters up to 6 inches thick can be replaced once a year.
If it looks like you just cleaned the house and the surfaces in your house are dusty again, consider changing your furnace filter and consulting an HVAC professional. As a general rule to keep allergy sufferers as comfortable as possible, change the furnace filter every 30 to 60 days. When shopping for a new filter, there are a lot of options to choose from, many different types of filters to impact frequency changes. Dirty furnace filters are a disaster for heating and cooling equipment, home comfort, and indoor air quality.
In addition to keeping the HVAC system free of contaminants, furnace filters also help clean the indoor air you breathe. However, many people may not know that they also need to change the furnace filter at regular intervals. It's important to stay on top of this task in order to keep your home comfortable and your HVAC system running efficiently.