How Often Do I Need to Change a Furnace Filter?

Updated: February 2024
Have you ever wondered how often should you change your furnace filters? Changing your furnace filter on a regular basis helps to improve the indoor air quality in your home. Filters can be filled with dust and other contaminants making them unable to trap new particles.

If you don’t change your filter, the air impurities are left to circulate in your home, and you will be breathing them in. Furthermore, the motor of a dirty furnace filter runs more, and it becomes less energy efficient.

Minimum Efficiency Reporting Values, or MERVs, report a filter’s ability to capture larger particles between 0.3 and 10 microns. The basic recommendation for furnace filters replacement is every 3-4 months for MERV 8, every 6 months MERV 10 and 11 and every year for MERV 16.

There are other several factors to consider when determining when to change your home air filter. Here are some key guidelines that can help you determine how often to change your furnace filters.

How Often Do I Need to Change a Furnace Filter?

What type of Filter do you have?
The type of filter you have installed in your home is a major influence of how often you need to change it. Various filter types are different in make, form, and thickness.  A fiberglass filter requires regular changing compared to a pleated filter. Likewise, a 1-inch pleated filter will need more frequent change as opposed to a 4-inch pleated filter which can last up to six months before needing to be replaced because they have more area for particles to build up.


Does anyone suffer from Allergies?
If anyone suffers from allergies or asthma in your home, frequent changing of filters is recommended to help trap more allergens that may trigger symptoms if left to circulate in your home.


Do you have pets in your house?
Pets shed their fur and dander which may get stuck in the filters. The more pets you have in your home, the more often you’ll need to change your furnace filters.  If you have shedding pets like cats and dogs, it is recommended that you inspect your air filter every month to enhance the performance of your air conditioning system. Also depending on the season, you may need to change the filter more during hotter months since animals shed more when it’s hot.


Do you have Smokers in your house?
Having a smoker and the number of smokers in your home will influence how often you change your filters. Smoke can cause damage to the filter and the more smokers you have, the more frequently you’ll need to change the filters.


How dusty is your home?
Excess dust and dirt may clog air conditioner’s filter and affect its performance.  If you get a lot of dust more frequently in your home, you’ll need to change your filter more often depending on the size of the filter.


If you are concerned about the air quality in your home, we can help! We provide air quality testing services so that you can have peace of mind in your daily life.

Do you need furnace maintenance? Wellmann Heating & Air Inc. offers you comprehensive filter services to improve your home energy efficiency. We are a FAD (Factory Authorized Dealer) with Certified NATE Technicians and Installers who offer 100% satisfaction on all new air conditioning & heating system installation and maintenance.

Contact us!