The much-debated question about your home heating, ventilation, and air conditioning (HVAC) system is: how often should the filter be changed? There is no one answer to this question, as there are many factors to consider in changing your filter. These include:

• Type of filter being used – there is a clear distinction between a 1” filter compared to a pleated MERV 16 filter that is 5” thick.
• Type of furnace and AC – if you have a new high-efficiency furnace and/or air conditioner it will help increase the lifespan of your filter in comparison to a 15+ year old system that is tired and needs all the help it can get.
• House specific – the size of your home, where you live, how many people and pets are living in your home all factor into how long your filter will function at an optimal level.
• Season – the filter efficiency is also dependent on the time of year and how often you run your equipment.

There are many different sources you can reference for guidelines to this question. According to energystar.gov and Consumer Reports the average filter should be checked every month and replaced at least every three months.

Regardless of what type of filter you have, and how often you choose to change your filter, all homeowners should understand why a filter needs to be replaced. Heating and cooling systems have a filter to remove airborne particles before they reach the blower motor and cause damage. The filter also ensures that the air being pushed through your vents is clean and dust-free. When the filter is replaced often, it allows your furnace and air conditioner to run at optimal efficiency, and that is reflected in your monthly energy bill.

For all instructions as to how to replace the filter in your HVAC system please reference your owner’s manual, or see our FAQ post “How do I change my furnace air filter?“