How often should HVAC filters be changed? Most air filter manufacturers and HVAC companies recommend changing your air filter every 30 – 90 days, depending on your home. That can vary based on what climate your home is in, if you have any pets, and the age of your system and equipment.

What filters should I use for HVAC?  Air filters come in different qualities and sizes; some have features that others don’t. In most cases, we advise using the filter recommended by the HVAC equipment manufacturer for that unit or just a basic pleated filter if you are unsure. All filters are assigned MERV ratings, which go from 1–20. MERV stands for Minimum Efficiency Reporting Value. 

What MERV rating is best for our home? The recommended MERV rating for a home is somewhere between 8-10. These filters will capture a large portion of the airborne particles and improve indoor air quality without making your energy costs rise significantly. These are not as restrictive as other filters. 

Are MERV 8 filters bad for HVAC? According to ASHRAE, MERV 8 filters aren’t the best choice for residential HVAC systems. Though MERV 8 is known to be effective at filtering out contaminants such as pollen, dust mites, sawdust, mold spores, and lint from the air, higher MERV ratings will clean the air even further. 

What about HEPA filters? HEPA filters remove most particles down to 0.3 microns in size. This fine filtering level provides more airflow resistance, which can strain a residential HVAC system. HEPA filters filter bacteria and viruses and are worth the extra money for those with respiratory conditions like emphysema. Superior filtering ability also comes at a premium price.

Do higher MERV filters restrict airflow? While the highest MERV ratings are the most effective for air quality, they can harm your HVAC system. A higher MERV rating means a higher resistance, which means less airflow.​​​

Do pleated air filters restrict air flow? Even though pleated fiberglass filters are very common and recommended often, there’s a misconception about the filters being able to cause damage to your unit because they supposedly restrict airflow.

Yes, pleated air filters do indeed restrict the airflow to your HVAC system; however, remember that the better filters are more restrictive, and an undersized return can cause the HVAC unit to have problems. The more expensive pleated residential filters filter out dust mites, pollen, mold and pet dander, and even bacteria. They are worth the money, especially for those with severe allergies.

Are fiberglass filters better than pleated filters? Fiberglass air filters are the most basic/cheapest type of air filter. Pleated air filters are much better. They can filter out smaller particles, and this is important for people with airborne sensitivities. The problem with cheap air filters is that they’re not as effective at removing dust and other contaminants from the air. This is especially true for homes with more people, pets, and maybe someone with a respiratory problem. You’ll have to replace them more often, which will cost you money in the long run. 

What happens if I don’t change my HVAC filter? Not changing your filter will cause you to have issues with your HVAC system. Your system will no longer be able to filter the air properly, letting dust and contaminants get into the AC from where the air begins to draw around the clogged filter. Dust jams the moving parts of an AC, such as fan motors, valves, and coils, and then airflow restrictions strain the system.