One of the most important steps in furnace maintenance also happens to be one of the easiest: changing your furnace filter. Experts recommend changing filters every 3 to 6 months, depending on the size of the filter and home, whether you have pets, and the amount of dust in the area you live. When it comes time to swap a used filter for a fresh one, how do you decide what to pick? Here are a few factors to consider as you choose the most effective furnace filter for your home.
Look at MERV ratings
Every furnace filter comes with a MERV rating. MERV is the abbreviation for Minimum Efficiency Reporting Value. The MERV scale was designed by industry experts to set a consistent value on a filter's performance and efficiency. The MERV scale ranges from 1 to 20. The higher the rating, the better the filter is at stopping particles. But higher numbers don't necessarily lead to greater energy savings because the better the filter is at stopping particles, the more airflow is restricted. So you have to consider what's most important to you when looking at MERV ratings. If you live in an area with a lot of pollution, a higher MERV rated filter might be best since it will trap harmful particulates in the air. You may need to change your filter more often with higher MERV-rated filters because restricted airflow can damage the furnace's fan. However, if your chief concern is an efficient furnace, choosing a higher mid-range MERV rating might be more in line with your goals.
Consider the Material
Another important consideration when choosing your filter is the type of material. The most commonly used and inexpensive furnace filters are made of spun fiberglass. These typically have a MERV rating between 1 and 4. Pleated fabric filters made of cotton or polyester sheets are also popular and tend to have higher MERV ratings of between 5 and 16. HEPA filters, or high-efficiency particulate-arresting filters, have the highest MERV ratings between 17 and 20. Finally, there are washable and reusable fabric filters that can last 6 to 8 years and are typically rated between 1 and 4 on the MERV rating scale.
Consider a HEPA filter
If someone in your home suffers from particularly bad allergies or their health is drastically affected by pollution, you might want to consider a HEPA filter, as mentioned previously. HEPA filters are electrostatic, meaning they use an electrical charge to trap particles in the air. This can drastically cut down on harmful particulates. However, because HEPA filters are so thick, you should check with your HVAC maintenance expert to find out if your furnace can handle a HEPA filter before installing one.