When you are standing at the home improvement store, we know how overwhelming it can be to choose the right air filter. How do you know which is the best to purchase? You don’t want to simply pick the air filter that fits your return air duct. Other considerations include the air filter’s efficiency (which affects your energy bills), your family’s health needs and the air quality you want in your home.
An air filter’s job is to remove pollutants, like dust, dirt and pet dander from your home’s indoor air. You can know how effective an air filter will be by reviewing its Minimum Efficiency Reporting Value (MERV) rating. Ratings range from 1 (the lowest filtration possible) to 20 (the highest filtration possible). Simply put, the higher the MERV rating on an air filter, the fewer dust particles and contaminants that can pass through it and vice versa. Learn more about MERV ratings.
You might think high efficiency air filters are the way to go then. However, they can work so well sometimes that they cause your HVAC system to be less efficient because they block too much airflow. This leads to higher energy bills and could damage your furnace if it overheats.
So what is the best air filter for your home? One that removes the most airborne pollutants but enables your HVAC system to do its job without strain.
Let’s break down the four main types of air filters, including the advantages and disadvantages of each:
- Fiberglass air filters
- Most common type
Usually the lowest MERV rating, between 1 and 4
Traps large dust particles but not mold, pollen or smaller particles
Best to replace every 30 days
- Protects your HVAC equipment but doesn’t help improve indoor air quality
- Polyester and pleated air filters
- Similar to fiberglass filters but has a higher resistance to airflow to stop dust better
- Costs more than fiberglass air filters but also last longer
- More pleats means air can pass through more easily
- Less efficient than HEPA filters at trapping smaller particles
- MERV ratings between 5-13 (the United States Environmental Protection Agency (EPA) says air filters with a MERV rating between 7 and 13 can be nearly as effective as true HEPA filters)
- High-efficiency particulate arrestance (HEPA) air filters
- Filters air at a very fine scale, removing up to 99.97 percent of airborne particles to sanitize the air the best
- Especially helpful for people with asthma or allergies
MERV ratings between 17-20
More expensive but also last for about six months
Must meet specific guidelines by the U.S. Department of Energy (DOE) to be labeled a HEPA filter
Often used in hospitals and vacuum cleaners
Too large or restrictive of airflow for most residential HVAC systems, requiring an HVAC company to retrofit your furnace
- Washable air filters
- Requires maintenance but reusable if cleaned well about every 90 days
- Must make sure they are fully dry before putting back into your system, or mold and bacteria can grow
- More environmentally-friendly than disposable filters but also more expensive
- MERV ratings usually between 1 and 4
Stiles Heating & Cooling can help you weigh all your options when it comes to choosing the right type of air filter for your budget, your family’s health and your home’s air quality. Call us today!