Your air filter is one of the smallest, simplest, and yet most crucially important pieces to your home’s heating and air conditioning system. However, despite it having such an important part to play in how your home functions, many people don’t pay enough attention to it or change it out nearly often enough. When the time comes to replace your filter, knowing what to look for in order to buy the right one for your home isn’t always as simple or straightforward as it might seem. There are several things you need to keep in mind in order to make an educated purchasing decision. So to help you make the right choice, here are a few things to be mindful of when selecting a replacement air filter.
MERV Rating
Filters are graded for their ability to remove contaminants from the air using a system known as a Minimum Efficiency Reporting Value rating, or MERV rating for short. Generally, lower MERV ratings are cheaper but filter out less and higher ratings are more expensive but do a better job actually cleaning the air.
While you might be tempted to think that a higher MERV rating is always better, you need to consider your HVAC system and your needs first. If your air conditioner is designed to work with filters that have a MERV rating between eight and 12, a higher number will restrict the airflow to the system, starving it of air which places extra strain on your blower motor and heating/cooling coils. This can dramatically shorten your system’s lifespan and lead to higher energy bills from reduced efficiency. Furthermore, most homes don’t actually need a filter designed to service hospital clean-rooms designed for quarantining high-risk patients. Even those with severe allergies or asthma are usually perfectly comfortable and at a minimal risk with a MERV rating of 12 to 14.
Filter Design
Thickness, pleats, and material are all important factors for a filter. In general, a thinner filter will need to be changed out more often because it has less surface area for air to pass through and be filtered. A thicker filter generally has more area, and thus can last longer. Pleats are another factor that has to do with surface area: more pleats means more exposed spots that air can enter the filter through, and thus more area that can fill up with dust before it needs replaced. A thicker pleated filter goes even further and adds a greater amount of depth.
Finally, the material a filter is made out of will also influence how well it works. Generally, fiberglass and other thin material filters are designed to simply protect your filter, not so much to remove contaminants. Paper or cloth filters tend to do this better and will remove microscopic contaminants, but they cost quite a bit more than a fiberglass filter.
The best place to start when looking for a new air filter is to consult the owner’s manual on your heating and air conditioning system to find out what they say your system is rated to handle. If you need slightly better filtration or are dealing with poor indoor air quality, you may want to consider upping your MERV rating by one to two levels at the absolute maximum, and be mindful of your system to make sure it doesn’t suffer serious negative ramifications as a result.
You should also schedule a tune-up and maintenance service with a Sterling heating and air conditioning repair professional from Donmar Heating, Cooling & Plumbing.
Call us today at (703) 457-8676 to schedule an appointment and learn how these services can help keep your system working in peak condition!