How effective is the air filter in your home? If you are like most people, you do not often think about the air filter for your HVAC system, but it is one of the most important elements of the system. It ensures there is no dust or particulates that get into the system and cause damage, and it helps to keep the air quality in the home cleaner and easier to breathe. The filters all have a MERV rating (Minimum Efficiency Reporting Value), which can be used to provide you with an understanding of what filter you need for your system.
They range from MERV 1 to MERV 20, but for most homes that do not want to undergo any alterations to their HVAC system, air filters will be rated from MERV filter 1 through MERV 14. The higher the rating the smaller the particulates it can keep out. However, this does not always mean that higher is better for your home.
Why Does Higher Not Always Mean Better?
When the MERV rating is higher, it means that the pores in the filter are smaller. This keeps out certain levels of particulates, but it also means that the air flow will be reduced. This will end up causing greater resistance in the HVAC system, which means it is not going to be as efficient. In fact, it could cause more problems with the air quality in the residence and put more pressure on the fans to try to keep pushing air through.
You always need to consider the system that you have in place and then choose the MERV filter that is the highest rated that will still provide the correct amount of airflow through the system.
One of the other things that you will want to note about the MERV filters that have higher ratings is that they will need to be changed quite often. This is because they tend to gather a lot of particulates. You will want to change these out every three to four months or so. If you wait too long, the airflow is going to be restricted even further.
Even though you will need to change the filters often, it is still more cost-effective than waiting until the filter is so clogged that it causes a problem with the system that will need to have expensive repairs.
MERV Ratings for Most Homes
When you are choosing your MERV filter, you need to consider the size of the filter to make sure it will fit with your system, and you want to be sure you have the right rating for your residence. As mentioned, with a typical residence, the filters you will be using will have MERV ratings that are from 1 to 13.
Those that are on the lowest end of the scale, MERV 1 to MERV 6, will not do much to help with the air quality in the home. They are generally only used for window AC units, and you will often find these in apartments and condominiums. Those who want to have a better rating and better air quality for their home may want to choose a MERV 7 through MERV 11 filter. These are often pleated rather than flat, and they can trap more particulates. They tend to be a good option for many homes, as long as there are not furry pets or those who have respiratory issues. The typical highest level of home MERV filters will be from 9 to 13. These can trap small particles, provide clean air, and they will work with most of the HVAC systems that are already in place.
Remember, just because the MERV filter rating is higher does not mean it is the right choice. Find the filter that works the best for your system and still provides airflow.