Air Filter Efficiency: Low or High?
How Do You Know Which Is Best?
Air filter efficiency makes a big difference in your HVAC system’s performance. The cleaner the air going into the system, the better the air quality going back into your home. Dust and other particles that infiltrate the system can cause increased fuel consumption, damage and costly repairs. Believe it or not, though, the highest rated air filter might not be the best one for your HVAC system.
Air filter quality is measured by MERV, or Minimum Efficiency Rating Value, with one being the lowest and 16 the highest rating. Newer, high efficiency home HVAC systems work well with filters rated an 11 MERV, while older ones will likely do better with an 8 MERV. That is because the higher the rating, the more dense the filter, allowing it to collect miniscule airborne particles. It requires a higher performance motor so that the system is not overburdened. You should check with your HVAC technician for the right air filter for your system.
Oddly enough, low quality filters can actually do pretty well for a limited time. While they initially only catch larger airborne particles, once the filter gets clogged, smaller particles are caught too. There comes a point, though, when the burden on the system trying to get air through the filter can begin to damage the motor, far outweighing the cost of regularly replacing an inexpensive filter.
How often you need to change your air filter depends on the type of system you have, whether there are pets in the home and if your area has more dust and pollens. Most MERV-rated air filters suggest changing every 90 days, but it is a good idea to check the filter once a month and change it when it becomes dirty. Higher-efficiency filters collect many more particles and will likely need more frequent changes. Again, your HVAC technician can assist you with a schedule that benefits both your system and your wallet.
For more information on this and other HVAC needs, contact the comfort consultants at Gulf Coast Air Systems. We have served the Tampa Bay area for more than three decades.