You know you need to replace your air filter for your air conditioner, but how do you know which ones to buy? Here are a few tips to help you.
Start with the Size
Your existing filter should be clearly marked with the size; write this down to refer to when actually purchasing the filter you’ve decided on. It’s important that the filter fit snugly. If it’s smaller than the opening, unfiltered air can flow unimpeded through your system, and eventually damage it.
Thickness of the filter matters, too. Filters can vary in thickness from 1-4 inches. Check the owner’s manual for the recommended thickness, as a too-thick filter can restrict airflow and strain your system.
Know Your Needs
The filter will remove small particles from the air before it’s cooled and returned to circulation. If you suffer from allergies, you’ll need a filter that removes the smallest particles possible from the air you breathe. If allergies aren’t a problem, or if you’re on a tight budget, filters that are less efficient cost less and are more readily available. And, if your allergies are seasonal, you can save money by switching to a less expensive filter after your allergy season passes. Air filters are rated for their effeciency, so…
Know Your Ratings
Air conditioning filters are rated on their ability to filter different sizes of airborne particles. This “minimum efficiency reporting value” or MERV, which rates filters from MERV 1 to MERV 12, tells you the relative number of particles that will be trapped in the filter. The higher the rating, the more particles are trapped, and the better the filter is at removing small particles.
Know Your Filters
The most inexpensive filters are made of woven fiberglass or other material, and with a low MERV rating (1 or 2) aren’t very good at filtering allergens from the air. They do very little (removing less than 10% of pollutants) to actually clean the air, but they do protect your heating and cooling equipment from dirt/debris buildup.
Note: You may be tempted to try to extend the life of these filters by cleaning them, but that removes the adhesive coating used to capture particles, and reduces their efficiency even further.
A pleated fabric air filter has much more filter surface area, and removes up to 45% of the pollutants in your home, but at $10 or more each, they are more expensive. The more pleats on the filter, the higher the efficiency, with a MERV 11 or 12 rating. These filters are often sold as being effective at reducing airborne allergens within the home. Air conditioning filters should be changed every few months, or per the manufacturer’s recommendations, in order to keep them working properly.
The most expensive filters are high-efficiency (MERV Rating 14-16) and are often the best filters for a residential air conditioning unit since they remove the most air pollutants (up to 85%), tapping even the tiniest pollutants – even bacteria. However, they are costly at around $20 to $25.
Buy with Confidence
Following these tips and understanding the options available, you can purchase an air conditioner filter with confidence. Remember, no matter what filter you choose, you should always follow the instructions for your particular filter for cleaning and replacement to ensure the efficient performance of your air conditioning system.