Furnace efficiency is an important consideration, especially as winter rolls around, and you find yourself using your furnace more and more. But just as important as furnace efficiency is the efficiency of the filters that you put in your furnace. A number of different types of filters are on the market today, and you can quickly assess their effectiveness by checking their MERV (Minimum Efficiency Rating Value) ratings.
Why are filters important?
Furnace filters keep the air that you breathe indoors clean and healthy by screening a wide range of particles from the air, including dirt, dust, mold spores, insect waste, pollen, pet dander, viruses, tobacco smoke and carpet fibers.
What are MERV ratings?
MERV is a measure of a filter’s effectiveness when it comes to trapping particles from the air. Filters are given a MERV rating on a scale of 1 to 16, measured in microns. Higher ratings mean filters are more efficient and can trap smaller particles.
Types of filters
The standard, disposable fiberglass filters that many furnaces use are unfortunately the least effective, with MERV ratings typically between 1 and 4. Pleated filters are more effective, but they also are more expensive, and you must change them frequently because the particles they accumulate can block air flow.
High efficiency pleated filters are better still. They use an electrostatic charge to help trap particles, and can have MERV ratings up to 11. Rigid cell filters and High Efficiency Particulate Air (HEPA) filters are highly efficient, and can have MERV ratings up to 16, but they are also considerably more expensive than lower-rated filters.
Considerations
Regardless of a filter’s MERV rating, it must be cleaned or changed regularly to maintain its efficiency. You should check your filters every month — just looking at them often tells you whether they’re clean. If there is lots of trapped hair and dust, change them. If it’s hard to tell whether they’re clean, run your finger over them, or take them out and hold them up to a bright light. Additionally, check the manufacturer’s packaging. It should indicate how often the manufacturer recommends changing the filters.
For more information on furnaces, furnace filters and MERV ratings, contact Marsh Heating & Air Conditioning. We have been taking care of the Twin Cities’ HVAC (heating, ventilation and air conditioning) needs since 1974, and our certified technicians can help you keep your heating and cooling equipment running smoothly and efficiently all year long.
Our goal is to help educate our customers about energy and home comfort issues (specific to HVAC systems). For more information about furnace filters and other HVAC topics, download our free Home Comfort Resource guide.
Marsh Heating and Air Conditioning services Minnesota’s Twin Cities. Visit our website to see our special offers and get started today!