The air filter in your furnace or heat pump serves two important purposes. First, it allows your HVAC system to operate efficiently and smoothly, while extending the life of your heating equipment. It does this by preventing dust and other particles from clogging up your equipment, making it work harder to keep you comfortable and resulting in higher energy bills and repair costs. Secondly, your furnace filter improves the air quality in your home, trapping impurities such as dust, mold, bacteria and viruses that can make you sick. Inspecting your filter every month, and changing it when it gets dirty, is the best way to keep your furnace running efficiently all season long while helping to keep your family healthy.
How to choose a filter
When stocking up on filters, use the Minimum Efficiency Reporting Value, or MERV, rating to help you choose the right filter for your system. Residential filters are rated between 1 and 16, with higher ratings translating to higher-efficiency filters. In this context, high efficiency translates into the ability to capture the smallest particles. Here’s a rough guide to the ratings:
- MERV 1-4 filters trap particles larger than 10 microns and do little to improve your indoor air quality. However, if all you’re concerned about is maintaining system airflow and you plan to change the filter regularly, these usually will be adequate.
- MERV 5-8 filters trap particles between 3 and 10 microns in size and are suitable for most residential needs.
- MERV 9-12 filters trap particles as small as 1 micron in size and will benefit those who suffer from allergies and asthma.
- MERV 13-16 filters trap particles as small as .03 microns in size and are generally used in commercial buildings.
Check the specs of your furnace before upgrading your filter. Some systems won’t work with higher MERV filters, which can actually impede the flow of air due to their thicker, denser construction. When choosing a filter, it’s always important to strike a balance between optimum air flow and indoor air quality.
How to change your filter
Most air filters are located in the blower compartment between your furnace and the air intake. Slide out the old filter and insert the new one with the arrows on the frame pointing toward the furnace.
Paschal Heat, Air & Geothermal has been serving Northwest Arkansas with honesty and integrity for over 40 years. For advice on choosing the best air filter for your system, please feel free to contact us.
Our goal is to help educate our customers in Northwest Arkansas about energy and home comfort issues (specific to HVAC systems). For more information about air filters and other HVAC topics, download our free Home Comfort Resource guide.
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