The air filters protecting the air quality in your Twin Cities area home might be causing more harm than good. If the filter isn’t up to par, you may be under the impression that your indoor air is clean when it’s actually filled with microscopic pollutants that are making you sick. Regularly replacing, upgrading and inspecting these air filters will help keep your home’s air clean and healthy.
A variety of air filters are available, and range from the cheap filter that probably came with your HVAC equipment to gas-phase ductwork filters and single unit air purification systems. The air filter in your furnace or heat
pump likely can be upgraded to a more efficient model that traps particles and contaminants from re-entering your home’s air. Many homeowners choose to upgrade their HVAC filter instead of purchasing a separate air purification system, with the former course usually being more cost effective.
What to look for in HVAC air filters:
- MERV rating – The Minimum Efficiency Rating Value tells you how well a particular filter captures the smallest particles. Ranging from 1-16 for residential use, the higher numbers capture smaller particles. For a typical home, most experts recommend a filter between 6 and 12, which will provide a good balance between maintaining indoor air quality and proper airflow.
- Pressure drop – Also called filter resistance, this determines what effect the filter has on the HVAC unit’s airflow.
- Arrestance – The filter’s ability to trap tiny dust particles.
- Dust spot efficiency and holding capacity – How well the air filter can remove and hold onto dust particles in the air.
- Efficiency – The filter’s overall ability to remove particles and contaminants.
For all of the preceding values, an HVAC professional can help you decide which levels will be best for your home’s equipment and circumstances.
If you’re looking for a separate air purification system, consider the Air Changes Per Hour (ACH) and the Clean Air Delivery Rate (CADR) of the unit. The ACH measures the how often the unit exchanges the air in your home. For example, if the ACH rating is an 8, it will exchange the air up to eight times every hour. The CADR rating informs the consumer how much and how well the air is purified by the device.
For more information about air filters, please contact us at Marsh Heating & Air Conditioning. We have been servicing the Twin Cities metro area in Minnesota since 1974.
Our goal is to help educate our customers in Minneapolis-St. Paul, Minnesota 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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