While there are many reasons to change HVAC air filters regularly – such as lowering utility bills and lessening the strain on HVAC equipment – one primary reason is to enjoy cleaner indoor air. You should plan to change the filter every one to three months in your furnace, heat pump or air conditioner, depending on the season.
Apart from changing the filter regularly, you also need to find the right type of filter for your home. Most filters are designed to trap large particles without a problem. Large particles trapped by nearly all media air filters include:
- Pollen
- Dust
- Dust mite allergens
- Animal dander
- Some types of mold spores
There are millions of other smaller particles floating around inside your home that low-efficiency filters simply can’t trap. Here’s a look at the minimum efficiency reporting value (MERV) scale and the capabilities of filters in each range along the scale to help you choose the right air filters for your HVAC system:
- MERV 1-4: Flat or panel air filters belong to this category. These come standard on furnace and air conditioners to protect the equipment from unwanted dust or debris. However, they are unable to capture smaller particles that can contribute to allergies and illness.
- MERV 5-13: These medium-efficiency pleated air filters are more costly than flat or panel air filters, but they are much better at capturing smaller particles, such as bacteria, viruses and a greater number of pet allergens. They’re still relatively inexpensive when you consider the great improvement in air cleaning.
- MERV 14-16: High-efficiency extended surface filters are the best at trapping the smallest particles in the air. However, installing one on your HVAC equipment may restrict airflow in your HVAC system, which is really something you want to avoid. Boosting the fan speed may be enough to overcome this, but your energy bills will increase due to the modification. Your trusted HVAC professional can give you good advice on whether these filters are right for your system.
Medium-efficiency pleated air filters are often the best choice for HVAC applications because they provide the ideal balance between efficient heating and cooling equipment operation, purchase price and indoor air quality. For more tips on choosing and replacing HVAC air filters in your Twin Cities metro area home, please contact us at Marsh Heating & Air Conditioning.
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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