If you have a home or other building that contains a forced-air heating system, you probably try to periodically change the filter it uses. Filters are intended to be changed regularly, but how often is that? Complicating the issue is the variety of filters on the market. There are the traditional fiberglass filters, that you can find for sale in many stores for just a few dollars, but there are plenty of other options out there – many of them more expensive.

What is a Filter For?

For starters, the filter in your heating system actually has two purposes. The first is to protect your HVAC equipment and keep it running properly by keeping dust and debris out of the machinery. If the inside of your furnace gets clogged with dust, it will have to work harder – and less efficiently. The second purpose of a filter is to improve indoor air quality. A good quality filter can screen out extremely fine particles including bacteria, allergens, and molds. People with allergy problems can benefit from the improved indoor air quality that results from high-quality filters, especially those that are HEPA quality. And there are even reusable filters, not unlike dryer filters, that can be washed then reused for years.

Choose the Filter That’s Right for You

Pulling an HVAC filter out of a furnace. When choosing a filter, there are several things to consider. First is the actual furnace in your home. Some older models are simply not equipped to use a high-quality filter. That’s because these filters are not a single sheet, but made up of multiple pleats. Older furnaces simply do not have the power to pull the air through this thicker filter. For an older furnace, you are better off sticking with the standard filter, which you can change every one to three months. Another issue to consider is a lifestyle. Smokers, pets, even children can add to the dust in your home. While you might think that a more expensive filter is warranted for these conditions, in fact, it may not be much help. Filters can pick up harmful air particles that actually happen to enter the unit, but they can’t do much about particles that exist in the home and that don’t come into contact with the unit. A filter can only improve air quality if the unit is run continuously, so using an expensive one is always worth the effort. However, if you have allergies, asthma or other health concerns, a good quality filter is a worthwhile investment. Here is a great chart categorizing filters by their MERV (minimum efficiency reporting value) rating.

Talk to an HVAC Pro

Still, confused about which filter is right for your home? October is a great time for a furnace check-up and cleaning. Make sure to ask your HVAC tech which is the right filter for your furnace and lifestyle. It may improve your air, save on energy bills and help your furnace keep running efficiently for years to come.