Furnace and heat pump filters serve two functions: first, they keep out materials that might damage or obstruct the machines; and second, they screen out small particles that would otherwise enter the air circulation of your house. According to some, the pre-installed filters that come with a furnace are not adequate at performing this second task because they do little to block small particles that can have serious health effects. Others, however, contend that better filters do little to improve indoor air quality because small-particle dust is still stirred up from sources independent of the furnace. If you are concerned about indoor air quality, think about upgrading your filter and changing it regularly. At the very least, it will help your furnace or heat pump efficiency to clean or change the filter regularly.
Tips & Tricks
Read your furnace manual to learn how to change or clean the filter. If you don’t have the manual, check online.
Monitor your filters regularly. Set a maintenance schedule and stick with it: monthly or seasonal changes will help the systems to run efficiently.
Web & Print Resources
Furnace filter overview and maintenance:
About furnaces and heat pumps:
Many of the particles floating in the air are only several microns wide. For comparison, a human hair is about 70 microns in diameter. Source