What Is An Air Conditioner/Furnace Filter?

An air conditioner filter is just that, a filter for your air conditioner and sometimes your furnace as well. The goal of this filter is to provide your home with clean high quality air. Along with that, the filter also serves a purpose by keeping your air conditioner and your furnace clean. The filter traps the dust, pollen, and any other debris that would otherwise be circulated through your system and your home.

Not only do they keep dust out of your home but they also keep dust off of the evaporator coils. The evaporator coils is where your cold air comes from. (In most cases the evaporator coil sits directly above your furnace inside your home.) If the coils are covered in dust and grime then the performance of your system is going to go down. You may also inadvertently damage the evaporator if you operate without a filter or with a very old filter. The more dust and grime that gets on your evaporator the less capable it is at removing heat. Some folks have their evaporator coils checked and cleaned each year as well as changing their filters regularly.

Not changing the filter can have effects on the performance of your air conditioner as well as longevity of your system. In some cases a dirty air filter can take away ten to fifteen percent system efficiency. This will end up costing you more money on your energy bills and could also end up costing you a whole lot if something fails in your air conditioner due to a clogged filter. A dirty filter can also affect the air quality within your home and could lead to problems for those in your family who suffer from asthma or other allergies. My father for example has severe asthma and they have religiously changed their filter every thirty days to prevent flare ups. He is especially sensitive to pet hair and by changing the filter religiously as well as buying a higher quality filter we are able to minimize any symptoms.


Your air conditioner and your furnace are some of the most expensive appliances in your home. It only makes sense to take care of them and to ensure that they last as long as they can. In today’s world a new AC and furnace could cost anywhere between six to twelve-thousand dollars.

By ensuring that your air conditioner filter is taken care of every few months you not only protect your system and investment but it also provides you clean air throughout your home. If you aren’t already, please take the time to clean or replace air filters not only for your health but also for your wallet!