As an HVAC expert, I am often asked about the frequency of changing air filters. The truth is, there is no one-size-fits-all answer. The types of air conditioning filters used in your home, as well as other factors, can affect how often you should replace them. In this article, I will provide you with some general guidelines and tips to help you determine the best replacement schedule for your air filters.If you use standard 1- to 3-inch air filters, it is recommended to change them every 30 to 60 days if you do not have allergies.
However, if you or someone in your household has mild or moderate allergies, it is best to change the filters more frequently, approximately every three weeks. This is because the air filter plays a crucial role in removing allergens and other irritants from the air, and a dirty filter can worsen allergy symptoms. In general, most air filter manufacturers and HVAC companies recommend changing the air filter every 90 days or every 3 months. However, this can vary depending on certain factors such as the location of your home (e.g. dry and dusty climates), the presence of pets, and the age of your system and equipment. If you have pets at home, it is important to consider changing the filter every 60 days or every 2 months.
In homes with multiple pets or people with allergies or respiratory conditions, it is recommended to change the filter every 20 to 45 days. On the other hand, vacation homes or empty homes that are not used frequently may only need to change filters every 9 to 12 months. The general consensus is that the more you use your home, the more frequently you will need to change your air filter. However, the best way to determine the ideal replacement schedule is to visually inspect the filter every month. After a few months, you will have a better idea of how quickly it gets dirty and when it needs to be replaced.
It is also important to re-evaluate if you have a new pet or if the outdoor air quality has been poor. For basic 1 to 3 air filters, most brands recommend changing them every 30 to 90 days. However, if someone in your family has mild to moderate allergies, it is advisable to use a better quality air filter or change it even more often. Ideally, you should change your air filter every three months; however, there are certain factors to consider when deciding when to replace an old filter. If the dirty air filter is completely covered with dust and dirt, it is a good idea to change it even if it has not reached the end of its recommended lifespan. In fact, using an air filter with a MERV rating higher than what is recommended by the boiler or air conditioner manufacturer can affect its performance.
These air filters act as barriers to prevent contaminants from entering the HVAC system or circulating through the air. Outdoor air quality can also have a significant impact on how often the air filter gets dirty and needs to be changed. For instance, during periods of high pollution or wildfires, it may be necessary to replace the filter more frequently. Therefore, it is important to consider all these factors when determining a replacement schedule and choosing the right type and quality of filter for your home. As an HVAC technician, I often hear homeowners complain about their technician lecturing them on changing their air filter. However, it is crucial to understand that air filters play a vital role in keeping your home's air clean and fresh.
They trap pet hair, dust, and other irritating particles, preventing them from entering your home's HVAC system. The lifespan and replacement cycle of the furnace filter and air conditioner are also affected by outdoor and indoor air quality. For example, after a period of smoke-filled days or poor outdoor air quality, it is important to inspect the air filter and replace it if necessary. Additionally, if you have young children at home, it is recommended to use high-quality pleated air filters and change them as often as every two months.