As an HVAC expert with years of experience, I have been asked countless times about the frequency of changing furnace filters. While the general recommendation from air filter manufacturers and HVAC companies is to change the filter every 90 days or 3 months, there are several factors that can affect this timeline. These include the location of your home, the presence of pets, and the age of your system and equipment. In this article, I will delve deeper into the reasons why it is crucial to regularly change your furnace filter and how often you should do so. For homes with pets, it is recommended to change the filter every 60 days or every 2 months.
If you have multiple pets or people with allergies or respiratory conditions in your home, it is best to change the filter every 20 to 45 days. On the other hand, vacation homes or vacant homes that are not used frequently can wait up to 9 to 12 months before changing the filter. The general rule of thumb is that the more you use your home, the more often you should change your air filter. This applies even during summer months when your furnace may not be in use. If you struggle to remember when to change your filter, a good tip is to do so every time the seasons change. However, it is important to note that these recommendations may vary depending on the type of filter you have.
For instance, experts suggest changing fiberglass filters every 30 days as they are of relatively poor quality. On the other hand, more expensive pleated filters can last up to three to six months before needing replacement. The best way to determine how often your specific filter needs to be changed is by visually inspecting it every month. After a few months, you will have a better idea of how quickly it gets dirty. It is also important to re-evaluate the frequency of changing your filter if you have a new pet or if the outdoor air quality has been poor.
Changing the filter is a simple process that involves loosening the screws that hold the filter cover in place or removing the filter from a slot. Neglecting to change a dirty filter can lead to a buildup of dust, hair, mold, and other debris inside your heating and cooling system. Depending on your lifestyle and the type of filter you have, you may need to change it more often than the recommended guidelines. When it comes to choosing the right filter for your furnace, it is important to consider its MERV (minimum efficiency reporting value) rating. Filters with higher MERV ratings are denser and can be more effective in filtering out smaller particles such as kitchen smoke, smog, and virus carriers.
Even if no one in your household has allergies, it is still advisable to change your filter frequently, especially if you have multiple pets. Every home is unique, so it is possible that you may need to change your filter more often than your neighbor. One common misconception is that high-efficiency filters are designed to filter out small bacterial, mold, and fungal particles. However, standard MERV 8-11 filters are only effective in blocking larger particles of dust, dirt, and hair. The main purpose of an air filter is to trap these contaminants and prevent them from entering your heating and cooling system and ultimately, your lungs.
The MERV rating of a filter indicates how effectively it can do this job. So why is it so important to regularly change your furnace filter? For starters, a dirty filter can make it harder for your furnace to draw in air, causing it to work harder and consume more energy. This can lead to higher energy bills and put unnecessary strain on your system, potentially shortening its lifespan. Additionally, a clogged filter can also affect the air quality in your home, leading to respiratory issues and allergies. As an HVAC expert, I highly recommend following the manufacturer's recommendations for changing your furnace filter. However, it is important to keep in mind that these are just guidelines and may need to be adjusted based on your specific circumstances.
Regularly inspecting your filter and changing it when necessary can help ensure that your heating and cooling system runs efficiently and keeps the air in your home clean and healthy.