What Happens When We Leave Our HVAC Fan On All The Time?

Fan running constantly

As homeowners, we are always looking for ways to save energy and cut down on our utility bills. One common debate is whether to leave the HVAC fan on continuously or only when the air conditioning or heating is running. In this blog post, we will explore the advantages of leaving the HVAC fan on continuously, and why it may be a good idea for your home.

First, let’s define what we mean by the HVAC fan. This refers to the blower fan in your heating, ventilation, and air conditioning (HVAC) system, which is responsible for moving the conditioned air throughout your home. The fan can generally operate in two modes: auto and on. In auto mode, the fan turns on automatically when the heating or cooling system is running, and turns off when the temperature has been reached. In on mode, the fan runs continuously, even when the heating or cooling system is not actively running.

Now let’s dive into the advantages of leaving the HVAC fan on continuously:

  1. Improved Air Quality: When the HVAC fan is left on continuously, it helps to circulate the air throughout your home. This means that air is constantly being filtered and cleaned, removing dust, pet dander, and other allergens from your home’s air supply. This is particularly important for those who suffer from allergies or asthma, as it can help to reduce the presence of allergens in the air.
  2. More Consistent Temperature: Leaving the HVAC fan on continuously can help to maintain a more consistent temperature throughout your home. This is because the fan is constantly circulating air, which helps to distribute the heated or cooled air more evenly. This can help to eliminate hot or cold spots in your home, and ensure that all rooms are comfortable.
  3. Energy Savings: It may seem counterintuitive, but leaving the HVAC fan on continuously can actually help to save energy. This is because the fan uses a relatively small amount of electricity compared to the heating or cooling system. By keeping the fan on, you can help to maintain a more consistent temperature throughout your home, which means that your heating or cooling system doesn’t have to work as hard to maintain the desired temperature. This can help to reduce energy consumption and lower your utility bills.
  4. Reduced Wear and Tear on the System: Finally, leaving the HVAC fan on continuously can help to reduce wear and tear on the heating and cooling system. This is because the fan is constantly circulating air, which helps to keep the system in good working order. When we leave the fan off for long periods of time, it can lead to the buildup of dust and other debris, which can cause the system to work less efficiently and eventually break down.

While there are certainly advantages to leaving the HVAC fan on continuously, it is important to note that there are some potential downsides as well. For example, running the fan continuously can increase noise levels in your home, which may be a concern for some homeowners. In addition, it can lead to increased dust and debris buildup in your HVAC filter, which may require more frequent cleaning/replacement (after a few months, this will likely equal out if you’re using a decent filter).

Overall, whether to leave the HVAC fan on continuously or not is a personal choice that depends on your individual needs and preferences. However, by considering the advantages and potential downsides, you can make an informed decision that is best for your home and your family.

In addition to leaving the HVAC fan on continuously, there are other steps you can take to ensure that your HVAC system is running efficiently and effectively. One of the most important is replacing your HVAC filter religiously. Whether I’m doing air quality testing or home performance tests ( more than an energy audit, but similar), this is the number one problem that I see in homes. PLEASE change your filters! The filter is responsible for trapping dust, dirt, and other particles that can build up in your system and reduce its efficiency. When the filter becomes clogged, it can cause your system to work harder than it needs to, which can increase energy consumption and utility bills.

By replacing the filter regularly, you can ensure that your system is running smoothly and efficiently, and reduce the risk of breakdowns and repairs. Experts recommend replacing your filter at least every three months, or more frequently if you have pets, allergies, or live in a particularly dusty or polluted area. By combining the benefits of leaving the HVAC fan on continuously with regular filter replacement, you can enjoy a comfortable and energy-efficient home all year round.

Unsure what any of this means? Don’t know where to find your filter? Are you scared by the prospect of leaving fans on all the time? Contact us today and we can talk you through it!