Should I Set My Thermostat Fan to "ON" or "AUTO"?

The Short Answer Is: The best thermostat fan setting for your heating and cooling system depends on your comfort preferences and energy efficiency goals. "AUTO" is the more energy-efficient option, as it runs the fan only when heating or cooling is actively needed. "ON" keeps the fan running continuously, which can help with air circulation and filtration but may consume more energy. Choose "AUTO" for energy savings and "ON" if you want constant air circulation or improved air filtration.

Temperatures can soar or plummet depending on the time of year. Throughout the year, it is important to have reliable heating and cooling systems in order to keep your home supplied with cool or warm air. However, it is not just the temperature of the room that can help you beat the heat.

Your thermostat fan setting is equally as important. This decision may seem trivial at first, but it can certainly have a large impact on the comfort and efficiency of your air conditioner, heat pump, or furnace. In this blog, we will explain the two settings – "ON" and "AUTO" – and discuss the benefits of using each one.

What Is the Difference Between "ON" and "AUTO"?

Before we dive into the benefits of each option, let’s first determine what exactly each thermostat setting means. The thermostat fan setting controls the blower motor fan within your heating or cooling system air handler, which is responsible for blowing conditioned air throughout your home as heating or cooling cycles run. You can also use the blower fan outside of heating and air conditioning system operation by adjusting the thermostat setting.

When your thermostat fan is set to “ON,” it means that the fan will run continuously, even if the thermostat reaches your desired temperature setting and the HVAC system is not currently in use. You may notice hot air instead of cool air when the air conditioner is off, and vice versa as the heating system rests.

When the fan is set to “AUTO,” it means that the fan will only run when the air conditioning unit is actively running. This means that the fan will not run when the air conditioning unit has reached the temperature that you have set.

Benefits of the "ON" Setting

There are a few benefits of keeping your thermostat fan on the "ON" setting. One of the biggest benefits is that it helps with air circulation in your home. When the fan runs continuously, it helps to distribute air throughout the house, which can help to create an even temperature throughout the rooms and eliminate hot and cold spots.

Another benefit of keeping the fan running all the time is that it can help provide better air quality. When the AC fan is in "ON" mode and constantly blowing, it enables air filters in the HVAC system to constantly filter the air in your home, removing allergens and impurities that may have been trapped in the air. This can help to improve your overall indoor air quality, which can lead to better health and fewer allergy symptoms.

Disadvantages of the "ON" Fan Setting

Keeping your thermostat fan set to "ON" may seem like a great way to circulate air throughout your home or office, but it actually has some disadvantages.

  • Using this setting does lead to more energy consumption, as the blower's motor runs more frequently - you may notice slightly higher energy bills.

  • You may find that you have a clogged filter sooner that usual if you use the system's fan constantly, as the air filter is constantly working to remove particles from the air supply.

  • It can cause unnecessary wear and tear on the fan's motor, ultimately leading to costly HVAC repairs or premature failure.

Benefits of the "AUTO" Setting

While there are benefits to keeping your thermostat fan on the "ON" setting, there are also advantages to using the "AUTO" setting.

One of the biggest benefits of the "AUTO" setting is that it is the most energy efficient option. Because the fan is not constantly running, it does not use as much energy as it would if it were always on. This means that it can help to reduce your overall energy usage, which will lower your energy costs, decrease monthly energy bills, and help create a more eco-friendly home.

Another advantage to using "AUTO" mode is that it can prolong the life of your heating and air conditioning units. Because the AC fan is not always running, it is not putting as much wear and tear on the unit. This can help to extend the life of the unit and save you money in the long run.

Disadvantages of Using the "AUTO" Setting

When the fan is set to "AUTO", it only turns on when the temperature inside the house falls outside the set temperature range. This means that the air circulates less frequently, which can cause allergens, pollutants, and other particles to accumulate in the air ducts. Additionally, an "AUTO" setting can cause temperature imbalances in the home leading to hot and cold spots.

Which Setting Should You Choose?

When it comes to choosing between the "ON" and "AUTO" settings for your thermostat fan, there is no right or wrong answer. The setting you choose will depend largely on your personal preferences, as well as the specific needs of your home.

If you live in a humid area (like Central Ohio) or if your home is prone to developing hot spots, then you might find that the "ON" setting is more beneficial to your home comfort. Similarly, if you have pets or allergies, then the "ON" setting can help to improve your air quality.

On the other hand, if you are looking to save money on your energy bills or if you want to prolong the life of your HVAC unit, then the "AUTO" setting may be the better option for you.

What's the Best Thermostat Fan Setting?

The decision to choose either the “ON” or “AUTO” setting for your thermostat fan is an important one. There are benefits to both settings, and the choice you make will depend on your unique needs. If you are still unsure which setting is right for you, consider speaking with a professional HVAC technician at Buckeye who can provide guidance and expert advice.

Our expert technicians are knowledgeable in all aspects of heating and cooling systems, including thermostat settings and blower fan repairs. With our help, you can easily choose the best thermostat fan setting for your specific needs, whether you need to conserve energy or improve comfort in your home.

If you're experiencing issues with your blower fan, don't hesitate to give us a call to schedule prompt repairs. Trust Buckeye to keep your Columbus heating and air conditioning system running smoothly and efficiently. Contact us today to schedule your service appointment.

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