Once the weather begins to cool off, you are probably concerned about how you’ll take full advantage of your heating and cooling. After all, HVAC bills can contribute a significant piece of your monthly electric bill. To figure out new ways to lower their HVAC bill, some owners look closer at their thermostat. Is there a setting they can use to increase efficiency?
The bulk of thermostats include both a ‘Fan’ or ‘Fan On’ setting. But if the fan is going during a regular cycle, what can the fan setting provide for an HVAC system? This guide will help. We’ll walk through what exactly the fan setting is and how you can use it to save money during the summer or winter.
What Is the Fan Setting on My Thermostat?
For the bulk of thermostats, the fan setting indicates that the air handler’s blower fan remains on. A few furnaces can run at a low level in this setting, but in general heating or cooling isn’t being generated. The ‘Auto’ setting, in contrast, will run the fan through a heating or cooling cycle and switch it off after the cycle is finished.
There are pros and cons to using the fan setting on your thermostat, and what's ideal should depend on your personal comfort requirements.
Advantages to utilizing the Fan/On setting:
- You can keep the temperature in each room more balanced by enabling the fan to keep generating airflow.
- Indoor air quality can increase as constant airflow will keep forcing airborne contaminants into the air filter.
- A smaller number of start-stop cycles for the HVAC fan helps expand its life span. As the air handler is usually connected to the furnace, this means you could avoid needing furnace repair.
Drawbacks to switching to the Fan/On setting:
- A nonstop fan will likely raise your energy bills by a small margin.
- Nonstop airflow may clog your air filter in a shorter amount of time, increasing the frequency you will want to replace it.
Should My Thermostat Be on Fan or Auto in Summer/Winter
During the summer, warm air will sometimes stick around in unfinished spaces like the attic or an attached garage. If you use the fan setting, your HVAC system may gradually move this warm air into the rest of your home, compelling the HVAC system to work harder to preserve the preferred temperature. In severe heat, this could result in needing AC repair more quickly as wear and tear grows.
The opposite can happen in the winter. Cooler spaces such as a basement will hold onto cooler air, which will eventually make its way into the rest of your home. Keeping the fan on will sometimes pump more cold air upward, increasing the amount of heating you need to stay warm.
If you’re still trying to determine if you should try the fan/on setting, remember that every home and family’s comfort needs are not the same. Leaving the HVAC system’s fan on might work for you if:
Someone in your household deals with allergies. Allergies and similar respiratory conditions can be stressful on the family. Leaving the fan on can help to increase indoor air quality, helping your family breathe easier.
Your home deals with hot and cold spots. All kinds of homes wrestle with difficult hot and cold spots that quickly return to a temperature different from the rest of the house. The fan setting should help lessen these changes by constantly refreshing each room’s supply of air.