When the weather starts to cool off, you might be concerned about how you’ll take full advantage of your heating and cooling. After all, HVAC expenses frequently add up to a big piece of your monthly electric bill. To learn new ways to save, some owners look closely at their thermostat. Could there be a setting they can use to improve efficiency?
The majority of thermostats have a ‘Fan’ or ‘Fan On’ setting. But if the fan is running during a regular cycle, what does the fan setting offer for your HVAC system? This guide will help. We’ll walk through precisely what the fan setting is and whether you can use it to reduce costs in the summer or winter.
What Is the Fan Setting on My Thermostat?
For the bulk of thermostats, the fan setting means that the system's blower fan stays on. Certain furnaces will generate heat at a low level in this setting, but for the most part heating or cooling isn’t being generated. The ‘Auto’ setting, conversely, will turn on the fan over a heating or cooling cycle and shut it off after the cycle is finished.
There are advantages and disadvantages to using the fan setting on your thermostat, and the ideal option will depend on your unique comfort needs.
Advantages to switching to the Fan/On setting:
- You can keep the temperature throughout your home more balanced by allowing the fan to keep circulating air.
- Indoor air quality should improve since continuous airflow will keep passing airborne particles into the air filter.
- A smaller number of start-stop cycles for the system's fan helps expand its life span. As the air handler is often connected to the furnace, this means you could minimize the risk of needing furnace repair.
Disadvantages to using the Fan/On setting:
- A constant fan will likely add to your energy bills somewhat.
- Continuous airflow can clog your air filter up more quickly, increasing the frequency you’ll need to replace it.
Should My Thermostat Be on Fan or Auto in Summer/Winter
In the summer, warm air can persist in unfinished spaces such as the attic or an attached garage. If you keep the fan running, your HVAC system might pull this warm air into the rest of your home, forcing the HVAC system to work harder to maintain the desired temperature. In serious heat, this could result in needing AC repair more often as wear and tear grows.
The reverse can take place in the winter. Cooler spaces like a basement will hold onto cooler air, which may eventually drift into the rest of your home. Keeping the fan on will sometimes draw more cold air upward, increasing the amount of heating you need to stay warm.
If you’re still trying to figure out if you should try the fan/on setting, keep in mind that every home and family’s comfort needs are different. Leaving the HVAC system’s fan on could be best for you if:
Someone in your household suffers from allergies. Allergies and other respiratory conditions can be hard on the family. Leaving the fan on should help to improve indoor air quality, helping your family breathe easier.
Your home has hot and cold spots. Many homes deal with stubborn hot and cold spots that quickly evolve to a temperature different from the rest of the house. The fan setting can help lessen these changes by constantly refreshing each room’s supply of air.