As the weather starts to cool off, you may be wondering about how you’ll prepare your heating and cooling. After all, HVAC costs can add up to a significant portion of your monthly electric bill. To learn new ways to reduce costs, some owners look closer at their thermostat. Maybe there’s a setting they could use to improve efficiency?
The majority of thermostats come with a ‘Fan’ or ‘Fan On’ setting. But if the fan is on during a regular cycle, what does the fan setting offer for the HVAC system? This guide should help. We’ll walk through precisely what the fan setting is and whether 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 will generate heat at a low level in this setting, but in general heating or cooling isn’t being produced. The ‘Auto’ setting, conversely, will start the fan during a heating or cooling cycle and switch it off after the cycle is over.
There are pros and cons to switching on the fan setting on your thermostat, and the ideal option can depend on your unique comfort requirements.
Advantages to using the Fan/On setting:
- You can keep the temperature throughout your home more consistent by permitting the fan to keep circulating air.
- Indoor air quality can increase as steady airflow will keep passing airborne contaminants through the air filter.
- Fewer start-stop cycles for the system's fan helps extend its life span. Since the air handler is typically a component of the furnace, this means you might minimize the risk of needing furnace repair.
Disadvantages to utilizing the Fan/On setting:
- A constant fan can raise your energy bills somewhat.
- Nonstop airflow could 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
Through the summer, warm air will sometimes linger in unfinished spaces like the attic or an attached garage. If you leave the fan on, 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 set temperature. In extreme heat, this can lead to needing AC repair more often as wear and tear grows.
The reverse can occur in the winter. Cooler spaces such as a basement will hold onto cooler air, which will eventually drift 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 remain 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 will vary. Leaving the HVAC system’s fan on may be best for you if:
Someone in your household suffers from allergies. Allergies and other respiratory conditions can be stressful on the family. Leaving the fan on should help to increase 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 should help lessen these changes by constantly refreshing each room’s supply of air.