As the weather starts to cool off, you may be concerned about how you’ll take full advantage of your heating and cooling. After all, HVAC costs can contribute a big piece of your monthly electric bill. To learn new ways to save, some people look closely at their thermostat. Is there a setting they could use to improve efficiency?
The bulk of thermostats have a ‘Fan’ or ‘Fan On’ setting. But if the fan is going during a regular cycle, what can the fan setting provide for the HVAC system? This guide should help. We’ll review just what the fan setting is and how you can use it to save money over the summer or winter.
What Is the Fan Setting on My Thermostat?
For most thermostats, the fan setting means that the air handler’s blower fan stays on. Some furnaces may continue to operate at a low level with this setting, but for the most part heating or cooling isn’t being made. The ‘Auto’ setting, conversely, will start the fan through a heating or cooling cycle and turn it off when the cycle is complete.
There are pros and cons to switching on the fan setting on your thermostat, and what's ideal will depend on your unique comfort needs.
Advantages to trying the Fan/On setting:
- You can keep the temperature in each room more balanced by allowing the fan to keep running.
- Indoor air quality should improve since continuous airflow will keep forcing airborne pollutants into the air filter.
- A smaller number of start-stop cycles for the system's fan helps expand its life span. Since the air handler is typically connected to the furnace, this means you might minimize the risk of needing furnace repair.
Drawbacks to using the Fan/On setting:
- A continuous fan will likely raise your energy bills somewhat.
- Nonstop airflow may clog your air filter soon, increasing the frequency you should replace it.
Should My Thermostat Be on Fan or Auto in Summer/Winter
In the summer, warm air can linger in unfinished spaces like the attic or an attached garage. If you use the fan setting, your HVAC system can pull this warm air into the rest of your home, forcing the HVAC system to run longer to preserve the set temperature. In extreme heat, this could result in needing AC repair more regularly as wear and tear gets worse.
The opposite can happen during the winter. Cooler spaces such as a basement will hold onto cooler air, which can eventually make its way into the rest of your home. Leaving the fan setting on may pump more cold air upward, increasing the amount of heating you need to remain warm.
If you’re still trying to decide 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 has allergies. Allergies and similar respiratory conditions can be tough on the family. Leaving the fan on is more likely to enhance indoor air quality, helping your family breathe easier.
Your home has hot and cold spots. All kinds of homes deal with stubborn hot and cold spots that quickly evolve to a temperature different from the rest of the house. The fan setting might help lessen these changes by constantly refreshing each room’s ventilation.