When the weather starts to cool off, you might be thinking about how you’ll make the most of your heating and cooling. After all, HVAC expenses can make up a significant chunk of your monthly electric bill. To try and find ways to save, some homeowners take a closer look at their thermostat. Could there be a setting they should use to improve efficiency?
The bulk of thermostats have a ‘Fan’ or ‘Fan On’ setting. But if the fan is running during a regular cycle, what will the fan setting provide for your HVAC system? This guide will help. We’ll review precisely what the fan setting is and whether 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 signifies that the HVAC blower fan remains on. Certain furnaces may continue to operate at a low level with this setting, but in general heating or cooling isn’t being generated. The ‘Auto’ setting, conversely, will turn on the fan through a heating or cooling cycle and switch it off after the cycle is complete.
There are benefits and drawbacks to switching on the fan setting on your thermostat, and the ideal option can depend on your unique comfort needs.
Advantages to using the Fan/On setting:
- You can keep the temperature in each room more uniform by enabling the fan to keep generating airflow.
- Indoor air quality can increase because steady airflow will keep passing airborne contaminants into the air filter.
- A smaller amount of start-stop cycles for the system's fan helps extend its life span. Because the air handler is often a component of the furnace, this means you might minimize the risk of needing furnace repair.
Disadvantages to switching to the Fan/On setting:
- A nonstop fan will likely add to your energy bills somewhat.
- Continuous 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 can linger in unfinished spaces like the attic or an attached garage. If you keep the fan running, your HVAC system may pull this warm air into the rest of your home, forcing the HVAC system to work more to preserve the desired temperature. In severe heat, this may result in needing AC repair more often as wear and tear gets worse.
The reverse can happen over the winter. Cooler spaces like a basement will hold onto cooler air, which can eventually make its way into the rest of your home. Leaving the fan running may pump more cold air upward, increasing the amount of heating you need to keep warm.
If you’re still trying to determine if you should switch to the fan/on setting, remember 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 similar respiratory conditions can be tough on the family. Leaving the fan on can help to improve indoor air quality, helping your family breathe easier.
Your home deals with hot and cold spots. Lots of homes wrestle with stubborn hot and cold spots that quickly shift to a temperature different from the rest of the house. The fan setting might help limit these changes by constantly refreshing each room’s supply of air.