When the weather is cooling off, you are probably wondering about how you’ll take full advantage of your heating and cooling. After all, HVAC costs can make up a significant portion of your monthly electric bill. To try and find ways to lower their HVAC bill, some people look closely at their thermostat. Is there 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 normal cycle, what does the fan setting offer for your HVAC system? This guide can help. We’ll walk through precisely what the fan setting is and how you can use it to reduce costs during 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 remains on. Certain furnaces may continue to run at a low level with this setting, but in most cases heating or cooling isn’t being generated. The ‘Auto’ setting, on the other hand, will turn on the fan during a heating or cooling cycle and turn it off once the cycle is over.
There are pros and cons to switching on the fan setting on your thermostat, and what's ideal can depend on your unique comfort preferences.
Advantages to trying the Fan/On setting:
- You can keep the temperature in every room more balanced by enabling the fan to keep generating airflow.
- Indoor air quality should improve as continuous airflow will keep forcing airborne particles through the air filter.
- A smaller amount of start-stop cycles for the system's fan helps lengthen its life span. Because the air handler is usually part of the furnace, this means you could prevent the need for furnace repair.
Drawbacks to utilizing the Fan/On setting:
- A nonstop fan can raise your energy costs slightly.
- Constant airflow may clog your air filter in a shorter amount of time, increasing the frequency you should replace it.
Should My Thermostat Be on Fan or Auto in Summer/Winter
Through the summer, warm air may stick around 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 desired temperature. In serious heat, this could result in needing AC repair more quickly as wear and tear gets worse.
The reverse can take place in the winter. Cooler spaces like a basement will hold onto cooler air, which will eventually flow into the rest of your home. Leaving the fan running could pump more cold air upward, increasing the amount of heating you need to stay warm.
If you’re still trying to decide if you should use the fan/on setting, keep in mind that every home and family’s comfort needs will vary. Leaving the HVAC system’s fan on might be ideal 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 increase indoor air quality, helping your family breathe easier.
Your home experiences hot and cold spots. Many homes wrestle with difficult hot and cold spots that quickly return to a temperature different from the rest of the house. The fan setting can help limit these changes by constantly refreshing each room’s airflow.