When the weather starts to cool off, you are probably concerned about how you’ll prepare your heating and cooling. After all, HVAC bills routinely contribute a large chunk of your monthly electric bill. To try and find ways to lower their HVAC bill, some homeowners take a closer look at their thermostat. Maybe there’s a setting they should use to increase efficiency?
Most thermostats come with a ‘Fan’ or ‘Fan On’ setting. But if the fan is running during a typical cycle, what can the fan setting provide for the HVAC system? This guide will help. We’ll review precisely what the fan setting is and how you can use it to reduce costs over the summer or winter.
What Is the Fan Setting on My Thermostat?
For most thermostats, the fan setting means that the system's blower fan remains on. Some furnaces may continue to run at a low level in this setting, but in general heating or cooling isn’t being made. The ‘Auto’ setting, on the other hand, will start the fan through a heating or cooling cycle and shut it off after the cycle is finished.
There are benefits and drawbacks to using the fan setting on your thermostat, and what's ideal {will|can|should]] depend on your distinct comfort requirements.
Advantages to using the Fan/On setting:
- You can keep the temperature throughout your home more balanced by enabling the fan to keep circulating air.
- Indoor air quality should improve since continuous airflow will keep moving airborne pollutants into the air filter.
- A smaller amount of start-stop cycles for the system's fan helps lengthen its life span. As the air handler is often a component of the furnace, this means you could minimize the risk of needing furnace repair.
Downsides to using the Fan/On setting:
- A constant fan can add to your energy costs somewhat.
- Continuous airflow could 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 can persist in unfinished spaces such as the attic or an attached garage. If you leave the fan on, your HVAC system might gradually move this warm air into the rest of your home, pushing the HVAC system to run longer to maintain the desired temperature. In extreme heat, this can result in needing AC repair more quickly as wear and tear increases.
The reverse can happen in the winter. Cooler spaces such as a basement will hold onto cooler air, which can eventually flow 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 determine if you should use the fan/on setting, remember that every home and family’s comfort needs will vary. Leaving the HVAC system’s fan on might work for you if:
Someone in your household deals with allergies. Allergies and other 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 experiences hot and cold spots. Lots of homes deal with persistent hot and cold spots that quickly shift to a temperature different from the rest of the house. The fan setting should help minimize these changes by consistently refreshing each room’s ventilation.
