As the weather is cooling off, you may be wondering about how you’ll take full advantage of your heating and cooling. After all, HVAC costs can make up a large portion of your monthly electric bill. To figure out new ways to lower their HVAC bill, some owners look closely at their thermostat. Maybe there’s a setting they should use to boost efficiency?
Most thermostats include both a ‘Fan’ or ‘Fan On’ setting. But if the fan is on during a typical cycle, what will the fan setting provide for an HVAC system? This guide will help. We’ll walk through what exactly the fan setting is and whether you can use it to reduce costs in the summer or winter.
What Is the Fan Setting on My Thermostat?
For the majority of thermostats, the fan setting means that the HVAC blower fan stays on. A few furnaces will run at a low level in this setting, but in most cases heating or cooling isn’t being made. The ‘Auto’ setting, on the other hand, will turn on the fan over a heating or cooling cycle and turn it off after the cycle is finished.
There are advantages and disadvantages to switching on the fan setting on your thermostat, and what's ideal can depend on your distinct comfort preferences.
Advantages to trying the Fan/On setting:
- You can keep the temperature in every room more consistent by enabling the fan to keep running.
- Indoor air quality can increase since steady airflow will keep moving airborne contaminants into the air filter.
- A smaller number of start-stop cycles for the blower fan helps expand its life span. Because the air handler is typically a component of the furnace, this means you could minimize the risk of needing furnace repair.
Disadvantages to switching to the Fan/On setting:
- A nonstop fan could raise your energy costs slightly.
- Continuous airflow can clog your air filter up more quickly, increasing the frequency you will want to replace it.
Should My Thermostat Be on Fan or Auto in Summer/Winter
During the summer, warm air may stick around in unfinished spaces such as the attic or an attached garage. If you leave the fan on, your HVAC system may draw this warm air into the rest of your home, forcing the HVAC system to work more to preserve the preferred temperature. In extreme heat, this could result in needing AC repair more regularly as wear and tear grows.
The opposite can take place during 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 will sometimes pull more cold air upward, increasing the amount of heating you need to keep warm.
If you’re still trying to determine 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 deals with allergies. Allergies and similar respiratory conditions can be tough on the family. Leaving the fan on can help to enhance indoor air quality, helping your family breathe easier.
Your home deals with hot and cold spots. All kinds of homes wrestle with difficult hot and cold spots that quickly shift to a temperature different from the rest of the house. The fan setting can help limit these changes by steadily refreshing each room’s ventilation.