As the weather starts to cool off, you may be wondering about how you’ll make the most of your heating and cooling. After all, HVAC bills frequently make up a big portion of your monthly electric bill. To learn new ways to lower their HVAC bill, some people take a closer look at their thermostat. Maybe there’s a setting they can use to increase efficiency?
Most thermostats come with a ‘Fan’ or ‘Fan On’ setting. But if the fan is on during a regular cycle, what can the fan setting offer for an HVAC system? This guide should help. We’ll review what exactly the fan setting is and how you can use it to save money during the summer or winter.
What Is the Fan Setting on My Thermostat?
For most thermostats, the fan setting signifies that the system's blower fan stays on. Some furnaces will run at a low level with this setting, but for the most part heating or cooling isn’t being generated. The ‘Auto’ setting, in contrast, will start the fan over a heating or cooling cycle and turn it off when the cycle is complete.
There are advantages and disadvantages to trying the fan setting on your thermostat, and the ideal option should depend on your unique comfort requirements.
Advantages to trying the Fan/On setting:
- You can keep the temperature in each room more uniform by permitting the fan to keep circulating air.
- Indoor air quality can increase since constant airflow will keep passing airborne pollutants through the air filter.
- A smaller amount of start-stop cycles for the HVAC fan helps expand its life span. As the air handler is often connected to the furnace, this means you might avoid needing furnace repair.
Drawbacks to utilizing the Fan/On setting:
- A continuous fan will likely increase your energy costs somewhat.
- Constant airflow could 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 can persist in unfinished spaces such as the attic or an attached garage. If you leave the fan on, your HVAC system can gradually move this warm air into the rest of your home, compelling the HVAC system to work harder to keep up with the desired temperature. In severe heat, this could lead to needing AC repair more regularly as wear and tear gets worse.
The opposite can take place over 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 setting on could draw more cold air upward, increasing the amount of heating you need to keep warm.
If you’re still trying to decide if you should switch to the fan/on setting, keep in mind that every home and family’s comfort needs are different. Leaving the HVAC system’s fan on may be best for you if:
Someone in your household suffers from allergies. Allergies and other respiratory conditions can be hard on the family. Leaving the fan on is more likely to improve indoor air quality, helping your family breathe easier.
Your home has hot and cold spots. Many homes wrestle with difficult hot and cold spots that quickly shift to a temperature different from the rest of the house. The fan setting might help lessen these changes by steadily refreshing each room’s ventilation.