As the weather begins to cool off, you may be thinking about how you’ll take full advantage of your heating and cooling. After all, HVAC bills frequently add up to a large piece of your monthly electric bill. To try and find ways to reduce costs, some people take a closer look at their thermostat. Could there be a setting they should use to increase efficiency?
The bulk of thermostats have a ‘Fan’ or ‘Fan On’ setting. But if the fan is running during a normal cycle, what can the fan setting offer for your HVAC system? This guide can help. We’ll review precisely what the fan setting is and whether you can use it to cut costs over the summer or winter.
What Is the Fan Setting on My Thermostat?
For the bulk of thermostats, the fan setting indicates that the system's blower fan stays on. A few furnaces will 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 run the fan during a heating or cooling cycle and switch 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 will depend on your personal comfort preferences.
Advantages to using the Fan/On setting:
- You can keep the temperature in each room more consistent by permitting the fan to keep running.
- Indoor air quality should improve because constant airflow will keep moving airborne pollutants through the air filter.
- Fewer start-stop cycles for the blower fan helps extend its life span. Since the air handler is usually part of the furnace, this means you can minimize the risk of needing furnace repair.
Drawbacks to using the Fan/On setting:
- A continuous fan could increase your energy expenses slightly.
- Continuous airflow could clog your air filter in a shorter amount of time, 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 like 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 run longer to maintain the preferred temperature. In severe heat, this can result in needing AC repair more often as wear and tear grows.
The opposite can take place over the winter. Cooler spaces like a basement will hold onto cooler air, which will 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 decide if you should use the fan/on setting, don’t forget that every home and family’s comfort needs are different. Leaving the HVAC system’s fan on could be ideal for you if:
Someone in your household has allergies. Allergies and similar respiratory conditions can be tough on the family. Leaving the fan on is more likely to enhance indoor air quality, helping your family breathe easier.
Your home has hot and cold spots. All kinds 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 steadily refreshing each room’s airflow.