As the weather begins to cool off, you may be concerned about how you’ll take full advantage of your heating and cooling. After all, HVAC costs routinely add up to a significant chunk of your monthly electric bill. To learn new ways to lower their HVAC bill, some people take a closer look at their thermostat. Is there a setting they could use to boost efficiency?
The bulk of thermostats come with a ‘Fan’ or ‘Fan On’ setting. But if the fan is on during a normal cycle, what can the fan setting provide for the HVAC system? This guide can help. We’ll walk through just what the fan setting is and whether you can use it to cut costs in the summer or winter.
What Is the Fan Setting on My Thermostat?
For the bulk of thermostats, the fan setting indicates that the HVAC blower fan remains on. A few furnaces will generate heat at a low level in this setting, but in most cases heating or cooling isn’t being generated. The ‘Auto’ setting, in contrast, will start the fan through a heating or cooling cycle and shut it off after the cycle is over.
There are pros and cons to using the fan setting on your thermostat, and the ideal option can depend on your unique comfort preferences.
Advantages to utilizing the Fan/On setting:
- You can keep the temperature in every room more balanced by permitting the fan to keep generating airflow.
- Indoor air quality should improve as steady airflow will keep forcing airborne contaminants 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 usually a component of the furnace, this means you could avoid needing furnace repair.
Downsides to using the Fan/On setting:
- A continuous fan will likely increase your energy costs by a small margin.
- Continuous 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
In the summer, warm air may persist 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, compelling the HVAC system to work more to preserve the set temperature. In severe heat, this could result in needing AC repair more regularly as wear and tear gets worse.
The opposite can take place during the winter. Cooler spaces such as a basement will hold onto cooler air, which will eventually make its way 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 keep warm.
If you’re still trying to figure out if you should try the fan/on setting, remember that every home and family’s comfort needs are different. Leaving the HVAC system’s fan on may be ideal for you if:
Someone in your household suffers from allergies. Allergies and similar respiratory conditions can be hard on the family. Leaving the fan on should help to improve indoor air quality, helping your family breathe easier.
Your home has hot and cold spots. Many homes deal with difficult hot and cold spots that quickly evolve to a temperature different from the rest of the house. The fan setting should help limit these changes by steadily refreshing each room’s ventilation.