As the weather begins to cool off, you may be wondering about how you’ll make the most of your heating and cooling. After all, HVAC expenses routinely contribute a large piece of your monthly electric bill. To learn new ways to save, some homeowners take a closer look at their thermostat. Maybe there’s a setting they could use to improve efficiency?
The majority of thermostats have a ‘Fan’ or ‘Fan On’ setting. But if the fan is going during a typical cycle, what does the fan setting offer for your HVAC system? This guide should help. We’ll review precisely what the fan setting is and how you can use it to reduce costs during the summer or winter.
What Is the Fan Setting on My Thermostat?
For the bulk of thermostats, the fan setting means that the system's blower fan keeps running. Certain furnaces will generate heat at a low level with this setting, but in general heating or cooling isn’t being made. The ‘Auto’ setting, in contrast, will turn on the fan through a heating or cooling cycle and turn it off when the cycle is complete.
There are pros and cons to switching on the fan setting on your thermostat, and whether you do or don’t will depend on your personal comfort requirements.
Advantages to switching to the Fan/On setting:
- You can keep the temperature in each room more uniform by enabling the fan to keep circulating air.
- Indoor air quality can increase as steady airflow will keep passing airborne pollutants into the air filter.
- Fewer start-stop cycles for the blower fan helps expand its life span. Since the air handler is usually part of the furnace, this means you could avoid needing furnace repair.
Drawbacks to switching to the Fan/On setting:
- A continuous fan could increase your energy expenses slightly.
- Nonstop airflow may clog your air filter soon, increasing the frequency you’ll need to replace it.
Should My Thermostat Be on Fan or Auto in Summer/Winter
In the summer, warm air can persist in unfinished spaces including the attic or an attached garage. If you leave the fan on, your HVAC system can draw this warm air into the rest of your home, pushing the HVAC system to run longer to maintain the set temperature. In severe heat, this can result in needing AC repair more often 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 pull 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, don’t forget that every home and family’s comfort needs will vary. 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 tough on the family. Leaving the fan on should help to improve indoor air quality, helping your family breathe easier.
Your home experiences hot and cold spots. All kinds of homes wrestle with persistent hot and cold spots that quickly return to a temperature different from the rest of the house. The fan setting can help minimize these changes by consistently refreshing each room’s airflow.