Once the weather starts to cool off, you may be thinking about how you’ll prepare your heating and cooling. After all, HVAC costs routinely contribute a large piece of your monthly electric bill. To figure out new ways to save, some homeowners take a closer look at their thermostat. Could there be a setting they could use to increase 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 will 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 majority of thermostats, the fan setting means that the HVAC blower fan remains on. Certain furnaces can run at a low level in this setting, but for the most part heating or cooling isn’t being made. The ‘Auto’ setting, conversely, will turn on the fan through a heating or cooling cycle and turn it off once the cycle is complete.
There are benefits and drawbacks to trying the fan setting on your thermostat, and whether you do or don’t should depend on your unique comfort requirements.
Advantages to trying the Fan/On setting:
- You can keep the temperature in every room more balanced by permitting the fan to keep running.
- Indoor air quality can increase since steady airflow will keep moving airborne pollutants into the air filter.
- A smaller number of start-stop cycles for the HVAC fan helps lengthen its life span. Since the air handler is typically part of the furnace, this means you could avoid needing furnace repair.
Drawbacks to using the Fan/On setting:
- A constant fan will likely raise your energy bills somewhat.
- Constant airflow can 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
In the summer, warm air will sometimes linger in unfinished spaces including the attic or an attached garage. If you leave the fan on, your HVAC system might draw this warm air into the rest of your home, pushing the HVAC system to work harder to keep up with the set temperature. In serious heat, this could lead to needing AC repair more regularly as wear and tear gets worse.
The reverse can occur over the winter. Cooler spaces like a basement will hold onto cooler air, which may eventually flow into the rest of your home. Leaving the fan running may pull more cold air upward, increasing the amount of heating you need to remain warm.
If you’re still trying to decide if you should try the fan/on setting, remember that every home and family’s comfort needs will vary. Leaving the HVAC system’s fan on could work for you if:
Someone in your household suffers from allergies. Allergies and similar respiratory conditions can be stressful on the family. Leaving the fan on should help to enhance indoor air quality, helping your family breathe easier.
Your home experiences hot and cold spots. All kinds of homes deal with stubborn hot and cold spots that quickly evolve to a temperature different from the rest of the house. The fan setting might help limit these changes by constantly refreshing each room’s supply of air.