Once the weather is cooling off, you are probably concerned about how you’ll prepare your heating and cooling. After all, HVAC expenses can add up to a significant portion of your monthly electric bill. To try and find ways to reduce costs, some homeowners take a closer look at their thermostat. Is there a setting they could use to increase efficiency?
Most thermostats have a ‘Fan’ or ‘Fan On’ setting. But if the fan is on during a typical cycle, what will the fan setting offer for your HVAC system? This guide will help. We’ll walk through precisely what the fan setting is and how you can use it to save money 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. Certain furnaces can run at a low level with this setting, but for the most part heating or cooling isn’t being produced. The ‘Auto’ setting, on the other hand, will run the fan during a heating or cooling cycle and turn it off after the cycle is complete.
There are pros and cons to trying the fan setting on your thermostat, and what's ideal should depend on your distinct comfort needs.
Advantages to using the Fan/On setting:
- You can keep the temperature in each room more balanced by permitting the fan to keep running.
- Indoor air quality can increase since constant airflow will keep passing airborne pollutants into the air filter.
- Fewer start-stop cycles for the system's fan helps extend its life span. Since the air handler is often part of the furnace, this means you can avoid needing furnace repair.
Disadvantages to using the Fan/On setting:
- A constant fan can raise your energy expenses slightly.
- Constant airflow could clog your air filter up more quickly, increasing the frequency you should replace it.
Should My Thermostat Be on Fan or Auto in Summer/Winter
Through the summer, warm air can persist in unfinished spaces like 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 preserve the set temperature. In serious heat, this may result in needing AC repair more regularly as wear and tear increases.
The reverse can take place in the winter. Cooler spaces like a basement will hold onto cooler air, which can eventually make its way 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 determine if you should use the fan/on setting, keep in mind that every home and family’s comfort needs are not the same. Leaving the HVAC system’s fan on might be best 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 enhance indoor air quality, helping your family breathe easier.
Your home deals with hot and cold spots. Many homes wrestle with persistent hot and cold spots that quickly shift to a temperature different from the rest of the house. The fan setting might help minimize these changes by constantly refreshing each room’s ventilation.