Once the weather starts to cool off, you might be wondering about how you’ll prepare your heating and cooling. After all, HVAC costs routinely add up to a large chunk of your monthly electric bill. To figure out new ways to save, some owners take a closer look at their thermostat. Is there a setting they could use to increase efficiency?
The bulk of thermostats come with a ‘Fan’ or ‘Fan On’ setting. But if the fan is on during a typical cycle, what will the fan setting provide 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 most thermostats, the fan setting indicates that the HVAC blower fan remains on. A few furnaces can run at a low level in this setting, but in most cases heating or cooling isn’t being produced. The ‘Auto’ setting, in contrast, will turn on the fan through a heating or cooling cycle and switch it off when the cycle is complete.
There are benefits and drawbacks to using the fan setting on your thermostat, and what's ideal {will|can|should]] depend on your personal comfort needs.
Advantages to utilizing the Fan/On setting:
- You can keep the temperature throughout your home more balanced by permitting the fan to keep generating airflow.
- Indoor air quality will be highest since steady airflow will keep moving airborne contaminants through the air filter.
- A smaller amount of start-stop cycles for the blower fan helps lengthen its life span. Because the air handler is typically part of the furnace, this means you could prevent the need for furnace repair.
Drawbacks to switching to the Fan/On setting:
- A nonstop fan will likely add to your energy costs somewhat.
- Nonstop airflow can clog your air filter in a shorter amount of time, increasing the frequency you should replace it.
Should My Thermostat Be on Fan or Auto in Summer/Winter
Through the summer, warm air will sometimes persist in unfinished spaces including the attic or an attached garage. If you keep the fan running, your HVAC system might gradually move this warm air into the rest of your home, forcing the HVAC system to work more to maintain the desired temperature. In serious heat, this may lead to needing AC repair more regularly as wear and tear grows.
The opposite can occur in the winter. Cooler spaces such as a basement will hold onto cooler air, which will eventually flow into the rest of your home. Keeping the fan on may draw more cold air upward, increasing the amount of heating you need to stay warm.
If you’re still trying to decide if you should switch to 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 could be best 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 can help to improve indoor air quality, helping your family breathe easier.
Your home deals with hot and cold spots. Many homes deal with persistent hot and cold spots that quickly shift to a temperature different from the rest of the house. The fan setting can help lessen these changes by steadily refreshing each room’s supply of air.