As the weather is cooling off, you are probably concerned about how you’ll make the most of your heating and cooling. After all, HVAC expenses can make up a big chunk of your monthly electric bill. To figure out new ways to save, some people look closely at their thermostat. Maybe there’s a setting they can use to boost efficiency?
The majority of thermostats come with a ‘Fan’ or ‘Fan On’ setting. But if the fan is running during a typical cycle, what will the fan setting provide for an HVAC system? This guide can help. We’ll review just what the fan setting is and when you can use it to save money during the summer or winter.
What Is the Fan Setting on My Thermostat?
For the bulk of thermostats, the fan setting signifies that the HVAC blower fan stays on. Certain furnaces will run at a low level with this setting, but in general heating or cooling isn’t being produced. The ‘Auto’ setting, conversely, will run the fan through a heating or cooling cycle and shut it off after the cycle is over.
There are pros and cons to trying the fan setting on your thermostat, and what's ideal should depend on your unique comfort requirements.
Advantages to utilizing the Fan/On setting:
- You can keep the temperature in every room more consistent by enabling the fan to keep circulating air.
- Indoor air quality can increase as constant airflow will keep passing airborne particles through the air filter.
- A smaller amount of start-stop cycles for the HVAC fan helps lengthen its life span. As the air handler is typically a component of the furnace, this means you can avoid needing furnace repair.
Drawbacks to switching to the Fan/On setting:
- A continuous fan will likely increase your energy expenses slightly.
- Nonstop airflow may clog your air filter soon, increasing the frequency you will want to replace it.
Should My Thermostat Be on Fan or Auto in Summer/Winter
During 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 may draw this warm air into the rest of your home, compelling the HVAC system to run longer to preserve the desired temperature. In extreme heat, this may lead to needing AC repair more quickly as wear and tear grows.
The opposite can happen during the winter. Cooler spaces like a basement will hold onto cooler air, which can eventually drift 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 figure out if you should switch to the fan/on setting, don’t forget 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 deals with allergies. Allergies and similar respiratory conditions can be stressful on the family. Leaving the fan on is more likely to increase indoor air quality, helping your family breathe easier.
Your home has hot and cold spots. All kinds of homes deal with difficult hot and cold spots that quickly shift to a temperature different from the rest of the house. The fan setting should help lessen these changes by constantly refreshing each room’s supply of air.