As the weather is cooling off, you are probably thinking about how you’ll prepare your heating and cooling. After all, HVAC costs can add up to a big portion of your monthly electric bill. To try and find ways to lower their HVAC bill, some people look closer at their thermostat. Maybe there’s a setting they can use to boost efficiency?

Most thermostats have a ‘Fan’ or ‘Fan On’ setting. But if the fan is on during a normal cycle, what will the fan setting provide for the HVAC system? This guide will help. We’ll review just what the fan setting is and when you can use it to reduce costs during the summer or winter.

My Thermostat Has a Fan Setting?

For the majority of thermostats, the fan setting signifies that the HVAC blower fan stays on. A few furnaces will generate heat at a low level with this setting, but for the most part heating or cooling isn’t being generated. The ‘Auto’ setting, in contrast, will run the fan over a heating or cooling cycle and switch it off when the cycle is finished.

There are pros and cons to switching on the fan setting on your thermostat, and whether you do or don’t {will|can|should]] depend on your distinct comfort requirements.

Advantages to switching to the Fan/On setting:

  • You can keep the temperature in every room more balanced by allowing the fan to keep generating airflow.
  • Indoor air quality will be highest since steady airflow will keep forcing airborne contaminants through the air filter.
  • A smaller amount of start-stop cycles for the system’s fan helps extend its life span. Since the air handler is usually connected to the furnace, this means you might prevent the need for furnace repair.

Drawbacks to utilizing the Fan/On setting:

  • A constant fan can raise your energy bills somewhat.
  • Nonstop airflow could clog your air filter soon, increasing the frequency you’ll need to replace it.

{Choosing Between|Should My Thermostat Be on|Which Setting for My Thermostat? Fan or Auto in Each Season

Through the summer, warm air will sometimes linger in unfinished spaces like 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, forcing the HVAC system to work more to keep up with the desired temperature. In severe heat, this may result in needing AC repair more quickly as wear and tear gets worse.

The opposite can take place over 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. Keeping the fan on may pull more cold air upward, increasing the amount of heating you need to stay warm.

If you’re still trying to determine if you should switch to the fan/on setting, remember that every home and family’s comfort needs will vary. Leaving the HVAC system’s fan on might be best for you if:

Someone in your household suffers from allergies. Allergies and other 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. All kinds of homes wrestle with stubborn hot and cold spots that quickly shift to a temperature different from the rest of the house. The fan setting should help minimize these changes by constantly refreshing each room’s supply of air.