Once the weather is cooling off, you are probably thinking about how you’ll take full advantage of your heating and cooling. After all, HVAC costs routinely make up a significant portion of your monthly electric bill. To try and find ways to reduce costs, some homeowners look closer at their thermostat. Could there be a setting they can use to boost efficiency?

Most thermostats have a ‘Fan’ or ‘Fan On’ setting. But if the fan is going during a normal cycle, what does the fan setting offer for your HVAC system? This guide will help. We’ll review precisely what the fan setting is and how you can use it to reduce costs over the summer or winter.

What Is the Fan Setting on My Thermostat?

For most thermostats, the fan setting means that the HVAC blower fan keeps running. A few furnaces may continue to operate at a low level with this setting, but in most cases heating or cooling isn’t being made. The ‘Auto’ setting, on the other hand, will turn on the fan during a heating or cooling cycle and switch it off once the cycle is over.

There are benefits and drawbacks to using the fan setting on your thermostat, and whether you do or don’t {will|can|should]] depend on your unique comfort needs.

Advantages to trying the Fan/On setting:

  • You can keep the temperature in every room more uniform by permitting the fan to keep generating airflow.
  • Indoor air quality will be highest since steady airflow will keep forcing airborne contaminants into the air filter.
  • Fewer start-stop cycles for the system’s fan helps lengthen its life span. Because the air handler is usually a component of the furnace, this means you might avoid needing furnace repair.

Downsides to utilizing the Fan/On setting:

  • A constant fan will likely increase your energy bills by a small margin.
  • Continuous airflow can clog your air filter in a shorter amount of time, increasing the frequency you will want to replace it.

{Choosing Between|Should My Thermostat Be on|Which Setting for My Thermostat? Fan or Auto in Summer/Winter

Through the summer, warm air may stick around in unfinished spaces like the attic or an attached garage. If you use the fan setting, your HVAC system might pull this warm air into the rest of your home, compelling the HVAC system to work harder to preserve the desired temperature. In extreme heat, this may result in needing AC repair more regularly as wear and tear grows.

The reverse can happen in the winter. Cooler spaces like a basement will hold onto cooler air, which can eventually flow into the rest of your home. Keeping the fan on could pull more cold air upward, increasing the amount of heating you need to keep warm.

If you’re still trying to figure out if you should use the fan/on setting, remember that every home and family’s comfort needs are not the same. Leaving the HVAC system’s fan on may 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 can help to increase indoor air quality, helping your family breathe easier.

Your home has hot and cold spots. Lots of homes deal with persistent hot and cold spots that quickly evolve to a temperature different from the rest of the house. The fan setting should help limit these changes by consistently refreshing each room’s supply of air.