Once the weather is cooling off, you are probably thinking 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 try and find ways to reduce costs, some people look closer at their thermostat. Is there a setting they could use to boost efficiency?
The majority of thermostats include both a ‘Fan’ or ‘Fan On’ setting. But if the fan is going during a regular cycle, what can the fan setting provide for an HVAC system? This guide will help. We’ll walk through what exactly 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 the bulk of thermostats, the fan setting indicates that the air handler’s blower fan remains on. A few furnaces may continue to operate at a low level with this setting, but in most cases heating or cooling isn’t being produced. The ‘Auto’ setting, on the other hand, will turn on the fan during a heating or cooling cycle and shut it off once the cycle is complete.
There are advantages and disadvantages to using the fan setting on your thermostat, and the ideal option should depend on your unique comfort requirements.
Advantages to using the Fan/On setting:
- You can keep the temperature throughout your home more uniform by enabling the fan to keep generating airflow.
- Indoor air quality can increase because constant airflow will keep forcing airborne contaminants into the air filter.
- Fewer start-stop cycles for the system's fan helps extend its life span. Since the air handler is typically part of the furnace, this means you can prevent the need for furnace repair.
Drawbacks to using the Fan/On setting:
- A nonstop fan will likely raise your energy expenses by a small margin.
- Continuous airflow can 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
In the summer, warm air will sometimes stick around in unfinished spaces like the attic or an attached garage. If you use the fan setting, your HVAC system may pull this warm air into the rest of your home, compelling the HVAC system to work harder to preserve the set temperature. In serious heat, this may result in needing AC repair more quickly as wear and tear grows.
The opposite can take place over the winter. Cooler spaces like a basement will hold onto cooler air, which will eventually drift into the rest of your home. Keeping the fan on could draw more cold air upward, increasing the amount of heating you need to keep 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 could work 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 should help to improve indoor air quality, helping your family breathe easier.
Your home deals with hot and cold spots. Lots of homes wrestle with persistent hot and cold spots that quickly evolve to a temperature different from the rest of the house. The fan setting should help lessen these changes by consistently refreshing each room’s airflow.