Solved: Should My Thermostat Be Set to Auto or Fan?

Once the weather is cooling off, you might be thinking about how you’ll take full advantage of your heating and cooling. After all, HVAC expenses frequently add up to a big chunk of your monthly electric bill. To figure out new ways to lower their HVAC bill, some owners look closely at their thermostat. Could there be a setting they should use to increase efficiency?

The majority of thermostats come with a ‘Fan’ or ‘Fan On’ setting. But if the fan is on during a regular cycle, what will the fan setting provide for your HVAC system? This guide should help. We’ll walk through what exactly the fan setting is and when you can use it to save money over the summer or winter.

Should I Use My Thermostat’s Fan Setting?

For the bulk of thermostats, the fan setting indicates that the system’s blower fan keeps running. A few furnaces will run at a low level in 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 over a heating or cooling cycle and shut it off when the cycle is finished.

There are pros and cons to using the fan setting on your thermostat, and the ideal option {will|can|should]] depend on your personal comfort requirements.

Advantages to utilizing the Fan/On setting:

• You can keep the temperature in each room more uniform by enabling the fan to keep circulating air.
• Indoor air quality will be highest since constant airflow will keep moving airborne particles into the air filter.
• Fewer start-stop cycles for the blower fan helps expand its life span. Because the air handler is typically a component of the furnace, this means you can prevent the need for furnace repair.

Disadvantages to using the Fan/On setting:

• A nonstop fan could increase your energy costs by a small margin.
• Constant airflow may clog your air filter up more quickly, 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

In the summer, warm air may persist in unfinished spaces including the attic or an attached garage. If you leave the fan on, your HVAC system can draw this warm air into the rest of your home, compelling the HVAC system to work more to maintain the set temperature. In serious heat, this could lead to needing AC repair more often as wear and tear increases.

The opposite can happen over the winter. Cooler spaces like a basement will hold onto cooler air, which will eventually make its way into the rest of your home. Leaving the fan setting on could pull 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, don’t forget that every home and family’s comfort needs are not the same. Leaving the HVAC system’s fan on may be ideal 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 should help to enhance indoor air quality, helping your family breathe easier.

Your home deals with hot and cold spots. Many homes wrestle with persistent hot and cold spots that quickly shift to a temperature different from the rest of the house. The fan setting might help lessen these changes by consistently refreshing each room’s ventilation.