Your AC fan can be set to run continuously by selecting the “Fan On” option on the thermostat. It’s a simple act, but maybe it’s something to think twice about. Is running your AC fan all the time really the best option compared to the “Fan Auto” setting that turns the AC fan on and off along with the AC cooling function? Here are some facts to think about when considering which fan setting is best for running the central air conditioner.

Benefits of “Fan On” Operation

• Starting and stopping the fan as the AC compressor cycles on and off actually imposes more wear and tear on the fan motor than running the fan continuously.
• Air quality may benefit if the fan is always running and pushing air through the filter constantly.
• If air circulation is insufficient in certain areas of your home, consider that cooling may be distributed more widely if the fan runs continuously.

Why “Fan Auto” May Be Better

• Indoor humidity increases when the fan runs in continuous mode. The humidity level is an important component of comfort inside a house. The air conditioner plays a vital role in removing humidity from indoor air. When both the fan and the AC turn off simultaneously, moisture extracted from the air that has accumulated on the indoor evaporator coil flows into a drain line and is removed from the house. If the fan runs continuously, however, this moisture does not have time to drain away. Instead, the moisture simply evaporates into water vapor again and is blown into the house, raising the humidity level and reducing your family’s comfort.
• Another fact of “Fan On” operation is higher operating costs. The fan in a typical AC air handler consumes 500 watts of electricity. If the fan is set to run continuously, the energy consumption is the equivalent of running a refrigerator all year.

For more facts about the best AC fan setting for your home, talk to the cooling professionals at Jackson & Sons.