Fan On vs. Auto: How Should You Set Your Thermostat Fan?

It isn’t difficult to choose a temperature setting on the thermostat. You simply select “heat” or “cool” and make your desired temperature adjustments. Setting your thermostat fan is a bit more challenging, however. Here’s some helpful advice on when to use the “on” and “auto” settings.

When to Choose “On”

When the fan is set to “on,” the blower operates continuously even when the heating or cooling equipment cycles off. Leaving the fan running reduces wear and tear on the motor since it’s not starting and stopping repeatedly. It’s also beneficial to boost filtration, but leaving it on this setting has more drawbacks than benefits.

When it runs nonstop, the fan consumes more energy, and the air filter needs frequent replacement. Even worse, moisture-laden air that builds up in the ducts when the A/C cycles off is redistributed throughout the home, adding to its workload and increasing your cooling costs.

When to Select “Auto”

When the fan is on “auto,” it cycles on and off in tandem with the HVAC equipment. Leaving it on this setting throughout the summer makes the cooling equipment’s job easier, since it doesn’t have to overcome re-circulated heat and humidity during every cycle. This helps prevent unnecessary energy consumption along with extra strain and wear on the air conditioner.

One potential drawback of using the “auto” fan setting is that the living space can start to feel stuffy and warm in between A/C cycles. If you’re concerned about enhancing comfort, air quality and energy savings, consider a variable-speed air handler when it’s time to upgrade your cooling equipment. Even with the fan on “auto,” variable-speed units run nonstop on low, so they can efficiently keep the temperature consistent as well as boost filtration and humidity control.

If you have questions about setting your thermostat fan, contact us at Sobieski Services, Inc. Our goal is to help our customers in Delaware, Pennsylvania, Maryland and New Jersey learn more about energy and home comfort issues – especially HVAC and plumbing issues – so they can save money and live in healthier, more comfortable homes.

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