Have you ever wondered which thermostat fan setting is best: “on” or “auto”? Some sources will tell you “on” is best, while a different source may recommend “auto.” Keep reading to learn the differences between the two settings, the impact they have on comfort, indoor air quality and energy bills, and decide for yourself which is best for your needs when setting your thermostat.
Understanding Fan Modes
The thermostat is the go-to device for setting temperatures to cool and heat your home. The thermostat also controls fan operation with the fan modes “on” and “auto.” If the fan is set to “on,” the fan continues to run after the A/C or furnace has stopped cooling and heating. When the fan is set to “auto,” the fan only runs during cooling and heating operation.
Setting Your Thermostat
Learn about the effects “on” and “auto” have on your home and decide which best serves your needs:
- Comfort and efficiency: The fan motor can use a lot of energy, especially in older HVAC systems. If you run the fan continuously in the “on” mode for air circulation, consider running ceiling fans instead. You’ll save energy, feel cooler on hot days and move heat around your home more efficiently during the heating months.
- Humidity control: Indoor humidity contributes to higher cooling costs, discomfort and the proliferation of many microorganisms. The A/C system relieves high humidity levels to some degree as an incidental effect of the cooling process. When the thermostat is in the “on” mode with continuous airflow, the condensate evaporates and is returned to the living spaces. “Auto” mode helps control high humidity better.
- Indoor air quality: With continuous operation and airflow, the “on” setting cleans indoor air constantly. For occupants suffering respiratory ailments, the “on” setting is better. However, if healthful indoor air quality and humidity control are high on your list for healthy living, consider installing a whole-house air purifier and a whole-home dehumidifier.
For more information about setting your thermostat, please contact Arpi’s Industries Ltd. We’ve provided exceptional services for Calgary residents and businesses for more than 50 years.
Our goal is to help educate our customers in Calgary, Alberta about energy and home comfort issues (specific to HVAC systems). For more information, download our free Home Comfort Resource guide.
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