The most energy-efficient setting for your HVAC system depends on various factors, including the climate, your comfort preferences, and the insulation of your apartment. Generally, setting the HVAC fan to "Auto" is more energy-efficient compared to keeping the fan "On" continuously.
Here's why:
Auto Setting: When the fan is set to "Auto," it only runs when the heating or cooling system is actively running. Once the desired temperature is reached, both the compressor (for cooling) and the furnace (for heating) turn off, and the fan stops running as well. The fan only runs during heating or cooling cycles, which helps save energy since it's not running constantly.
On Setting: When the fan is set to "On," it runs continuously, even when the heating or cooling system is not actively running. The continuous operation of the fan can lead to increased energy consumption, as it circulates air throughout the apartment regardless of whether the heating or cooling is needed.
By using the "Auto" setting, the fan operates more efficiently, and you can save energy and reduce utility costs. When the HVAC system is not actively heating or cooling, the fan remains off, allowing the apartment to maintain its temperature passively for some time. Additionally, running the fan continuously can lead to slightly more wear and tear on the fan motor and increase the need for filter replacements, further adding to maintenance costs.
If you find that setting the fan to "Auto" makes some areas of your apartment less comfortable due to uneven temperature distribution, you might want to consider adjusting your HVAC system's settings or exploring other options like using fans or adjusting the vents to optimize airflow. Consulting with an HVAC professional can help you find the best balance between comfort and energy efficiency for your specific apartment and needs.