Updated On: 10/11/23

When you set the thermostat of your HVAC system, the unit heats or cools, and fans blow conditioned air into the living space. When the set point is reached, the heating or cooling function stops. However, thermostats have settings that control fans independently. With the “auto” setting, fans turn off when the air conditioner shuts off. With the “on” setting, fans run continuously. There are advantages and disadvantages to each setting. An AC professional can help you save energy and increase comfort by showing you how to adjust your thermostat.

Auto Thermostat Function

Most thermostats allow you to control how long fans operate. On the auto setting, fans stay on throughout the heating or cooling cycle. When the desired temperature is reached, the unit and the fans stop. Fans use less energy on the auto setting because they only run when the furnace or air conditioner is on. In addition, fans last longer with fewer starts and stops.

Benefits of Auto Thermostat Function:
  • Auto settings help reduce energy consumption
  • Auto thermostat settings can result in lower utility bills
  • Your HVAC system experiences less wear and tear.
Disadvantage of Auto Thermostat Function:
  • No air circulation when fans are off
  • Hot or cold spots may be felt in a room
  • Auto settings may have a slight delay in responding to temperature changes>/li>

If uneven indoor temperatures cause discomfort, call a licensed air conditioning repair company to investigate the issue.

On Thermostat Function

Fans switched to the on function run continuously. When the desired temperature is reached, the heating or cooling component powers down. However, fans continue to run. Fans help keep the air more evenly distributed. Because of this, indoor air quality devices, such as UV filters and air filters, continue to operate.

Benefits of On Thermostat Function:
  • Continuous air circulation can help remove excess moisture from the air
  • Running the fan continuously can help distribute conditioned air more evenly
  • HVAC system can respond more quickly to temperature fluctuations
Disadvantage of On Thermostat Function:
  • On setting uses more power, resulting in higher utility bills
  • Air moving constantly through the system may cause air filters to clog up more frequently
  • The constant operation of the fan can produce disruptive noise

During the winter, the air blowing through registers feels cold when the furnace is not on. During the summer, rooms may feel more humid because fans do not remove moisture, an important issue in the humid climate of the Houston area. If you are experiencing these issues, contact our team today!

Other Options

New technology offers other options. Variable speed units respond to heating and cooling demands. Unlike standard units that are either on or off, these systems run at low power for longer periods when demand is low and power up when temperatures rise. This saves energy, reduces wear and tear on components, and eliminates hot and cold spots in the living space.

For residential and commercial AC repair, AC installation and AC maintenance services, call AirDepot. Our NATE-certified technicians’ service all brands of HVAC equipment. We take the time to explain problems and offer solutions that meet your indoor comfort needs and budget. For more information about using your thermostat to regulate energy efficiency and comfort and other Cypress AC services, call AirDepot today!