Updated 10/16/2024

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. According to consumer data from the U.S. Department of Energy, proper utilization of thermostat settings and automated schedules is one of the easiest ways for homeowners to save up to 10% a year on heating and cooling costs.

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.
Disadvantages of the Auto Thermostat Function:
  • No air circulation when the 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

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

High Energy Bills Even on the “Auto” Setting?

If your utility bills are skyrocketing despite keeping your system on ‘Auto,’ your air conditioner is likely losing its operational efficiency. Let our local, NATE-certified experts run a precision tune-up to lower your monthly costs.  Schedule Your $69 Seasonal AC Tune-Up Now

On Thermostat Function

Fans switched to the on function and ran 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 the 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 systems can respond more quickly to temperature fluctuations
Disadvantages of the 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 the 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!

Upgrade to a WiFi-Enabled Smart Thermostat

Take complete control of your home’s energy efficiency and comfort. Upgrading to a smart thermostat eliminates the “Auto vs. On” guesswork and cuts down on utility waste automatically.  Click Here to Request a Smart Thermostat Consultation

Other Options

Air Depot provides professional installation on the Aere Smart Thermostats. 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 AC repair, AC installation, and AC maintenance services, call Air Depot Cooling & Heating. 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 Air Depot Cooling & Heating today!

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Air Depot Cooling & Heating
Air Depot Cooling & Heating

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