If you have a programmable thermostat, you may wonder what the difference is between the “On” and “Auto” thermostat settings.

Both selections have advantages and disadvantages, and it’s really a decision that you as a homeowner make in order to keep your home at your preferred comfort level.

Here’s a comparison showing the differences between each of the settings.

“On” Setting

Setting your thermostat to the “On” setting results in the furnace fan running constantly.

Advantages

  • Improves air quality because air is constantly circulating through the air filters which help remove pollutants and contaminants from the air you breathe.

Disadvantages

  • Diminishes air quality in your home if you neglect to change your air filter on a regular basis.
  • Requires more frequent changing of the air filters, which will cost more money.
  • With the furnace fan constantly running, it will increase your monthly energy bill.
  • Because the fan is running constantly whether the heat is on or not, it’s possible for cold air to circulate throughout your home which is counterproductive to the warm, toasty environment you want.

“Auto” Setting

To use the “Auto” setting, you program the thermostat to maintain a set temperature. When your furnace receives a signal from the thermostat that the current temperature has dropped below the set temperature, the furnace automatically kicks in.

The “Auto” setting keeps a steady temperature without the furnace fan running continuously.

Advantages

  • The furnace fan isn’t running constantly, which saves you money on your monthly energy bill.
  • Because the fan isn’t running constantly, it conserves a lot more energy.
  • Furnace filters don’t need changing as often.

Disadvantages

  • Because the furnace is stopping and starting often to maintain the set temperature, it puts more strain on the furnace overall and specifically, the motor.
  • Because the motor is used more, the odds increase for it to fail or need replacement sooner or more often.
  • The possibility for the fan to blow out cold air when the motor starts the furnace is also possible with the “Auto” setting.

After reviewing the advantages and disadvantages for each of the settings, you might decide to change from one setting to the other.

In either case, problems with air distribution or the need for replacement parts can be kept to a minimum with scheduled inspections and maintenance from your trusted local HVAC company.
In Sant aRosa and surrounding Sonoma County communities, Dale HCS is the trusted dealer to call. Reach out today to schedule a seasonal cleaning and inspection of your programmable thermostat.