On vs. Auto: Which of These Thermostat Settings Costs You More?

Have you ever looked at your thermostat and thought, “What is the difference between the ‘On’ and ‘Auto’ fan setting anyway? And which one should I keep the thermostat set to?”

If you haven’t, you should.

Because one of these fan settings can increase your electrical bill every month and lower the lifespan of your heating/cooling system.
Let’s explain.

The difference between On vs. Auto: 

These settings tell your central cooling/heating system when to use the blower. The blower is the part in your system’s inside unit (usually in your attic) that circulates cooled/heated air in your home

When “On” is selected the blower works continuously—24/7. This means that it’s always circulating air.  It does not matter if the air is being cooled or heated.

When “Auto” is selected the blower runs only when the system needs to cool or heat your home. As soon as the thermostat reaches the selected temperature, the blower turns off with the rest of your heating/cooling system.

So now this question comes: Which fan setting should you set your thermostat to?

While “On” has its uses, it’s best to leave your thermostat to “Auto”. Here’s why.

Why does the “On” setting cost you?

Since “On” causes the blower to run continuously, it can increase your electrical bill by about $8 a month (almost $100 a year), depending on the size of your system.

This continuous use also wears down the blower which will shorten its lifespan and increases the chances it will break down and need repairing.

Of course, we can help you if that ever happens. But we’re sure you would want that to happen later rather than sooner.

When in doubt, leave your thermostat to “Auto”!

Want to save even more each month?

Looking for more ways to save money?

Check out our other articles:

  • 3 Quick Tips for Buying the Right Programmable Thermostat
  • 4 Reasons Your A/C Is Needlessly Skyrocketing Your Utility Bills
  • Why Closing Air Vents in Unused Rooms Damages Your Heating/Cooling System

Cool Guys has been keeping San Antonio-area homes comfortable and energy efficient since 2011. Contact us online for more information about any of our services

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