3 thermostat mistakes that are costing you extra money this summer!

It’s summer and all kinds of fun (and costly) activities are calling your name: social outings, the water park, weekend getaways…

But you’re sitting at home looking at your utility bill thinking your summer budget just got tighter.

Sound like a situation you want to avoid?

Let’s start by addressing the 3 AC thermostat mistakes you could be making right now that are costing you extra money:

  1. Leaving your fan set to ON
  2. Not adjusting your thermostat before leaving the house
  3. Turning your AC off when you’re not home

If you’re guilty of any of these, read on for our easy, money-saving solutions…

Mistake #1: Leaving your fan set to ON

Your AC fan sits inside the air handler (your AC’s inside unit) and blows air through the air ducts and into your home. There are 2 fan settings to choose from: ON and AUTO.

Setting your fan to ON means that the fan runs continuously—even when your AC isn’t actually blowing out cold air.

And a fan that runs constantly means higher energy and AC repair bills.


Your AC fan uses about 300 watts of electricity. At 10 cents per kwH,you can expect to add around $22 in electricity costs each month if you run your fan non-stop (24 hours/day). That’s over $260 worth of electricity per year!

Running your AC fan 24/7 also means you’re making your AC equipment work overtime. And this can result in more repairs and a shorter AC lifespan.

The money-saving solution?

Set your fan to AUTO.

The AUTO setting only runs your fan while your AC is blowing cold air. This cuts down on electricity costs and keeps your equipment running longer.

Another way this setting saves you money is by dehumidifying your home and keeping you dry and cool at lower temperatures than the ON setting.


The ON setting doesn’t remove humidity, making you feel warm and sticky. And what’s the first thing we do when we feel uncomfortably warm?

Turn down the temperature (which increases our monthly bill).

Mistake #2: Turning off your AC when you leave the house

Many homeowners believe that if they turn off their AC when they leave the house for the day, they’re saving money on electricity costs.

But when you turn your AC off you aren’t just dealing with high temperatures, you’re also dealing with high indoor humidity.

And high indoor humidity can cause expensive damage like:

  • Mold
  • Peeling paint
  • Warped wood
  • Failed electronics

The money-saving solution?

Turn up the temperature. (Again, a programmable thermostat can do this for you)

Ideally, you want to raise the temperature anywhere between 83-86 degrees when you leave the house for the day. This ensures that your AC is still dehumidifying your home throughout the day, saving you money on repairs.

Mistake #3: Not adjusting your thermostat when you leave the house

Let’s say you leave your house every day around 8:30 am and don’t return until 5:30 pm. And you don’t adjust your thermostat before leaving.

That means your air conditioner is working hard to maintain a comfortable temperature for 8 hours…and no one is home to enjoy it.

That’s a waste of money.

The money-saving solution?

Invest in a programmable thermostat.

According to the Department of Energy, you can save 10% or more a year just by turning your thermostat down 7 to 10 degrees for 8 hours a day.

But most people have 2 problems with this:

  • They forget to set back their thermostat every day
  • They don’t want to come home to a hot, stuffy house

Programmable thermostats solve both of these problems. These advanced thermostats can be pre-set to turn down the temperature at certain times throughout the day.

Let’s use the first example: if you leave your home at 8:30 am and don’t return home until 5:30 pm, you can program your thermostat to increase the temperature by 10 degrees at 8:30 am but return to your desired temperature at 5 pm.

This allows you to save money on electricity but also means you’ll never have to sacrifice your comfort since the thermostat switches to a cooler temperature before you get home.
Looking for a programmable thermostat that works best for your schedule but have some questions?

Need help installing it correctly?

We’re here to help. Contact us today for all your programmable thermostat needs.

Santa Fe Air Conditioning and Heating serves the Kansas City area.