What Is the Best Temperature for AC in Summer? Top Settings to Save in Las Vegas

The U.S. Department of Energy suggests setting your thermostat to 78 degrees Fahrenheit when you are home and need cooling, and higher when you are away. It also says you can save as much as 10 percent a year on heating and cooling by turning the thermostat back 7 to 10 degrees for 8 hours a day. In Las Vegas, a practical summer plan is 76 to 78 degrees when home, 80 to 85 when away and whatever lets you sleep well at night.

There is no single perfect number. Comfort, health and budget all matter. On a 115 degree afternoon, your system may not hold 72 anyway, and pushing it there mostly raises the bill.

What Are Good AC Settings for a Las Vegas Summer?

Do not turn the AC off in July

Shutting the AC off completely while you are at work lets the house heat soak. Walls, furniture and the attic absorb heat, and the system then runs for hours to recover. A moderate setback works better in the valley.

Why Not Set the AC to 70?

Because every degree lower costs more, and the system may not reach it. A system sized for Las Vegas is designed to hold a reasonable indoor temperature on a design day, not to hit 70 at 4 p.m. in July. If you set it far below what it can reach, it runs nonstop.

Watch for icing

Very low settings on cooler nights can also let the coil get too cold. See AC unit freezing up.

How Can You Feel Cooler at a Higher Setting?

Air movement and shade make 78 feel better.

• Ceiling fans. Run them counterclockwise in summer. Turn them off when you leave the room, since fans cool people, not rooms.
• Close blinds on west and south windows in the afternoon.
• Cook outside or use the microwave on hot evenings.
• Seal leaks around doors and windows.
• Keep the filter clean for full airflow. See how often you should change your AC filter.

Does a Smart Thermostat Help?

It can, if you set it up right. A smart or programmable thermostat can raise the temperature while you are away and bring it down before you get home. Pre cooling the house in the morning, before peak heat, can also help some homes.

Heat pump settings

If you have a heat pump, large setbacks in winter can trigger auxiliary heat when recovering. In summer, setbacks work the same as with an AC. See what is a heat pump.

What About Pets?

Pets left home need a safe temperature. Many owners keep the house at or below about 80 to 82 degrees for dogs and cats in summer. Older pets and short nosed breeds may need it cooler. Ask your vet.

What Should You Do If the House Will Not Cool to Your Setting?

If your AC cannot hold 78 on a normal summer day, something may be wrong.

1. Check the filter.
2. Make sure the outdoor coil is clean.
3. Check that vents are open and returns clear.
4. Look for ice on the copper lines.
5. Call for service if it still falls behind.

Our guide on why your AC is not blowing cold air covers each check.

How Much Can You Save by Raising the Temperature?

Savings depend on your home and habits. The Department of Energy estimate of up to 10 percent a year applies to setbacks of 7 to 10 degrees for 8 hours a day. For a deeper look at costs, read how much it costs to run AC.

A Typical Las Vegas Case: Turning the AC Off All Day

An owner turned the AC off before work to save money. By 5 p.m. the house was 92 degrees and the system ran until midnight to recover.

A setback to 82 degrees during the day kept the house from heat soaking. The system recovered within an hour of returning home, and the bill dropped.

Keep Your AC Ready for Summer in Las Vegas

A tuned system holds your setting with less effort. See our AC maintenance in Las Vegas page. If the house is too hot and someone is at risk, call our emergency AC repair line. West facing two-story homes in Summerlin often struggle most on summer afternoons. If yours cannot hold 78, see AC repair in Las Vegas.

Frequently Asked Questions

What is the best temperature for AC in summer?

The U.S. Department of Energy suggests 78 degrees when you are home and need cooling, and higher when you are away. Many Las Vegas homes use 76 to 78 degrees.

What should I set my AC to when I leave the house in Las Vegas?

Many homeowners set it to about 80 to 85 degrees when away. Avoid turning it off completely in summer so the house does not heat soak.

Is 72 degrees too low for AC in Las Vegas?

On very hot afternoons, many systems cannot hold 72 and will run nonstop. Setting it a few degrees higher saves energy.

What temperature should I set my AC at night?

Choose what helps you sleep, often 74 to 78 degrees. Ceiling fans help you feel cooler at a higher setting.

Does turning the AC off during the day save money in Las Vegas?

Usually a moderate setback saves more than turning it off. In extreme heat, a closed up house can heat soak and take hours to recover.

How much does each degree save on AC?

It varies. The Department of Energy says setbacks of 7 to 10 degrees for 8 hours a day can save as much as 10 percent a year on heating and cooling.

What temperature is safe for pets in summer?

Many owners keep the house at or below about 80 to 82 degrees for pets. Older pets and some breeds need it cooler. Ask your vet.

Why can my AC not keep up with my setting?

A dirty filter, a dirty outdoor coil, low refrigerant, leaky ducts or an undersized system can all cause it. Have it checked if it cannot hold 78 on a normal summer day.