When summer hits Surprise, Arizona, and outdoor temperatures climb past 110°F, your air conditioner becomes the most important appliance in your home. It’s also usually responsible for the largest portion of your summer electric bill!
A common question we hear at Pro Solutions Air Conditioning and Heating Inc. is: “Is it cheaper to leave my AC at one temperature all day, or should I adjust the thermostat when I leave?”
The short answer? No, keeping your AC set to one constant, low temperature all day is generally not cheaper. However, in our intense West Valley heat, the full answer is a bit more nuanced. Let’s break down how thermodynamics, Arizona energy rates, and your thermostat work together so you can keep your home cool without overpaying on your utility bills!
Why does keeping the AC at one temperature cost more?
Many homeowners believe that letting the house warm up while they are away forces the air conditioner to work “harder” to cool it back down, consuming more energy in the long run. In reality, heat transfers into your home faster when the temperature difference between inside and outside is larger.
- High Temperature Difference: If you keep your thermostat locked at 72°F while it’s 115°F in Surprise, heat rapidly penetrates your walls, windows, and attic. Your unit cycles on and off continuously all day to fight that heat gain.
- Smaller Temperature Difference: If you let the thermostat rise to 80°F or 82°F while you’re out, the heat transfer slows down. Your system runs less overall during the hottest daytime hours.
According to the U.S. Department of Energy, setting your thermostat 7 to 10 degrees higher for 8 hours a day can save you up to 10% a year on cooling costs.
How does the Surprise, Arizona climate change the rules?
In milder climates, turning off the AC completely during the workday is common practice. But here in Surprise, turning your unit completely off in July or August is not recommended.
If your home’s internal temperature shoots up to 90°F or higher while you’re at work, your furniture, walls, and flooring heat up too. When you turn the AC back on, the system has to run nonstop for hours to remove that heat, putting immense strain on your compressor and capacitor.
The Ideal Arizona “Setback Strategy”
Instead of shutting the system off entirely, practice a moderate setback:
- When you’re home: Set your thermostat to a comfortable level (e.g., 78°F).
- When you’re away: Raise the setting by 4°F to 7°F (e.g., 82°F–85°F).
- When sleeping: Drop it slightly or use ceiling fans to create a wind-chill effect without overworking the AC.
Should I adjust my thermostat during peak electricity hours?
If your home is powered by APS (Arizona Public Service) or another local utility with Time-of-Use plans, electricity is significantly more expensive during peak afternoon hours (typically 4:00 PM to 7:00 PM).
To maximize savings:
- Pre-cool your home: Set the thermostat a few degrees cooler before peak hours start while electricity is cheaper.
- Nudge it up during peak hours: Bump the thermostat up to 80°F–82°F during peak hours so your system doesn’t run heavily when rates are highest.
What temperature should I set my thermostat in the summer?
Here are a few quick rule-of-thumb settings for Surprise homeowners trying to balance energy efficiency and comfort:
| Scenario | Recommended Thermostat Setting |
| At Home & Active | 78°F (Pair with ceiling fans running counterclockwise) |
| Away from Home (4+ Hours) | 82°F–85°F |
| Sleeping | 75°F–77°F |
| Vacation / Extended Travel | 85°F (Keeps humidity and heat low enough to protect home materials) |
Will a smart thermostat save money on my electric bill?
Yes! Upgrading to a smart or programmable thermostat (like Nest, Ecobee, or Honeywell) takes the guesswork out of daily temperature adjustments. You can set a schedule that automatically raises the temperature when you leave for work and cools the house back down right before you arrive home.
4 Additional Tips to Lower Your AC Bills in Surprise, AZ
Adjusting your thermostat is just one piece of the puzzle. To get the best performance from your cooling system:
- Change Air Filters Regularly: In dusty Arizona, air filters should be checked monthly. Clean filters improve airflow and lower energy consumption.
- Use Ceiling Fans Wisely: Fans cool people, not rooms! Turn them on when you’re in the room to make 78°F feel like 74°F, and turn them off when you leave.
- Block the Afternoon Sun: Keep blinds, drapes, or solar shades closed on west-facing windows to prevent direct heat gain.
- Schedule Annual Maintenance: An unmaintained AC unit loses efficiency every year, forcing it to run longer to reach the same temperature.
Keep Your AC Running Efficiently with Pro Solutions Air Conditioning and Heating Inc.
Finding the right balance between comfort and lower energy bills shouldn’t be a guessing game. If your air conditioner is struggling to keep up, running continuously, or causing unexpectedly high energy bills, our experienced team is here to help!
Whether you need a seasonal AC tune-up, a smart thermostat installation, or expert repair services in Surprise and the West Valley, contact Pro Solutions Air Conditioning and Heating Inc. at 623-232-8425 today!