What Temperature Should I Set My Thermostat? Expert Recommendations

Finding the right thermostat setting balances comfort with energy efficiency. In Tucson's extreme climate, the right settings can save hundreds of dollars annually while keeping you comfortable.

Recommended Settings for Cooling Season

When Home and Awake: 78°F

The Department of Energy recommends 78°F as the ideal summer setting. This temperature:

• Provides comfortable cooling for most people
• Keeps energy use reasonable
• Allows your AC to cycle normally
• Balances comfort and cost

When Asleep: 78-82°F

Your body temperature naturally drops during sleep, so slightly warmer settings often feel comfortable:

• Most people sleep well at 78-80°F
• Use ceiling fans for additional comfort
• Lightweight bedding helps
• Programmable thermostats automate this adjustment

When Away: 85°F or Higher

Raising the temperature when nobody is home saves significant energy:

• 85°F reduces cooling demand substantially
• Smart thermostats can cool before you return
• Consider going even higher for extended absences
• Never turn AC completely off in summer (humidity and heat damage)

Recommended Settings for Heating Season

When Home and Awake: 68°F

For winter heating in Tucson:

• 68°F is comfortable for most while keeping costs manageable
• Wear warmer clothing if needed
• Use blankets rather than raising temperature

When Asleep: 62-65°F

Cooler sleeping temperatures are often preferred:

• Many people sleep better in cooler rooms
• Use warm bedding instead of higher thermostat settings
• Significant energy savings overnight

When Away: 55-60°F

During absences:

• 55°F prevents any risk of pipe freezing
• 60°F if away for extended periods with plants or pets
• Avoid turning heat completely off

Energy Savings by Temperature

Every degree matters for your energy bill:

Cooling Setting	Approximate Cost Impact
74°F	+12% vs 78°F
76°F	+6% vs 78°F
78°F	Baseline
80°F	-6% vs 78°F
82°F	-12% vs 78°F

On a $300 summer electric bill, the difference between 74°F and 78°F is about $36/month.

Tips for Comfort at Higher Settings

Use Ceiling Fans

Ceiling fans create a wind-chill effect that makes 78°F feel like 74°F:

• Run counterclockwise in summer
• Turn off when leaving the room
• Fans cool people, not rooms

Block Solar Heat

Reducing heat gain lets you stay comfortable at higher settings:

• Close blinds on sun-facing windows
• Use reflective window treatments
• Consider exterior shading

Dress Appropriately

Light, breathable clothing makes higher temperatures comfortable:

• Cotton and linen fabrics
• Loose-fitting clothes
• Light colors

Stay Hydrated

Proper hydration helps your body regulate temperature more effectively.

Common Thermostat Mistakes

Setting Temperature Too Low

Setting the thermostat to 68°F won't cool your home faster—your AC cools at the same rate regardless. You'll just overshoot and waste energy.

Constant Manual Adjustments

Frequent adjustments waste energy and reduce comfort. Use programmable features for consistent, efficient operation.

Closing Vents in Unused Rooms

This increases duct pressure, reduces efficiency, and can damage your system. Keep all vents open.

Ignoring Programmable Features

Modern thermostats can automate temperature adjustments. Set it once and let it work for you.

Smart Thermostat Benefits

Upgrading to a smart thermostat can save 10-15% on heating and cooling:

Features Include:

• Learning your schedule and preferences
• Remote control via smartphone
• Energy usage tracking
• Geofencing (adjusts when you leave/return)
• Integration with smart home systems

Popular Options:

• Nest Learning Thermostat
• Ecobee with room sensors
• Honeywell Home T-series

Arizona-Specific Considerations

Extreme Heat Days

When temperatures exceed 110°F:

• Your AC can only maintain about 20-25°F below outdoor temperature
• Pre-cool your home in the morning
• Be flexible with temperature expectations
• Ensure system is well-maintained

Monsoon Season

Higher humidity during monsoons affects comfort:

• Lower settings may be needed to manage humidity
• Ensure your AC is removing moisture properly
• Consider a dehumidifier for problem areas

Finding Your Personal Comfort Zone

Everyone's comfort preferences differ. Find yours by:

1. Starting at recommended settings (78°F summer, 68°F winter)
2. Living with that setting for a week
3. Adjusting by 1 degree if uncomfortable
4. Giving each adjustment several days before changing again
5. Noting impact on energy bills

Need Help Optimizing Your System?

If you're struggling to maintain comfortable temperatures efficiently, your HVAC system may need attention. Intelligent Design can evaluate your system and recommend improvements.

Call (520) 333-2665 for expert advice. We've been helping Tucson homeowners stay comfortable since 1979.