January 29, 2026
When your heating or cooling system won’t turn on, the thermostat is often the first place to check. While some thermostat issues are simple fixes, others can point to a bigger HVAC problem. Here’s how to tell the difference.
Common Reasons a Thermostat Stops Working
Dead batteries
This is the most common issue. If your thermostat screen is blank or unresponsive, try replacing the batteries first.
Incorrect settings
Make sure the thermostat is set to the correct mode (Heat or Cool) and that the temperature is set higher or lower than the current room temperature.
Tripped breaker or power issue
Some thermostats are powered by your HVAC system. A tripped breaker or blown fuse can shut it down completely.
Loose or damaged wiring
Over time, wiring behind the thermostat can come loose or wear out, especially in older homes.
Dirty or outdated thermostat
Dust buildup inside the thermostat can affect performance. Older models may also struggle to communicate properly with newer HVAC systems.
Signs It’s More Than the Thermostat
- ● Your system turns on and off randomly
- ● The temperature doesn’t match what’s on the screen
- ● Heating or cooling runs nonstop
- ● No response even after changing batteries
These can point to issues with the furnace, AC unit, control board, or sensors.
What You Can Try Before Calling a Pro
- ● Replace the batteries
- ● Double-check settings
- ● Reset the thermostat (if applicable)
- ● Check your breaker panel
If none of these work, it’s best to stop troubleshooting and have a professional take a look.
When to Call an HVAC Technician
Enhance your home’s comfort and efficiency with our professional humidifier and dehumidifier services. Contact All Around Cooling & Heating today to schedule a consultation or service appointment. Our team is ready to assist you with all your HVAC needs in Cottonwood Heights, UT, and the surrounding areas.
Invest in your home’s comfort and efficiency with All Around Cooling & Heating—your trusted HVAC partner.
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