What is the primary function of a thermostat in an HVAC system?

The primary function of a thermostat in an HVAC system is to control air temperature. A thermostat is a device that senses the temperature of the environment and regulates the heating or cooling equipment to maintain a desired setpoint temperature. When the temperature in a space falls below or rises above the setpoint, the thermostat signals the HVAC system to either turn on or off, ensuring a comfortable environment.

While measuring air temperature is an important aspect of how thermostats operate, that function alone does not define their primary role. Similarly, providing remote access is a feature of certain modern thermostats but is not a fundamental function of all thermostats. Additionally, sensing humidity levels, while relevant to some HVAC systems, is not the main purpose of a thermostat, which focuses specifically on managing temperature. Thus, controlling air temperature accurately reflects the essential role of a thermostat in maintaining indoor climate comfort.