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

The primary function of a thermostat in an HVAC system is to maintain the desired temperature within a designated space. It accomplishes this by monitoring the current temperature and communicating with the heating or cooling system to either activate or deactivate based on the set temperature. When the ambient temperature deviates from the desired setting, the thermostat sends signals to the HVAC unit to adjust its operation—either heating or cooling the air to bring the environment back to the preferred level. This function is essential for ensuring comfort in residential and commercial settings, making temperature regulation one of the core purposes of a thermostat.

In contrast, measuring humidity levels, controlling the flow of refrigerant, or filtering the air are functions handled by different components within the HVAC system. Humidity control might involve separate humidistats or dehumidifiers, the flow of refrigerant is managed by the compressor and expansion valve, and air filtration is addressed by air filters within the system. Each of these elements plays a vital role in overall HVAC performance, but they do not encompass the thermostat's primary role of temperature management.