thermostat
temperature regulator / thermal control valve
Noun
pl: thermostats
This term describes a mechanism of feedback control designed to maintain a specific thermal equilibrium. It is most commonly associated with domestic HVAC systems, where it acts as the interface between the user and the heating or cooling hardware. In automotive contexts, the word refers to a mechanical valve that manages coolant circulation. This specific application is critical for engine efficiency, as it prevents the motor from running too cold or overheating.