You may have temperature control on a wall in your home to manage the heating system. That is your thermostat, a contemporary term derived from two ancient Greek words Thermo and Statos . The thermostat has a floating mercury thermometer connected to a damper lid on a furnace. When the thermometer's mercury reaches a specific level, the float shifts, forcing the damper to close. Despite its simplicity, the first thermometer paved the way for modern thermostats. Modern thermostats perform the same function but with a lot more technology. The thermostat of today is a heat-activated switch with a temperature sensor. This switch opens and shuts, completing or interrupting the electrical circuit responsible for heating and cooling with the help of HVAC duct access doors . Let us examine the components of a thermostat to see how it works! Mercury This liquid metal conducts electricity and flows in the same way as water does— through three wires within a glass vial. The wire runs the w...