
A couple of centuries ago, the idea of controlling the temperature of your environment would have sounded like sorcery. Today, it is a common, everyday occurrence made possible through the advent of thermostats. Traditional mechanical thermostats are fairly simple devices that contain: a mercury switch, a thermometer coil, a circuit board with mode switches, and two thermometers ' one that displays the current temperature and another inside that directs the heater or air conditioner to turn on or off. Thermostats are used for both natural gas and electric heating systems.
In these traditional thermostats, the mercury switch is connected to the internal thermometer and the circuit board. The thermometer is made of a coiled bimetallic strip that expands and unwinds or contracts and winds back according to the temperature. Simply put, as this coil expands and contracts it moves the switch, leaning it one way or the other to connect with a corresponding wire that relays to either the heater or the air conditioner. When the temperature levels off, the coil expands or contracts and causes the mercury switch to breaks its circuit with the wire. As a result, the heater or air conditioner turns off.
Today, digital thermostats are all the rage because you can more precisely control when the heater or air conditioner will turn on and how long it will run, thus conserving energy. See the articles below to find out more about thermostats.