If you still don’t know the equipment, schneider electric already tell you: a thermostat is a component responsible for controlling devices, equipment, and circuits that deal with temperatures and their variations.

Because it is an instrumental piece for several sectors – industrial, commercial, residential, etc., it is already possible to find a great diversity of models for specific purposes of each area of ​​operation.

How Do Thermostats Work?

Regardless of which model, all components of this type have a similar function, consisting of detecting amplitudes of temperature variations and correcting them as an on / off switch. In addition, before we understand how they work, we need to understand which parts make up the system:

  • Sensors: responsible for capturing and monitoring variations that occur within the controlled system;
  • Regulators: as the name says, they make the thermal regulation by activating or shutting down the system automatically.

The joint action of these two mechanisms makes the thermostats function as automated regulators and as efficient control instruments, ideal for machinery and other equipment that depend on this need. For the proper functioning of the thermal controllers, the regulator is the central part since it gives the on/off command for compressors, coolers, air conditioning units, heaters, etc.

Analog Vs. Digital: Know The Differences

As we said earlier, there are some types of thermostats, but in general, they can be classified into two types: analog and digital. They differ in constitution and functioning.


It is the oldest model, but no less efficient thermostat. It works utilizing non-electronic sensors. In this case, this difference means that there are two main types of analog thermostats:


The sensors of this equipment are formed by two cast metal plates made of different materials. Due to the different thermal properties – especially the expansion coefficient – the different levels of expansion can be measured and analyzed by the device.

All of this happens because, when heated or cooled, the plates distort themselves in different directions, causing a loss of contact between them, which interrupts the flow of electrical current.

When this happens, the cooling/heating system is interrupted until the blades return to their original position.

  • GAS

Gas temperature sensors use the same principles as the previous model but with a different raw material. While bimetallic works from the expansion of metal parts, gas models work based on gas expansion.

In a bulb, usually metallic, a certain amount of an expandable gas is inserted. Thus, as the temperature increases and decreases, the constant volume inside the bulb causes the pressure to increase or decrease in the system. This measure is captured and interpreted by the regulator, who gives the necessary commands.


Another option within the universe of thermostats are digital models – these already have electronic sensors, such as thermocouples and thermistors, whose operation is based on a well-known property, electrical resistance.

The greater the movement within the system, the more excellent the resistance in the circuit, and vice versa. That done, there are not many differences between analog and digital: the regulatory part tries to receive and interpret the information collected by the sensors so that the system can be adjusted.

Application Areas: Where To Find Them

Now that you know everything about the properties of thermal regulators, it’s time to find out what the applications of these devices are in our daily lives. As you already know, it is very versatile equipment, with applications related to sectors ranging from industry to homes.

In the industrial area, thermostats are present in most machinery, as safety equipment, in case of overheating; on industrial scale appliances, such as ovens, refrigerators, and freezers;

In domestic and commercial environments, it is possible to find thermostats in the most diverse appliances and appliances: refrigerators, air conditioners, sandwich makers, microwaves, medical devices, and many others.

As these devices are specialized in temperature control, any device that requires this function will have at least one thermostat integrated into its circuit.