What Are Mechanical Thermostats?

Mechanical thermostats are devices that control temperature through physical principles. They typically use mechanical elements such as bimetallic strips, liquid expansion, or gas expansion to sense temperature changes. When the temperature reaches a preset value, these elements trigger a switch action to control the activation or deactivation of heating or cooling devices. Mechanical thermostats are widely used in both residential and industrial settings for their durability, cost-effectiveness, and ease of maintenance.

How Do Mechanical Thermostats Work?

The temperature sensor in a mechanical thermostat, also known as a bi-metal thermostat, consists of two layers of metal bonded together. Each type of metal expands at a different rate when heated or cooled, which regulates the thermostat's temperature.

It’s important to note that mechanical thermostats function within a specified temperature range, meaning you are not selecting an exact temperature.

The manufacturer calibrates the thermostats in a testing laboratory, ensuring that the numbers displayed on the thermostat closely align with the actual room temperature. As a result, the temperature in your room will hover around your set point, but it can fluctuate by about five degrees above or below that point at any time.