How Does a Wax Thermostatic Element Works?

by | Apr 26, 2022 | HVAC

wax thermostatic element how it works, manufacturer


When the weather is hot, people want their rooms to be colder. It will make the air becomes fresher. And when the weather is cold, people want their room to be warmer. So, we don’t get influenza because of it. Of course, every people want to make themselves to be comfortable. That is why the tools are here. The tools can set your room temperature to become warmer or colder as you want. The wax thermostatic element is the answer to your problem. Before you buy this, you better know to answer the question: how does a wax thermostatic element work?

What Is Thermostat?

A thermostat is a tool that keeps the temperature well. In other words, it means that the thermostat is to maintain the temperature. It is different from temperature. Temperature is a tool to measure the temperature, not maintain it. The thermostat itself comes from the ancient Greek language. Thermo means heat, and status means standing. From the name, we know that thermostat is a tool to maintain the temperature in your room. 

How Does a Wax Thermostatic Element Work?

Wax thermostatic element use thermal expansion to do its work. What is thermal expansion? Thermal expansion means utilizing the principle that when something is heating, it will be bigger, and when something is cooling, it will be smaller. This is called a mechanical thermostat. It is used to turn on and turn off the power of the thermostat. 

Before we describe how does a wax thermostatic element works, you need to know two common types usually used by wax thermostatic elements. 

Strips Of bimetallic

The traditional thermostat uses strips or bimetallic, and it works as a bridge to connect the electricity. When the strip is down, it brings the electricity to the circuit, and the heating becomes in on mode. 

When the room becomes cold, the strip becomes cold too, and it will be back to its original size. The electricity will flow again, and the snaps will be back. And it will make the switches on. If the thermostatic element uses bimetallic strips, it will take longer. This happens because it takes a longer time for the metal strip to contract and expand. The heating doesn’t directly appear in on mode or off mode, just in a few seconds. But it takes an hour or more to be in starting position again. It depends on how cold or hot the weather is outside, how insulated your room is, etc.

This time, people use gas-filled bellows. What is it? Let’s describe this type below!

Gas-Filled Bellow

If using strips of bimetallic will take a long time to be heated or cold again, it will be different in using gas-filled bellow. 

Gas filled-bellow is in a pair of metal discs. The metal discs are large, which makes the response faster than using strips or bimetallic. It is more flexible. The gas below will expand when the room is warmer. It forces the discs to become apart. The inside discs will push a micro switch in the center of the thermostat becomes off. 

On the other hand, the gas in the metal discs is forced when the room is cold. The inside discs move from the micro switch, and it will turn on the heating up again. Furthermore, gas-filled bellow is more flexible and faster in time than strips or bimetallic. Now, let’s describe how does a wax element thermostatic works?

How does a wax thermostatic element work?

From the explanation above, mechanical thermostats use substances that convert the size or shape with higher temperatures. Strips of bimetallic expand the metal when they get hotter; from the other point of view, gas-filled bellow uses gas when they get hotter. Some thermostats will change the state of a substance. It is from liquid to gas. 

Thermostats use wax inside a sealed chamber. As the temperature becomes changes, the wax will be melted. It changes from solid to liquid. It will expand bigger and then pushes the rod of the chamber. After that, it will become in power mode on or off. That is all about how a wax thermostatic element works. With knowing the answer, you will believe how important a thermostat is in your home. It is used in your air conditioner, in your bath up, and so on.

Besides, the wax thermostatic element’s principle is applied in shipping, plumbing, sanitary, military, cooling engine systems, radiator valves, car engines, and so on. So, it is beneficial for you.