How Does a Water Heater Work?

Are you deciding whether you should install a water heater in your home? Water heaters provide many benefits, from comfortable showers to easy laundry. But how exactly does it do that?

Here’s a brief explanation to answer the question, “How does a water heater work?” Let’s start!

How a Water Heater Operates

Generally, hot water starts with water traveling from the main water line before you can use it in your home. Once it reaches your water heater, it splits into two ways that make up your property’s entire water system.

When you activate the hot water tap, cold water goes into the water heater tank through the dip tube. The heating mechanism keeps the tank warm according to the thermostat setting.

So, cold water starts to warm once it arrives. Note that if you already have hot water in the tank, it rises while the new cold water sinks. When the hot water is ready, it comes out of the tap by passing through the heat-out pipe.

Heating in a Gas Water Heater

The traditional water heater usually uses gas as the heating element to warm the tank. With the gas burner, it could produce hot and toxic air. So, it usually comes with a chimney to release it.

Heating in an Electric Water Heater

An electric water heater works almost like a gas water heater but uses a different heating element. Moreover, it has a thermostat, allowing you to adjust the temperature of the tank.

Heating in a Tankless Water Heater

With a tankless water heater, it takes away the need for water heating and storage. Instead, it focuses on providing hot water only when needed.

So unless you open the hot water tap, it won’t heat water. And so it saves energy, reduces leaks, and regulates the hot water supply according to the demand. 

Water Heater Components

When learning how a water heater works, you should know its parts. This way, you can visualize how it uses each component and provide you with newly warmed water.

The parts are as follows:


Most types of water heaters store hot water inside insulated tanks. It comes in different sizes, varying on the capacity you need to supply your home.

Dip Tube

The dip tube is where cold water passes to enter the tank from a supply or different source. It’s usually located at the top of the tank and brings in cool water there.

Heating Mechanism

Every water heater comes with a heating mechanism, regardless of the type. It’s usually either a gas burner or an electric element.


You usually find thermostats only in electric water heaters. It allows you to control and maintain the tank’s temperature. You can check more about the features of water heating and storage solutions here.


Water heaters come with three types of valves. The drain valve drains out built-up sediment and brings it outside, a shut-off valve turns off water flow, and a pressure relief valve regulates the tank’s pressure levels.

Heat-Out Pipe

The heat-out pipe is the opposite of the dip tube since you can find it at the top. It directs hot water to the tap.

Knowing More on How Does a Water Heater Work

When you think, how does a water heater work? It’s good to learn the operation of different types of heaters. This way, you can find an option that fits your needs the best.

Check out our blog to learn more about them!