How does a water heater work?

A water heater has now become an indispensable appliance in our everyday lives. Without a hot water tank, our morning showers would be a bit more… invigorating. There are many kinds of water heaters available on the market, gas or oil fired for instance, but the most common type in Quebec is the electric water heater. If you have a HydroSolution water heater, you might never have asked yourself how this device works because it comes with a turnkey service. Our models also come with superior insulation, a sturdy tank, and a drain valve made of brass instead of plastic for guaranteed peace of mind. But you might still be interested in knowing how a water heater works. The basic principle is simple. The device heats the water it contains which becomes lighter and rises to the top of the tank. This is known as stratification.

How a dual-element water heater works

It might seem like a complicated process, but the reality is that a water heater is a simple device once you understand stratification. Under pressure, the cold water enters either by the side, bottom, or top of the tank. It is then heated by the elements and because hot water is not as dense as cold water, it rises to the top. The hot water stays separate from the cold water, creating layers. Once you use hot water, located in the top of the tank, the pressure causes more cold water to enter the tank. Which is then heated again and the process begins anew. Thermostats installed on the top and bottom of the tank activate the elements if needed and maintain the water at the ideal temperature: between 60 et 65 o Celsius. Insulation around the tank keeps the water hot until it is ready for use.

The main components of an electric water heater

To better understand how an electric water heater works, here are the main components in a dual-element tank with a bottom cold water entry.

Tank: The inside of the tank is made of metal and includes a lining that protects it from the water.
Magnesium anode: The magnesium anode protects the tank from corrosion.
Cold water shut off valve: This allows you to manually shut the cold water supply if needed.
Dip tube: The water enters from this pipe located on top of the tank and drops to the bottom to be heated.
Elements: One is located in the top, the other in the bottom of the tank. They heat the water.
Thermostats: Thermostats control how hot the water becomes. There is usually one per element.
Relief valve: Water expands when heated and generates pressure. The relief valve allows the pressure to be released.
Expansion tank: The expansion tank absorbs the pressure variations due to the constant change in the volume of water. It also ensures the pressure stays the same in the tank.
Drain valve: This allows the water to be drained from the tank if you need to repair an element or move the appliance.

There are several advantages to owning an electric water heater. And the savings will add up. That’s why it’s important to choose yours in line with how much water your household needs and the source of energy available.