Hot Water Cylinders Explained

woman taking a hot shower

Most people never really give much thought to how hot water cylinders and other water heating equipment work, all they really know is that when they get in the shower and turn the tap on the water comes out hot. There are a number of different systems and ways of heating water, including gas, solar and electric systems – gas and electric hot water cylinders are some of the most popular options out there and one of the most common systems that you’ll see in homes in Australia and New Zealand.

 

How hot water cylinders’ work

Hot water cylinders are a tank-based system that uses an electric element or gas burner to heat water. A thermostat will determine the temperature that the water is heated to. It’s a bit like the kettle you have at home, using an element immersed in the tank to heat the surrounding water. The system has two tubes, the first is a cold water tube that brings cold water into the tank and the second is a hot pipe that carries the hot water out to deliver it to your home.

In most cases, electric hot water cylinders are more efficient than their gas counterparts but tend to come at a higher cost and are slower to heat and recover than the gas tanks. Most gas hot water cylinders can heat approximately 190 liters in about an hour whilst an electric tank can take a number of hours.

 

Things to consider

worker setting up a hot water cylinder system at home

If you’re looking at buying a tank and thinking about whether you should go for gas or electric than you should keep in mind the fact that an electric system will likely come at a lower upfront cost and also offer slightly more flexibility, you can for instance connect them to solar or add a heat pump – this means you can make changes as your needs change or you family grows. You can also easily purchase a system that offers thermostatic control, this makes it easier to control cost and could save you a lot of money. If your tank is insulated the water will stay hot for several hours even after the element switches off. Most will even come with a timer which will allow you to take advantage of off-peak electricity hours.

The systems can usually be shut down simply by turning a switch on or off which can be very useful if you’re not going to be home. If you’re going away on holiday, save money by switching it off.

 

What should you be aware of when it comes to electric systems?

You will find that you pay a higher bill then if you’re using solar or gas power. Most electric systems will cost the average household about 78 cents per hour although the cost will vary depending on its capacity and the tariffs. The average household will need to heat water for at least a few hours during the day which means you’ll likely pay close to $600 annually for heating up your shower. Thermostatic control is also a must otherwise the temperature can get too high and it can end up becoming hazardous. It’s also very important to not set your thermostat too low, temperatures below 50 degrees Celsius can allow bacteria to survive and grow which could make your household sick.

The most important things to think about are your budget, needs, and space. Find a system that works for you and your household. Speak to an installation expert to find out what will be best for your long term needs and specific circumstances.