Electric hot water cylinders are the most common form of hot water heating system found in New Zealand. These consist of an insulated cylinder tank usually made from copper, stainless steel or vitreous enamel-lined steel.

Cold water enters the tank and is then heated by an electric element controlled by a thermostat to a temperature above 60oC. When hot water is required throughout the house, the hot water is drawn from the top of the tank. It is then replaced with cold water at the bottom to be heated back to temperature.

The most common sizes of electric hot water cylinders are 135 litres or 180 litres for standard households and 250l and 300l cylinders for larger homes.

Electric hot water cylinders can be configured for mains-pressure or low-pressure setups depending on the cylinder type and hot water valves used based on household requirements.

Learn more about electric hot water cylinders here.