Many Sydney houses or units built in the 1950’s or 1960’s will have a gravity feed electric storage tank inside the roof space.
These hot water heaters usually have a very long lifespan of 30-40 years, as they don’t operate under mains pressure. For this reason they have very few problems, but do have low water pressure. These types of hot water heaters require a special style of shower rose to achieve maximum performance.
A lot of gravity feed systems are reaching the end of their life now. You can replace them with the same style of hot water heater or with a mains pressure electric hot water system or gas hot water system in another location. As all the pipework and electrics are already in the roof, this can be a very economical and environmentally friendly option. A Heat Pump hot water system is another alternative.