A water heating system and an intake and exhaust system thereof

P10479.AU Specification final - 18/08/2021 - 12 An intake and exhaust system for supplying air to and venting a water heating system, comprising: (a) an intake duct which, in use, is in fluid communication with water heaters 5 and configured to intake air from the atmosphere via an intake end of the duct and supply it to the heaters; and (b) an exhaust duct which, in use, is in fluid communication with the heaters and configured to vent exhaust from the heaters to the atmosphere via an exhaust end of the exhaust duct; 10 wherein at least the intake and exhaust ends of the respective ducts form part of a single intake and exhaust unit, the unit being configured such that, in use, it extends through a roof or wall of a building structure serviced by the hot water system and into the atmosphere and both intakes air for supply to the heaters and vents exhaust therefrom. r'J I.-L r'4J r-4-