Reported hot water system failure

Some central hot water systems can fail after as little as 8 years of what seems normal service.

The equipment was only 8 years old when water began leaking into the unit below...






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Left: One of the pump installations

The hot water system uses gas fired Rheem Ray Pak domestic hot water service heaters and Grundfos in-line circulating pumps configured into two blocks each with two heater units and two pumps, which, with associated storage tanks, serve a total of 164 unit.

The equipment was only 8 years old when the failure occurred.











Left: The paper-thin metal that that remained in the elbow, where a pinhole leak was revealed

Above, left and right:The bright copper interiors of the eroded pipes. The eroded bend which revealed a similar leak in the pump suction bend was replaced and tested.

Expert advice was that the velocity of the water being circulated by the in-line pumps was so high that cavitation in the water itself was eroding the copper bends and system pipe connections.

Plant maintained by Simon Waugh of Canberra Boilers.

Alan Christie took the pictures – Contact him on 6282 0007 for more details