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PROJECT
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2
3
1.
2.
3.
4.
Circulation pumps ensure
the hot water reticulation
system can produce
hot water at any outlet
quickly and also eliminate
dead leg sections.
The air heat pump
installation.
Each section of the
hospital has a kitchenette
with a hydroboil unit.
Some of the drainage
pipes needed to be
galvanised due to the
chemical composition
and high temperatures of
some of the discarded
liquids that can reach in
excess of 120°C.
The building re-development project started in May
2018 and is scheduled to be handed over at the end
of May 2019.
The design specification from the client was to use five
of the existing nine floors at the Hospital Group’s Head
Office in the Johannesburg’s central business district, to
construct a new day hospital which will have three new
surgical theatres, a new radiology department, as well as
two floors of doctors' consulting rooms.
COLD WATER SYSTEM
The wet services design is based on a gravity fed
system, starting with the storage tank on the rooftop of
the building. From this tank, water is fed down to the
floors below where the reticulation is fed via the water
network to the relevant sanitary points on the floors.
Due to the existing building being nine stories high,
the water pressure build-up from the tank down to the
various floors creates adequate pressure to sufficiently
feed all water points. This eliminates the need for a
pressure booster pump and reduces the reliance on any
July 2019 Volume 25 I Number 5
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mechanical failure and water interruptions.
Pipe sizing was crucial to make sure the flow to all points
was sufficient, and was designed by Amaré Schütte,
Mechanical Engineer of IX Engineers.
HOT WATER SYSTEM
The hot water system installed is based on the
same principle of the cold water, beginning at roof
top tank and reticulating to the plant room on the
first floor of the building. Cold water is fed into the
600ℓ hot water cylinder that is integrated with two
alliance air heat pumps. The water is preheated
in the plant room system before being fed to the
various floors of the hospital. To ensure hot water
on demand, 200ℓ Kwikot geysers are installed on
each floor of the new hospital.
On each floor, two Grundfos hot water circulation pumps
have been installed. These pumps are controlled via
a control panel and ensure that pumps operate at
maximum efficiency as well as notifying the maintenance
team should there be any error with the pumps. The hot
water circulating pumps’ main function is to circulate hot
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