24 PROJECT
All photos © Plumbing Africa Rory Macnamara
A refurb for Momentum Metropolitan Head Office
Edited by Rory Macnamara . Technical input by David Wills of WS-P Wet Service Consulting Engineers .
Situated in Die Howes , Centurion , the Head Office of Momentum has received a refurbishment which included the water and waste reticulation .
David Wills of Wills Franklin Pretorius was the design engineer for the plumbing contract , providing all design documentation and conducting the site inspections .
A rational design standard in accordance with SANS 10400 was followed due to the complexity of the building . As in any renovation of a building , locating services and connection to existing services was a challenge .
The cold-water reticulation is direct from the municipal supply . The existing system allowed for 500L / 1000L pressurised cold water storage tanks on the first floor .
In the event of a water outage , this storage water would drain down in the building ’ s ablutions via gravity with the assistance of air admittance valves . This system has been made redundant and new JoJo tanks have been supplied for borehole water .
Due to the borehole water quality , the raw water first needs to be treated . A small water treatment plant ( WTP ) has been installed .
This is fitted with fibre reinforced vessels with auto backwash heads , filled with activated filter media ( AFM ) then passes through granular activated carbon filters ( GAC ). The treated water is then sterilised by UV before being pumped into a treated water tank . A small set of multistage booster pumps were installed to boost this water through the building and is connected to the toilets and urinals only .
In the event of a power failure , a municipal bypass has been installed .
The hot water generation system for the main kitchen has been installed as a heat accumulator with an Alliance heat pump . Resistive immersion elements have also been installed to the tank as an emergency heating source . The hot water is circulated through a loop to maintain short waiting times at the fixtures .
www . plumbingafrica . co . za @ plumbingonline @ plumbingonline @ PlumbingAfricaOnline September 2022 Volume 28 I Number 7