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PROJECT
1
Cold water is taken to only two of the three hot water tanks and tee into one 76 diameter pipe which then connects to the inlet of the third tank , supplying hot water to each floor via a main riser pipe . To ensure that hot water is circulated throughout the building , there are two hot water circulating pumps in duty and standby mode .
Circulation is done per floor and does not enter the apartments themselves due to hot water metering requirements . The hot water return flow is balanced using manual balancing valves per floor . The pump rotation is rotated weekly by the control system .
All hot water pipes are insulated according to SANS 10400 XA .
2
The cold-water storage tanks , in the event of a municipal water outage , consists of a 127m ³ sectional steel tank with three internal subdivisions located in basement level three . A vertical multistage booster pump set with expansion tank and Variable Speed Drives ( VSDs ) is installed .
The domestic water portion of the main tank is reserved at the top of all three sections and equates to approx . 50m ³ in total . The water is pumped via a constant speed booster pump set to two 21.73m ³ sectional tanks located on the ninth-floor roof .
These tanks are then connected to another vertical multistage booster pump set complete with expansion tanks and VSDs in basement level three to supply hot water and cold water to each floor of the building .
From the main cold-water riser in the plumbing duct , each floor is supplied by a ring main .
3
Heat pump system description The three domestic water-cooled heat pumps are supplied with on board cooled condensing system , scroll type hermetic compressors with built in electrical protection , silencer on the gas discharge line and crankcase heaters . These can operate in low ambient conditions from -15 ° C to 40 ° C and produce water to 60 ° C at an ambient of 7 ° C .
The heat pumps are a double circuit refrigerant system using R410A refrigerant . The distribution board houses all isolators for each heat pump .
Hydrant and hose reel installation Two hose reel and hydrant centrifugal single stage pumps have been placed in the basement level three service room . These function as duty and the other as stand by . The pumps draw water from the tank located in the basement level three , with 15m ³ of water reserved for
All images : © Plumbing Africa | Rory Macnamara
“ From the main cold-water riser in the plumbing duct , each floor is supplied by a ring main .”
1 . |
Building supply pumps . |
2 . |
Drainage sump controls . |
3 . |
Drainage and fire pipe configuration . |
www . plumbingafrica . co . za @ plumbingonline @ plumbingonline @ PlumbingAfricaOnline March 2022 Volume 28 I Number 1