PROJECT 25 controlled at 60 ° C and once this set point is reached , the VSDs reduce the speed of the pump circulating water between the hot water storage tanks and heat exchangers . As the supply temperature to the building reduces , for example during high hot water demand periods , the VSDs increase the speed of the pump circulating water between the hot water storage tanks and heat exchangers . This increases the flow from the hot water tanks to the heat exchangers which in turn increases the energy available to heat the water supplied to the building .
2
Two hot water circulating pumps in duty and standby mode are used to circulate hot water throughout the building ensuring constant hot water . Circulation is achieved per hot water riser with thermostatic balancing valves installed on Residential level , one on each hot water return line before connecting to the main hot water return ring main on Parkade 2 .
The hot water circulation does not enter the apartments themselves due to hot water metering requirements . This is done by each apartment being fed from hot water ( copper ) and cold ( galvanised ) water pipe risers , nineteen ( 19 ) to each floor from the main ring on soffit of Parkade 2 . A service cupboard is allocated for the pressure reducing and metering stations on the outside of the apartment close to the kitchen . Inside the service cupboard is a valve , strainer , water meter , pressure reducing valve and valve for hot and cold-water pipes .
3
Hot water pipes are insulated with Armaflex or similar insulation if concealed in a ceiling void or plumbing duct and cladded with sheet metal in plant rooms .
1 . |
Gas safety shut off valve |
2 . |
Incoming gas and domestic water and Waste Pipe |
3 . |
Main hose reel and hydrant pump |
4 . |
Sprinkler pump room sump |
5 . |
Two Heat Exchangers |
4
1
5
April 2022 Volume 28 I Number 2 www . plumbingafrica . co . za