Project
to the building management system ( BMS ) via BACnet without any other interface . The pump can also be connected directly to the chiller via BACnet .
IMPACT OF THE SYSTEM ON ELECTRICAL USAGE The impact on electricity demand is minimal due to the design of the major HVAC equipment . All chillers , pumps and cooling towers were selected at the best coefficient of performance ( COP ) and “ VSD operation ” is already incorporated with the pump equipment to achieve high part load operation .
ODA Design and Drafting
A revit model of the MSSL pumps - 3D view .
fundamental difference in the Armstrong Design Envelop Pumps when used in an HVAC systems is the unique controller which incorporates embedded intelligence - thus eliminating the requirement for adding any variable speed drives ( VSDs ).
The pump requires no external input from a pressure differential sensor or a flow meter and completely does away with this requirement for the entire system , resulting in additional savings . The pump has its multi-speed curve and efficiencies pre-programmed into the controller and the embedded intelligence allows the pump to run sensorless , reacting to changes in the system instantaneously .
Furthermore , the pump displays pressure and flow rates on the controller and can feed this information directly through
ELEMENTS THAT MAKE THIS PROJECT SPECIAL / UNIQUE The chillers use natural HFO refrigerant thus reducing the global warming potential of the plant . The refrigerant used is R514A which has an ODP of 2 which is among the lowest in the industry . The use of the intelligent Armstrong circulating pumps in addition increases operational efficiency . These pumps can be easily incorporated into the cooling system , as they come with their own additive control logic . This software predicts the plant ’ s requirements at any given time , resulting in saving energy and running costs . RACA
" The impact on electricity demand is minimal due to the design of the major HVAC equipment ."
© RACA Journal | Benjamin Brits
Primary and secondary condenser water pumps located on the upper level of the plant room .
© RACA Journal | Benjamin Brits
This photo shows the new facility ( Phase 2 ) and to the right ( down the road ) is Phase 1 .
www . refrigerationandaircon . co . za RACA Journal I July 2022 33