Project
A new central exhaust system is installed for the apartment laundry and bin exhaust . The system comprises a new exhaust fan on level 30 , and new exhaust ducting extending to level 10 .
A sustainable feature of this air-conditioning system is that it does not consume any water to reject heat ( no cooling towers are used ), which is a criterion highly regarded by the GBCSA .
The chilled and heating water systems are closed-loop systems . Fresh water is a delicate commodity that should be treated with care . In future , it will become even more of a critical factor to consider in the design of air-condition system solutions . Also , the additional benefit from not using cooling towers for heat rejection is that there is no chance for Legionella bacteria to form .
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Pieter de Bod | WSP
Revit modelling of the ground floor chiller plant room .
The four new hermetic scroll R410 air-cooled chillers were carefully selected and controlled to allow either chilled water generation or heating water generation , or both at any given time . Each chiller offers over 300kW of cooling or 340kW of heating , two refrigeration circuits and an on-board primary pump . The refrigerant has an Ozone Depletion Potential ( ODP ) of 0 .
© RACA Journal | Benjamin Brits
PROJECT CHALLENGES The design team was confronted with numerous design challenges and constraints . It is not a trivial task to design a basement ventilation system for an existing building . Several basement ventilation design strategies were studied during the concept design stage , but the strategy that involved the least amount of structural and financial implications was chosen .
3 " Fresh water is a delicate commodity that should be
treated with care . In future , it will become even more of a critical factor to consider in the design of air-condition system solutions ."
Careful coordination with the structural engineer and architect was necessary to ensure the execution of a successful basement ventilation system . It is always imperative to make sure that the intake and exhaust positions are a sufficient distance apart from each other to minimise the effect of air short circuiting or cross contamination .
www . hvacronline . co . za RACA Journal I October 2021 33