RACA Journal August 2023 | Page 37

Project

R22 design consisting of some ( 62 OFF ) floor-standing , self-contained ducted packaged units located in plantrooms throughout the building . Close circuit cooling towers ( 11 OFF ) at roof level , provided the means of heat rejection .

After some 24 years of operation and several successful attempts at extending the life of the equipment , the airconditioning plant was eventually deemed no longer economically viable to retain . This decision was further influenced by the need for energy conservation as well as environmental considerations .

Following an extensive feasibility study which included in-depth site surveys , equipment selection and a small prototype chilled water installation , a presentation to the owners was conducted on 26 August 2016 . The proposal was duly agreed upon and the services of RPM Consulting Engineers appointed accordingly . Design commenced in earnest , the contract documentation and drawings being

“

IT ALWAYS SEEMS

IMPOSSIBLE

UNTIL IT ’ S DONE .

- Nelson Mandela

issued to the relevant contractors at a pre-tender meeting held on 19 June 2017 .

DESIGN AND INSTALLATION It was subsequently agreed that the original water-cooled packaged unit arrangement would be replaced with a chilled water system . Air-cooled chilled water generators located within the existing cooling tower plantrooms at high level , would provide the necessary cooling to ( 62 OFF ) bespoke chilled water air handling units . The units would be housed in the existing packaged-unit plantrooms located on the floors throughout the building .

Control would be by way of the upgrading and re-programming of the existing Building Management System ( BMS ).

RPM Consulting Engineers

Existing condenser water pipe making way for new chiller modules .

RPM Consulting Engineers

Bespoke CHW air-handling units being installed within existing plantrooms . www . refrigerationandaircon . co . za RACA Journal I August 2023 35