www . refrigerationandaircon . co . za RACA Journal I July 2023 35
Project
Hi Calibre Engineering ( Pty ) Ltd
The client ’ s brief was for the design and execution of the scope of work below :
• The installation of an Environmental Control System , necessary to maintain the 940m ² Warehouse 1 between 15 ° C and 25 ° C , and also to supply sufficient fresh air to comply with SANS requirements .
• The installation of a new independent Environmental Monitoring System to monitor and alarm when environmental conditions approach the upper and lower temperature limits for the facility .
• The EMS should provide live access to current temperature conditions as well as the ability to generate reports for any period , on any of the loggers .
• Remedial work to the interior walls , painting of the walls , remedial work to the floors and application of a self-levelling epoxy screed to a section , and installation of a new ‘ Lambda Board ’ ceiling for the entire extent of the warehouse .
• Removal of outdated fire suppression hardware and the revamp of the flammable store .
• The installation of a new roller shutter door , and integration of the controls into the biometric access system .
• Dust generation was to be kept to a minimum with no debris allowed to touch any of the packaged materials in the warehouse .
• Isles between racks and all walkways were to be kept clear during construction as normal factory operation needed to continue throughout the project , except for a December shut down when the floors were remedied .
THE HVAC / R SYSTEM ( S ) AND INSTALLATION The HVAC system comprises a 197kW air-cooled rooftop packaged unit that is of a split arrangement , to allow better positioning in a limited space . This unit is mounted outdoors on top of a newly cast concrete mezzanine structure and connected to rigid supply and return ducting that penetrates the building .
Inside the warehouse , the rigid supply ducting runs down the length of the warehouse with six fabric duct branches ranging from it . Each branch off has a static balancing damper that was set using a hot wire anemometer through a hole in the fabric ducting to determine the airflow . After the balancing damper is the VarioDuct fabric ducting supplied by FabricAir , the first such installation in South Africa . The VarioDuct consists of a rigid
www . refrigerationandaircon . co . za RACA Journal I July 2023 35