Project into a common header towards the gas coolers and share common liquid receivers .
The maximum HVAC required capacity was for the January month at 1 493kwR , and the maximum thermal energy was 14 774kwhr to be shared equally by the ice tanks and HVAC / refrigeration packs with HVAC packs only operating if the internal load required them to operate .
A CO 2 detection system with alarm monitoring is installed in the plant room and on walk around freezer .
The ACS team researched the application of CO 2 for a few years prior to this project and especially in order to combine the HVAC requirements with the refrigeration requirements .
Previous , Makro projects used hydrofluorocarbon ( HFC ) refrigerants such as R134A for the HVAC installations and several stores were already using CO 2 for the refrigeration installations on low and medium temperature cold rooms and cabinets .
With the worldwide drive to combat global warming , ACS and Massmart decided to use CO 2 refrigerant which has a zero ODP and a GWP of merely 1 , for the combined chiller packs .
CO 2 is increasingly becoming the preferred refrigerant in many refrigeration installations with comparable coefficient of performance ( COP 2.8-3 ) with other refrigerants , but also a refrigerant that produces high temperatures thus making water heating a very viable solution .
Walk-around chillers complete .
The HVAC / refrigeration rack .
The system ’ s HVAC ice thermal tanks .
www . refrigerationandaircon . co . za RACA Journal I January 2023 37