PROJECT
INCORPORATING COLD CHAIN
“ It was a pleasure working with the following companies : Plennegy , our client ; WFW Steel Works , who assisted with all structural work and fitment of insulated room panels ; Dalucon . our supplier and manufacturer of the of chiller / freezer room ; Daikin , our supplier of the ZEAS condensing units ; Advance Electrical , who were responsible for the electrical panels ; Keystar , the supplier of the control system ; and Colcab for the evaporator coils .
PROJECT CHALLENGES The project commenced in September 2022 - when Simon Pride gave the go ahead - and completed 16 March 2023 . Commissioning is currently underway . While the project went ahead smoothly , there were a number of challenges to be faced : The first was a substantial two-year waiting period on the project , derived primarily from the delayed clearance from the US-based holding company of the client . This in turn delayed plan approval from council . The second was more local in nature : the challenge of establishing a reliable and adequate source of electricity , which is under investigation at the moment to supplement with solar energy . A third was excessive rain which hindered work .
Frank Butler and Ernest Hoddinott of WFW Engineering were involved on the project ’ s structural work from the outset . Hoddinott says : “ Corteva is a seed distributor , so the basis for the cold room was the need to keep the temperature of the warehoused seed stock controlled at a range near 10 ° C and humidity conditions above 45 % for extended periods of time . Maintaining the ideal RH is essential to prevent germination or spoilage . To achieve these precise parameters , meters for dehumidification have been integrated into the design . RH refers to the amount of moisture present in the air compared to its saturation point .
“ The warehouse building itself came with the challenge of requiring an enormous amount of backfill soil , approximately 7 000m 3 , to get the site level ,” he adds .
The cold room incorporates 14 Daikin condensers and Munters dehumidification plant with an impressive array of 40 Colcab evaporator coils inside the room . These components were carefully selected to meet the project ' s objectives , which was primarily optimal energy efficiency , says Bloom .
“ Daikin is well-versed in European refrigeration projects which is why we opted to collaborate with experts in the field to ensure the project ' s success .” Daikin , as a key collaborator in the project , has played a significant role in providing essential equipment . Their expertise lies in offering customised solutions tailored to specific applications .
“ The cold room comprises seven condensing units , of which six are slightly bigger than the last one and are interconnected with three evaporator coils each inside the facility . This arrangement results in a total of 18 evaporators and the last two evaporator coils on the one side are a mirror image configuration working off the smaller , seventh evaporator . This ensures efficient cooling throughout the space , while a smaller condenser unit complements the overall system .”
As a result of the energy debacle , the project ' s anticipated operational timeline remains a subject of discussion and the warehouse is still being commissioned . “ As of now , its current status is not yet at full operational capacity . However , diligent efforts are underway to ensure a successful completion ,” says Bloom .
BUILDING MANAGEMENT SYSTEM ( BMS ) Marcus Lefawane , the on-site service engineer for Daikin ’ s condensers , ensures the proper functioning and maintenance of the cold room . He explains that the BMS screen shows what each unit is doing , its current temperature and defrosting schedule .
Colcab ’ s coils are an essential feature of the cold room project to optimise performance and functionality . Daikin also provided the IP unit which facilitates communication between Keystar BTX 600 Building Management System and the refrigeration units . By providing an IP interface , they enable the units to communicate seamlessly with the customer ' s preferred BACnet Modbus BMS system .
The integration of the BMS with the refrigeration units offers facility managers invaluable information to monitor and control the cold room ' s operations . The BMS presents various data points , allowing managers to gain real-time insights into the unit ' s performance . This includes temperature differentials , unit statuses , defrost cycles , and more .
Automation plays a vital role in the cold room ' s functionality . When the temperature deviates from the desired
Left to right : Ernest Hoddinott , structural consulting engineer of WFW Engineering ; Graham Bloom , owner of Cool Reaction and project manager ; Marcus Lefawane , the on-site service engineer for Daikin ’ s condensers .
A nearby field , the typical destination of seeds . range , the units are programmed to initiate protective measures , such as defrost cycles , to safeguard the stored goods . This automation reduces the need for constant manual intervention , ensuring smooth and uninterrupted operations .
DAIKIN ZEAS OUTDOOR REFRIGERATION CONDENSING UNITS Michael Olivier : Daikin South Africa service engineer says : “ Daikin was approached by Graham Bloom from Cool Reaction for a refrigeration solution for a cold storage facility , the requirement being for an energy efficient modular system that has full monitoring capability .
“ Graham has previously used the Daikin VRV equipment and was looking to trial the refrigeration version of the tried and tested technology . The cooling load was to be spread across 40 evaporators wherein Daikin equipment selection and layout was done by consulting sales engineer Nico Van Heerden ; it was decided to match up the 40 evaporators to the Daikin ZEAS refrigeration condensers . The following equipment was used : 12 x LREQ20BY1 and 2 x LREQ12BY1 . Controls and monitoring were done using Eliwell equipment supplied by Keystar ,” says Olivier .
“ Each of the systems can be individually controlled both in the facility and remotely giving the client both peace of mind and total control over its facility . Daikin and Keystar assisted Cool Reaction with the commissioning of the site and was successfully completed .”
What is unique about the project , is that the cold facility has not been installed inside a warehouse - the roof and side walls are polyurethane injected chromodek .
Designed with its signature VRV technology and inverter technology , Daikin ZEAS condensing units cut energy consumption by 10 to 35 % when compared to traditional refrigeration systems . In certain instances , it even surpasses the 35 % saving , says Olivier . “ Combined with our economiser technology , ZEAS condensing units are more efficient , last longer and perform at a higher capacity than other solutions on the market ,” he claims .
” ZEAS units are factory-assembled and its reduced footprint makes installation in small spaces easy . Its modular design maximises installation flexibility because you can group outdoor units in blocks or rows , or rather distribute them around the building based on your needs . The built-in controls and automated optimisation features allow you to install a ZEAS unit as a plug-and-play solution . With the best surface-to-capacity ratio on the market , it also provides you with enormous savings in terms of space .
“ A big thank you to Graham and his team for successfully completing and commissioning the installation , the installation was of high quality and the commissioning process was a breeze . Looking very forward to many more projects with him and his team ,” says Olivier .
THE RTX 600 V DOMINO ZERO Ben Milne , WC Manager : Keystar Industries | Eliwell by Schneider Electric , says : “ Using the latest RTX 600 V Domino Zero to control the 40 evaporator PWM valves servicing this very large cold room space , we are able to obtain precise superheat and temperature control - allowing for stable suction conditions back to the Daikin ZEAS units .
“ Hand in hand , it is an excellent combination of electronic modulation , between evaporator and compressor . Aimed at achieving a perfect balance , it respects the safeties of the compressor to ensure its longevity while achieving pinpoint temperature control ,” says Milne .
“ RTX 600 V Domino Zero Electronic Expansion valve control has about 50 configurable parameter settings and options purely dedicated to fine tuning the valve control for the above purpose - should one of the eight pre-set cabinet / room default programme applications need adjustment .
“ On top of a vast variety of defrosting options on RTX , the temperature alarm functionality is also flexible , to suit any application . It is critical to ensure that the product is protected and watched over , should a failure occur . All 40 RTX controllers are linked back to the TelevisGo monitoring system , keeping eyes on every section of the room .”
Milne explains that TelevisGo is monitoring about 20 different alarm conditions from each RTX , and with its
24 www . coldlinkafrica . co . za COLD LINK AFRICA • July / August 2023