Feature
LATEST DEVELOPMENTS “ Every generation of VRF that is released will be improved by addressing limitations of the previous versions , but also specific to what markets require . This is achieved as new technology and methods evolve and can be anything from the improvement of the communication and control system to the incorporation of regionspecific safety measures .
“ An example of this is that South Africa is notorious for erratic power supply and load shedding , and so electronic components within our VRF range have been developed to address protection to minimising damage to units without any additional costs to the client . Another example is if an indoor unit is faulty , to limit the number of units that this affects – you obviously want to avoid a whole office sitting without their ACs working , or critical areas for that matter . Gree has implemented technology called CAN Communications Technology – where if an indoor or outdoor problem occurs , the technology automatically isolates the affected unit while the rest of the VRF system continues to operate without the building experiencing any interruptions . When it comes to heat recovery boxes , Gree has a range of 1 port , 2 ports , 4 ports and 8 ports . Our 4 port is driven by 2 PC boards , each driving two indoor units ; while our 8-port box is driven by 4 PC boards , each driving 2 indoor units . Such a design ensures minimal disruption to users within a building . We have also introduced a dual solar / grid VRF system – essentially meaning that you can run a system on whatever portion of solar PV energy you chose supplemented by grid power or on 100 % solar power ,” says Sibusiso Ndelu , Business Development Manager at Gree South Africa .
The pipelines on VRF systems are also astronomical elements . If you look at the total piping on a project , although there are limitations per system , they can reach kilometres . Suppliers today are also working on improving this capacity per system . Also being improved is the vertical differential between outdoor and indoor units .
“ Toshiba has just released their latest SMMS-u VRF system to the local market ( featured in this issue ) that has been recognised for a number of its features , most notably the improvements of the chassis design which is smaller but has increased capacity to 24HP through the implementation of a three-sided condenser design , and improved twin and world-first triple rotary compressor technology that further enables a diverse range of outputs and is customisable to exactly what clients need . Rotary compressors are known to provide better efficiency for part load operation . This is of particular value in today ’ s environment where many unique applications and the sensible heat load of buildings have also changed with the improvement and energy efficiency of other electronics and electrical appliances such as lighting .
“ We have also increased the compressor capacity to 120cc allowing longer pipe runs ( 1200m ) and increased vertical height differentials between indoor and outdoor units ( 110m ). We are also able to now offer the lowest capacity of 0.3 horsepower ( 0.84 kilowatts ) with this new system catering to smaller offices or meeting rooms . Also on the list of highlights is our intelligent control system that allows for variable operation and load distribution between indoor units thus increasing efficiency and user comfortability ,” says Beswent Bester , specifying engineer at AHI Carrier Toshiba SA .
Communication technology for some VRF brands has improved so that if something does go wrong , the fault can be isolated , and
20
RACA Journal I July 2021 www . hvacronline . co . za