Are VRF efficiencies in line with regulation? In terms of SEER, what are VRFs able to achieve? 

VRF units, under ESMA 2019 regulations, have been regulated to maintain Minimum Efficiency Requirements, based on CSPF (Cooling Seasonal Performance Factor) under ISO 16358-1:2013/AMD 1:2019 standard. Depending on capacity Class, VRF units are mandated to have CSPF above 12.5 – 14.0 Btu/h/Watt. Speaking of General and Midea VRF units, they are able to meet – even exceed – these Minimum Efficiency Requirements. 

Has the VRF industry reconciled with the need for validated operational data that would reflect the true measure of energy efficiency of VRF systems? 

The VRF industry has made strides towards reconciling with the need for validated operational data to accurately measure the energy efficiency of the VRF systems. However, the process is ongoing, and there are several key aspects to consider. Standardisation and testing protocols by local regulatory authorities, like ESMA, ADQCC and Barjeel, currently do make sure that the VRF units available for use in the UAE are in line with the Minimum Efficiency Requirements. While significant progress has been made, challenges remain with validating operational data that would reflect the true measure of energy efficiency of VRF systems. There isa need for more comprehensive and widespread data collection from a variety of real-world installations, as well as continuous improvement in testing methodologies to keep pace with technological advancements.The industry continues to work towards achieving a balance between laboratory-tested performance and actual operational efficiency to provide a true measure of the energy efficiency of VRF systems. 

How has workmanship progressed in terms of proper installation of VRF systems, including piping, to prevent leakage of refrigerants? For instance, improper brazing is still prevalent. What is Taqeef doing, in particular to train the technicians?

VRF units are technologically advanced air conditioning systems, which require experts in installation, testing and commissioning to utilise the full potential of the technology. Taqeef ensures that installers of VRF units are trained to install them in line with manufacturers’ recommendation and to follow best installation practices at site. Taqeef also ensures the installation quality by frequent site visits at every stage of equipment installation of the project. In addition to these, the inhouse projects operation team in the company undertakes testing and commissioning of the VRF units to ensure trouble-free operation. With these measures, we are able to narrow down on-site issues, like refrigerant leaks and improper brazing at early stages of installation and to rectify them at the earliest possible opportunity. 

Are new routes opening up for expansion of VRF applications? For instance, in high-rise buildings? For instance, is there better collaboration with architects and the need for dead spaces in high-rises for installation of outdoor units?

New routes are opening up for the expansion of Variable Refrigerant Flow (VRF) applications, including in high-rise buildings. The main limitations for VRF units are the total piping length, the vertical piping length and the communication wiring lengths. Currently, VRF units proposed by Taqeef can support up to 1,000 metres of total refrigerant piping network; up to 110 metres of vertical piping between the outdoor and indoor unit, which is about 30 floors; and transmission wiring and are able to perform efficiently to the varying loads for FAHUs, which operate throughout the year with different ambient conditions. As per ASHRAE 62.1 standard for ventilation system design and acceptable Indoor Air Quality (IAQ), and also as per Local regulatory requirements, like DMGBR (Dubai Municipality Green Building Regulations), there are minimum requirements for ventilation and fresh air, which vary based on the application. For UAE, since the ambient conditions are extreme throughout the year and conditions range from high dry bulb temperatures and high RH conditions during summer to Low Dry Bulb Temperature during winter, it is difficult for a constant-speed vapour compression system to cater to this load. In these conditions, VRF systems excel, as these units can modulate the cooling capacity output, thanks to variable- speed compressor, variable-speed condenser fans and EEVs.