VRF systems are well adaptable, especially when it comes to replacing old chillers. Tariq al Ghussein, chairman and CEO, Taqeef, says that chiller replacement in high rise buildings is where highest capex and opex can be realised.
Ghussein lists down a few points to consider before undertaking a retrofitting project:
1 Ensure an audit is performed to inspect the status of the existing system by examining current heat load and energy analysis based on the previous energy bills. The VRF system selection is optimised and a lifecycle cost analysis is made to assess the retrofit feasibility.
2 Prepare a proposal that considers the physical constraints in the facility along with suggested timelines designed for minimum disturbance to the tenants. It is recommended to kick-off with the retrofit process at the beginning of the low load season in November.
3 The preparation work needs to start before removing the existing system and the piping plan should be considered before discontinuing the old system in order to reduce down-time.
4 Finally, once the retrofit project is complete, an accredited measurement and verification firm should be assigned to validate the energy savings achieved against the agreed benchmark.
Talking about the compatibility of VRF systems with connectivity and technology, Ghussein says: “IoT and automation are the new frontiers in advancing the HVAC-R sector, and VRF is at the helm of this paradigm shift. Our Energy Solutions Division specialises in smart control innovation and installation and we see this as a key growth area. Today, most VRF systems can be interfaced to a ‘Smart Home Automation’ system by means of adapters/converters, which allows them to connect to the various communication protocols, such as BMS/Modbus, LonWorks, KNX etc. Multi VRF systems can be linked to centralised controllers allowing advanced monitoring and diagnostics of complete facilities from a single location.
“Additionally, VRF troubleshooting applications can be made available on your smart phone (I-phone or Android) to allow remote system access.”
The advantage of VRF is its energy consumption at partial load, which is not reflected in the current regulations/ratings. Ghussein adds that the UAE government could further encourage the use of smart and high efficiency systems such as VRFs, by reducing or eliminating taxes/duties on systems exceeding a reference benchmark in energy efficiency. He says: “If the current MEPS (Minimum Energy Performance Standards) were modified to incorporate the partial load performance of the equipment (such as ISO 16358; which considers the cooling seasonal performance factor, a standard that accurately reflects the real partial load at different temperatures) instead of simply following the traditional SEER standard or limiting it to the peak load performance (which usually constitutes no more than 10 % of the complete operating spectrum) this would further highlight VRF’s benefits and encourage use. The main advantage of the VRF system lies in the energy savings at partial load operation, but presently the local MEPS solely considers the peak load operation. However, less frequent peak load cycles should still be considered when designing a power plant in order to avoid electrical shortages or machinery breakdown during fully functional periods.”
On Taqeefs plans in the Middle East, Ghussein says: “We’re continuing to build our portfolio of VRF projects – which already includes a 5,000 VRF villa project - while we increasingly adapt IOT to technology to further enhance performance.”