In June, Mitsubishi Heavy Industries Thermal Systems, Ltd., a Group company of Mitsubishi Heavy Industries, Ltd. (MHI), will launch a new series of large-capacity centrifugal chillers adopting the CFC-free HFO-1234yf refrigerant having extremely low environmental impact: zero ozone depletion and a GWP below 1. The series will have two models: the constant-speed JHT-Y and the inverter-equipped JHT-YI.
Both new models feature capacities ranging from 300 to 5,400 refrigeration tons (RT), with the maximum capacity representing a 400 RT increase over the “GART-ZE/ZEI” series launched in 2017. The JHT-Y and JHT-YI are the first centrifugal chillers with capacities up to 5,400 RT offered commercially in Japan to feature a low-GWP refrigerant. Together with the “ETI-Z” series of centrifugal chillers in the small-to-medium capacity range launched in 2015, MHI Thermal Systems will now offer a full lineup of low-GWP refrigerant models in variations spanning from 150 to 5,400 RT.
The new series also adopts an all-new type of compressor. Increasing the variety of models enables selection of the optimal compressor to match the output of the chiller, to realize high performance throughout the capacity range. The constant-speed model features a rated COP of 6.9, which, as before, provides one of the world’s highest levels of energy efficiency together with compact size. Chillers in the new series can also be controlled with supreme precision using the latest microcomputer operation panel, and both the constant-speed and inverter models can respond to diverse applications including low-temperature, heat-pump and heat-recovery specifications.
The HFO-1234yf refrigerant, which is also used in car air conditioners and vending machines, has an ozone depletion potential (ODP) of zero, its atmospheric greenhouse effect being on a par with natural refrigerants. Because the HFO-1234yf results in no harmful emissions into the atmosphere, requires no capture after usage, and causes no degradation, it is not subject to Japan’s Revised Fluorocarbons Recovery and Destruction Law. This contrasts with equipment adopting high-GWP refrigerants – for example, HFC-134a, which was widely used before the revised legislation took effect; because such systems have significant adverse impact on global warming, laws now require reductions in both their production and usage volumes. As regulations on the marketing of equipment using high-GWP refrigerants will be tightened further starting in 2025 (in the domestic market), today demands are calling for early upgrading to systems adopting low-GWP refrigerants of the kind used in the new JHT-Y/JHT-YI series.