Press Information

MHI Develops "ETI-Z Series" of Next-generation Centrifugal Chillers
-- Adopt New Non-ozone-depleting Refrigerant to Minimize Greenhouse Gas Emissions --


Tokyo, June 10, 2015 - Mitsubishi Heavy Industries, Ltd. (MHI) has developed a new series of centrifugal chillers, dubbed the "ETI-Z Series," adopting a new refrigerant, HFO-1233zd(E), that offers outstanding environmental compatibility. The various models in the new series will be progressively launched starting this September. The ETI-Z series marks the world's first small-size centrifugal chillers to adopt the new refrigerant.

The ETI-Z Series carries on the fundamental product concept of the ETI Series: high performance combined with compact size. The ETI series with built-in inverter panel have been widely spread in to the market since the first models were introduced in 2008.

Models in the new ETI-Z Series have a cooling capacity within a range of 80 to 700 refrigeration tons*1 (RT). Superlative performance is achieved by reducing motor drive-energy loss through the adoption of a compressor with high-speed direct motor drive, the elimination of step-up gear and use of fewer bearings. Together these features enable achievement of a rated COP (coefficient of performance)*2 of 6.7 in the 200 RT class. Reliability has also been enhanced through structural simplification.

HFO-1233zd(E) features the same low global warming potential (GWP)*3 as carbon dioxide (CO2), i.e. 1, and an ozone depletion potential (ODP) of 0. Owing to this minimal impact in terms of greenhouse gas emissions and no impact vis-à-vis ozone depletion, the new refrigerant is not subject to Japan’s Freon Emissions Control Law*4. This means that HFO-1233zd(E) is not regulated in terms of curbing emissions or leakages, recovery and destruction for disposal, etc. Compared to MHI’s current refrigerant*5, however, the volume of refrigerant gas is about 5 times greater, therefore to achieve the same capacity, generally the size of the compressor and heat exchanger will be increased. In the ETI-Z Series, a more compact size has been realized by applying the latest blade shape, increasing the motor speed, and by adopting and optimizing the arrangement of the high-performance tubes.

The microcomputerized control panel features a new board that enables more precise control, thanks to increased speed of the central processing unit (CPU), to support the energy-saving operation of the chiller. The adoption of a touch panel type liquid-crystal display both enhances operability while also improving functions that support maintenance of the main unit. Going forward, MHI plans to enhance its lineup of centrifugal chillers featuring the new refrigerant by progressively developing and launching models up to the 1,500 RT class, including fixed-speed models.

MHI is Japan’s leading manufacturer of centrifugal chillers, with cumulative orders for its high-efficiency chillers topping 3,000 units since 2000. The company’s chillers are acclaimed worldwide for their outstanding efficiency and reliability. In the years ahead, MHI will develop its accumulated technologies in this area even further, dedicating its resources to the development of products that can continue to contribute significantly to energy savings and environmental protection while simultaneously responding to the market’s needs.

*1) Refrigeration ton represents the refrigerating capacity for turning 2000 lb of 0°C water into 0°C ice in 24 hours. 1 RT = 3,024 Kcal/hr.
*2) Coefficient of performance (COP) indicates the ratio of a system's useful energy output versus the system's energy input. The higher a system's COP, the higher is its energy-saving efficiency. In the case of refrigeration systems, COP = rated cooling capacity (kW) / electricity consumption (kW).The cited value was calculated based on Air-Conditioning, Heating and Refrigeration Institute(AHRI)
*3) CO2 is assigned a GWP of 1. The lower the GWP factor, the less impact on the environment.
*4) This new law, which took effect on April 1, 2015, stipulates rules for the rational use and proper management of fluorocarbons.
*5) HFC-134a

About MHI Group

Mitsubishi Heavy Industries (MHI) Group is one of the world’s leading industrial groups, spanning energy, smart infrastructure, industrial machinery, aerospace and defense. MHI Group combines cutting-edge technology with deep experience to deliver innovative, integrated solutions that help to realize a carbon neutral world, improve the quality of life and ensure a safer world. For more information, please visit or follow our insights and stories on