MHI Develops "ETI-Z Series" of Next-generation Centrifugal Chillers

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.