Mitsubishi Heavy Industries Air-Conditioning & Refrigeration Corporation (MHI-AC&R) has developed a “compact” ultra-low-temperature (ULT) nitrogen (R728) indirect brine chiller, providing temperatures from −100 to −40°C (−148 to −40°F).
Expected applications for the new N-Bleath unit include process cooling and storage in the chemical, medical, pharmaceutical and semiconductor industries, as well as environmental testing in the aerospace and automotive sectors, according to the manufacturer. The company plans to begin sales of N-Bleath in Japan in April 2027, with units currently undergoing pilot studies, MHI told NaturalRefrigerants.com.
“N-Bleath utilizes air-cycle refrigerant technology, with a proprietary system (patent pending) providing exceptional load-following capability,” said MHI-AC&R. “It is equipped with a newly developed compact electric turbo [compressor] from MHI Engine & Turbocharger, enabling product miniaturization and high efficiency.”
The specifications: The N-Bleath unit uses an inverter drive system and will be available in three models across two modular sizes: The smaller-capacity model measures 1,860 × 1,110 × 1,844mm (73 × 48 × 73in), and the two larger-capacity models measure 4,940 × 2,317 × 2,800mm (195 × 91 × 110in).
- The A45-LTS-B model covers the entire −100 to −40°C temperature range, providing 8kW (2.3TR) of cooling capacity at a brine temperature of −60°C (−76°F) and 7kW (2TR) at −80°C (−112°F).
- N80-LTS-C covers a temperature range from −70 to −45°C (−94 to −49°F), providing a cooling capacity of 31.5kW (8.9TR) at a brine temperature of −70°C.
- N110-LTS-C covers a temperature range from −100 to −65°C (−148 to −85°F), providing 23.3kW (6.6TR) of cooling capacity at a brine temperature of −100°C.

New component: The compact electric turbo compressor, developed using aerodynamic technologies, uses a high-speed rotating impeller to compress the nitrogen refrigerant, according to MHI-AC&R.
- The design supports cooling below −100°C. After compression, the refrigerant is cooled in a heat exchanger and then expanded, reducing its temperature to the ULT range, MHI explained.
- In addition, the compressor uses oil-free bearings, which reduces maintenance requirements, the company added.
Other news: MHI recently installed a 90kW (25.5TR) CO2 (R744) air-source heat pump to provide domestic hot water for an Adagio Hotel in London.
- The system comprises three MHI Q-ton ESA30EH-25 units, paired with five 1,000L (264gal) storage tanks.
- It supplies water at up to 75°C (167°F) for the 140-room hotel, operating in ambient temperatures as low as −25°C (−13°F).
Quotable: “Going forward, MHI Group will promote the widespread adoption of cooling systems utilizing PFAS [per- and polyfluoroalkyl substances]-free natural refrigerants with ODP [ozone depletion potential] and GWP factors of zero,” the company said. “N-Bleath is one of the products aligned with [this] growth strategy. We believe it will significantly accelerate the industry’s progress toward carbon neutrality.”
“Going forward, MHI Group will promote the widespread adoption of cooling systems utilizing PFAS-free natural refrigerants with ODP and GWP factors of zero.”
MHI-AC&R



