Hussmann Expands CO₂ Line with First Outdoor Condensing Unit for Stores and Warehouses

U.S. OEM Hussmann, a subsidiary of Panasonic, announced on December 4 that it is expanding its transcritical CO₂ (R744) refrigeration system product offerings with the addition of its first CO₂ outdoor condensing unit (OCU) for medium-temperature or low-temperature applications in retail and warehouse applications, including store display cases.

The 4HP CO₂-based OCU is one of the first in the U.S. that can support remote food retail display cases, which are typically served by transcritical CO₂ racks and separate condensers or gas coolers. This is in contrast to Europe and Japan, where CO₂ condensing units are widely employed in retail stores, with parent company Panasonic as a major supplier.

In the U.S. CO₂ condensing units are being used for walk-in coolers, another application accommodated by the Hussmann OCU (in coolers of 3,000ft²/279m² or less); it can also support warehouse unit-cooler applications. In general the Hussmann unit is designed for “small and medium-sized retail floorplans,” including convenience stores, the company said, adding that “its compact design offers various installation configurations – providing flexibility in placement.”

“This our first release of a CO₂ condensing unit product [with] more sizes to come,” said Michael Lehtinen, Senior Product Leader, CO₂ Solutions at Bridgeton, Missouri-based Hussmann. In particular, Hussmann said it plans to introduce a 10HP model in 2025 to accommodate warehouse unit coolers and large walk-in coolers.

The new unit, part of Hussmann’s Evolve Technologies portfolio, can supply saturated suction temperatures (SST) from -40° to 23°F (-40 to -5°C) and can function effectively at ambient temperatures up to 113° F (45°C); its capacities range from 8,431 BTUH (2.47kW/0.7TR) at -40°F SST and 113°F ambient to 26,519BTUH (7.77kW/2.2TR) at 23°F SST and 80°F (27°C) ambient. With a two-stage variable-speed rotary compressor, variable-speed fans and “advanced” controls, the OCU “surpasses U.S. Department of Energy (DOE) energy standards,” the company added.

FMI preview

Hussmann previewed the OCU in September at its mobile showroom/training facility for natural refrigerant products at the 2024 Food Industry Association (FMI) Energy and Store Development Conference in Baltimore. Lehtinen noted there that the OCU is a commercialization of Panasonic’s CO₂ condensing unit under the Hussmann brand in North America. “Instead of reinventing it, the only changes we’ve made to the unit are those required for compliance with local voltages and frequencies,” he said, adding that Panasonic has 25,000 units already installed globally.

The new CO₂ OCU is particularly targeted to supporting expansions of existing supermarkets, supplementing existing racks, Lehtinen said at the FMI conference. While the condensing units are suitable for meeting the complete refrigeration needs of small outlets such as convenience stores, so far Hussmann has only “a few tire kickers” in that segment. The issue for those retailers is finding technicians who are familiar with maintaining CO₂ technology, he added.

But Gaku Shimada, General Manager of Panasonic’s Condensing Unit Engineering Department, said in October that he sees “significant opportunities” in the U.S. for CO₂ condensing units. “With Hussmann’s strong market presence and customer base, Hussmann and Panasonic are confident we can establish ourselves as a key player in the CO₂ space.”

Other OEMS that have introduced CO₂ condensing units for retail display cabinets in the U.S. include Hillphoenix and Zero Zone.

CO₂ OCU growth in Europe

 In Europe as of December 2023, 8,500 stores used transcritical CO₂ condensing units, along with 60,000 that employed transcritical CO₂ rack systems, according to ATMOsphere research.

In February Panasonic announced the launch of a new 20HP CO₂ outdoor condensing unit for the European market with applications for supermarkets and industrial process cooling. The 20HP unit extended the company’s range of 2HP, 4HP and 10HP CO₂ outdoor systems and offers support for food retail and process cooling applications, including chilled and low-temperature display cases, walk-in cold rooms, freezers and blast chillers.

Since Panasonic launched its 2HP CO₂ unit in Europe in 2017, the company has installed around 4,000 OCUs, with 1,000 installations in the past year, said Shimada. Much of this growth is due to a major order from a large international supermarket chain, which has driven a shift in Panasonic’s customer base, he added.

“As of early 2023, non-food installations made up around 40% of our CO₂ OCU sales [in Europe],” Shimada explained. “But over the past two years, that has shifted toward supermarkets, which now account for more than 50% of our sales.”

“Instead of reinventing it, the only changes we’ve made to the unit are those required for compliance with local voltages and frequencies.”

Michael Lehtinen, Senior Product Leader, CO₂ solutions, Hussmann

A key trend Panasonic has observed in the European refrigeration market is the shift from centralized rack systems to condensing units, said José Manuel Alves, Regional Director for the U.K., Republic of Ireland and Netherlands at Panasonic Heating and Cooling Solutions Europe, in October at the Chillventa trade show in Germany.

“We’re seeing increasing interest from customers moving away from racks to OCUs for several reasons,” explained Alves. “One significant factor is the complexity and cost of replacing an entire rack system. With our OCUs, facilities can take a phased approach to upgrades, allowing for a gradual, less disruptive transition.”

Additionally, “if one OCU experiences an issue, the others can maintain operations, minimizing downtime,” said Alves. “In contrast, a single breakdown in a centralized rack system can affect the entire facility. We also see an impact on insurance and liabilities, with a preference for modular units.”

Panasonic has installed the most outdoor CO₂ condensing units – more than 16,000 as of September 2023 – in Japan, its home market, where the majority of transcritical C0₂ systems are OCUs installed in convenience stores. Convenience store chain Lawson is by far the leading user of CO₂ OCUs, with more than one-third (5,300 stores out of 14,656) using them as of February 2023.