Like many commercial refrigeration original equipment manufacturers (OEMs), the transition to lower-global warming potential (GWP) refrigerants had long been on FBD’s product development radar. As a leading manufacturer of frozen beverage dispensers — such as those used by major restaurant and convenience store chains, theme parks and beverage brands — FBD began evaluating its lower-GWP refrigerant options in 2017, from its headquarters in San Antonio, Texas. 

Its leadership recognized early on that a phasedown of hydrofluorocarbon (HFC) refrigerants was imminent. And with many of its customers beginning to set more aggressive sustainability goals, FBD was eager to stay ahead of the coming changes. 

Since then, its product development efforts have focused on migrating to lower-GWP refrigerants — without impacting its familiar equipment footprint or strict performance standards. Their goal was to ensure that any internal product design changes would be transparent to their existing customer base.

As a long-time Copeland customer, FBD’s research and development (R&D) team partnered with Copeland engineering in 2018 and 2019 to support them through their refrigerant migrations. FBD’s leadership empowered the R&D team to leverage the collaboration and take a ground-up approach to system redesigns.

Cameron Crandall, managing director of R&D at FBD, said new equipment prototypes were built on a foundation of Copeland’s proven next-gen scroll compressor platforms.

“It was important for us to align with the direction Copeland was already moving and develop a new design strategy around that,” he said. 

After keeping a close eye on the refrigerant landscape and trends impacting commercial refrigeration design, Crandall said that the R&D team began formalizing its short- and long-term refrigerant transition in 2019. As a first, intermediate step, they converted its units to the lower-GWP A1 R-448A. 

FBD’s long-terms plans were focused on migrating to refrigerants below 150 GWP. This decision required evaluating and testing all available refrigerant alternatives and optimized compression technology, which ultimately led to the selection of R-290 (aka propane).

Navigating the Refrigerant Landscape and its Impacts on Equipment Design

Staying up to date on dynamic global, federal and state refrigerant regulations has not been an easy task for commercial refrigeration stakeholders — and FBD was no exception. The refrigerant transition places additional strain on OEMs, who must initiate product design cycles to achieve domestic and global compliance and certification.

As FBD began this journey in 2019, it was unclear what the next generation of refrigerants would be. 

Phase one of FBD’s transition started with a known lower-GWP option, R-448A — an A1 HFC refrigerant with very familiar characteristics. But with even lower GWP limits expected in the not-so-distant future, the R&D team set out to select its next-gen refrigerant strategy that could mitigate regulatory uncertainties.

It was important to minimize the burden that comes from going through multiple refrigerant transitions over a short period of time. 

“Each refrigerant transition consumes our resources, not only from a design cycle, but also the efforts needed to support it. The more model variants in the market, the more confusion it creates for our install base and service providers,” Crandall said.

Preparations for phase two of the refrigerant transition required closer inspections of emerging and available alternatives. CO2 was gaining acceptance in centralized systems but had yet to scale into smaller, stand-alone units. 

R-290 had already been widely used in low-charge, self-contained applications. Classified as a flammable (A3) refrigerant, R-290 has long been approved for use by the Environmental Protection Agency (EPA) and requisite safety standards — which had mandated a 150-gram charge limit. Recent updates to the UL 60335-2-89, 2nd edition (2022) safety standard support increased charge limits. EPA approval of this charge limit increase is still pending, while building code updates are underway in various state and local jurisdictions. Regardless, R-290’s A3 classification introduced new design considerations.

A2L refrigerants were another emerging class of lower-GWP, lower-flammability refrigerants were included in the UL 60335-2-89, 2nd edition standard. A2Ls were new to the commercial refrigeration sector and had yet to be approved for use by the EPA. Still, they represented potential for higher charges than R-290 in self-contained equipment.

With R-290 and A2Ls as their primary options, FBD set out to learn everything they could about working with flammable refrigerants. The R&D team was careful to follow all international and U.S. safety requirements in their designs, including participation in one of the Underwriters Laboratories (UL) working groups supporting its standard updates.

As the team explored the availability of R-290 and A2L-optimized compressor platforms, the Copeland scroll platform was preferred for its reliability and track record of success in FBD designs. And with their wide global adoption in existing self-contained, refrigeration applications, Copeland R-290 scrolls offered a proven path forward.

Regardless of the refrigerant choice, Crandall said that a key safety mitigation measure was to minimize the refrigerant charge while ensuring they were able to meet FBD unit capacity requirements. Flammability aside, the new refrigerant alternatives had unique thermodynamic properties and characteristics that impacted product design, efficiency and capacity. 

The R&D team’s overarching goal was to maintain a similar case design with robust dispensing performance that its customers would expect. This meant using a single-circuit, single-compressor condenser and proprietary multi-evaporator design to keep its familiar equipment footprint and meet performance requirements. 

Development of Product Prototypes

FBD collaborated with Copeland to align compressor platforms with its next-gen refrigerant selections, and then moved forward on new product prototypes. The R&D team selected R-290 as its primary option and the A2L R-455A as an alternate.

Even though the two refrigerant options have different properties, they also require similar mitigation measures — which started with keeping charges as low as possible.

The team moved forward with a standardized design that was multi-refrigerant compatible for R-290 and R-455A. Compressor selection was based on specifying a frame size and displacement that would achieve the unit’s output and/or production requirements, i.e., cooling/freezing capabilities and drink production volume.

Having used a Copeland ZB scroll compressor for its previous generation of HFC units — as well as the Copeland ZS*KAE for its R-448A unit conversions — the team was excited to select another Copeland scroll, the YS*KAU, for its new R-290 prototypes. 

The compressor selection enabled the team to maintain its single-circuit, multi-evaporator design principle. Offering 1–4 HP, the Copeland YS*KAU R-290 scroll compressor achieved the necessary capacities while keeping R-290 refrigerant charges well below the allowances set forth in the latest safety standards. 

To minimize any impacts to customers, these internal condensing unit design changes would be completely transparent. Prototypes are currently being tested for safety and certification compliance for use with their chosen A3 and A2L refrigerant options, Crandall said.

Preliminary Test Results, Preparing for Launch

Compared to an equivalent R-448 base model, FBD’s ground-up, redesigned R-290 prototype has demonstrated impressive performance metrics:

• 11% reduction in discharge temperatures. 
• 17% reduction in current draw.
• Reduced compression ratios from 9:1 to 7:1.
• More than 10% increase in the coefficient of performance (COP).
• 30% reduction in discharge pressures.

“This has allowed our organization to rally around a refrigerant strategy, compressor frame size and displacement that offers a nicely balanced and flexible solution,” Crandall said. 

FBD will begin compliance testing in 2024, while making multiple sample units available for customer training and demos. A limited launch is expected in 2025, with the official launch of the R-290 optimized product family tentatively set for 2026.