CO2 Unit Coolers Take Center Stage as R-22 Is Phased Out

Anyone who’s disposed of old refrigeration equipment lately realizes that ongoing governmental actions around the globe have prompted refrigerant-dependent industries, such as supermarkets, to seek alternatives to traditional refrigerants. And those industries are increasingly turning to CO2-based systems.

Bohn, a brand of Heatcraft Refrigeration Products, has responded to these needs with the introduction of a new line of CO2 unit coolers, available in various configurations to meet the specific needs of supermarkets. The product line was recently featured at the Food Marketing Institute’s (FMI) 2009 Energy and Technical Services Conference in Indian Wells, California.

Chlorofluorocarbons (CFCs) and hydro chlorofluorocarbons (HCFCs) cause significant damage to the environment due to their high global warming potential (GWP). While more companies are beginning to understand this is an unsustainable model, the global supermarket industry has been leading the way in preserving the environment with lower GWP refrigeration systems.

According to FMI, more than half of North American supermarkets have sustainability programs in place. As part of these programs, many supermarkets are taking a closer look at their refrigeration systems as a way to reduce the overall environmental impact of their stores. Heatcraft Refrigeration is partnering with the industry by offering alternative products such as the new CO2 unit coolers. These efforts help our customers address ethical concerns while continuing to support their core businesses.

More than a century ago, CO2 was a commonly used refrigerant – the first unit dates to 1866 – but the technology declined in popularity with the advent of synthetic refrigerants. By the late 1930s, freon (a synthetic refrigerant) had supplanted CO2, largely because it could operate at much lower pressures and required refrigeration components that were less expensive to fabricate. In the ensuing decades numerous CFCs and HCFCs have been developed and used in commercial refrigeration.

The Montreal Protocol banned CFCs in 1996 and set in place a phase-out schedule for HCFCs. Now, the government mandate that eliminated the use of refrigerants such as R-12 and R-502, is moving to ban HCFCs, including R-22, with the law calling for a 25% reduction in HCFC production by January 2010.

Most of the U.S. commercial refrigeration industry is moving toward hydro fluorocarbons (HFCs) such as R-404, R-507, R-410 and R-134. Those have zero ozone depletion potential (ODP) but high global warming potential (GWP). CO2 also has zero ODP but offers a distinctly more favorable GWP of 1, compared to 3,800 for R-404A.

While several approaches can be used to achieve the goal of reducing global warming, the benefits of using a CO2 refrigeration system are numerous. With a reduced compressor, smaller pipe size and low refrigerant charge, the new product line boasts a high volumetric capacity in which HFCs are eliminated or restricted to a machine room – resulting in reduced risk of system leaks that means a decrease in carbon emissions. CO2 costs also are currently 90% less than traditional refrigerants, helping stores achieve a significant savings. Finally, multiple studies cite the benefits of better temperature control as a result of smaller (and warmer) pipe temperatures and fewer braze joints; reduced installation cost and space savings achieved through smaller line sizes and less copper piping; and the projected potential for energy savings.

Heatcraft Refrigeration’s new line of CO2 unit coolers includes 62 models – in low profile, medium profile, center mount and low velocity product families – all with selected features that are tailored specifically to the needs voiced by the supermarket industry. Capacities match standard direct expansion (DX) models and are measured in BTUH. Models designed for use with CO2 are configured for low-temperature DX or medium-temperature liquid overfeed/recirculation. As part of the E Solutions™ portfolio of environmentally friendly products, CO2 unit coolers join Heatcraft Refrigeration’s EC motors and glycol unit coolers in demonstrating the company’s continuing commitment to providing commercial refrigeration products with the lowest life cycle climate performance line on the market.