Chilling Out with Refrigerants

Up until the mid-1980’s, the type of refrigerant to be used in a building’s cooling system was, at best, an afterthought of the consulting engineer and building owner. But increasing awareness of the harm that once-common chlorofluorocarbon (CFC) refrigerants were causing to the ozone layer forced the industry to find alternatives.

Part of the industry’s response was to use hydrochlorofluorocarbon (HCFC) refrigerants, such as R-123 and R-22, which have a much lower impact on the ozone layer compared to CFCs. However, the Montreal Protocol, signed by over 190 countries in 1987, called for the eventual phase-out of HCFCs due to the fact that their ozone depletion potential (ODP), although small, is not zero. In 1992, the Environmental Protection Agency established a phase-out schedule severely limiting the production of R-22 by 2010. The use of R-22 already out in the open market will not be restricted, but its installation in equipment manufactured after 2010 will be prohibited. Similarly, R-123 has a manufacturing phase-out date of 2020.

What does all of this mean for a building owner presently faced with the purchase of new, refrigerant-containing cooling equipment? It means that there are new refrigerant options that should be considered when purchasing equipment. Alternative refrigerants containing hydrofluorocarbons (HFCs) such as R-407C, R-410A, and R-134a may be better options over HCFCs, as these refrigerants will be widely available in the long-term and are not scheduled for phase-out, due to their zero ODP. There is currently a small cost premium for equipment using HFCs, resulting from prior equipment designs being upgraded to use this refrigerant type.

“In 1992, the Environmental Protection Agency established a phase-out schedule severely limiting the production of R-22 by 2010.”

Although there are some small energy efficiency and global warming potential differences between the alternative HFCs, the ability to choose one over the other in a given piece of cooling equipment may be limited by the equipment manufacturers. For example, of the available HFC refrigerants, only R-407C and R-134a are available in small water chillers. At this time, there is some uncertainty as to whether R-407C or R-410A will come to govern the unitary HVAC market (rooftop units, split systems, heat pumps, etc.), but it is clear that both will see increased use as the R-22 phase-out date approaches. R-134a appears set for domination of the large water chiller market (above 200 tons) for the foreseeable future, as all but one of the four major chiller manufacturers have abandoned R-123 in favor of R-134a.

Building owners need not be overly concerned about R-22 availability problems. There is, and will be for some time, a large stockpile of recycled R-22 available for service and system re-charging of equipment that uses this refrigerant. R-407C can even be retro-fitted into many pieces of equipment that were originally designed for R-22, with only minor cooling capacity reductions. By being aware of the above information and keeping an eye on industry trends, building owners can stay clear of the pitfalls of a changing refrigerant industry.

– Tom Hovan, PE