The Air-Conditioning, Heating, and Refrigeration Technology Institute (AHRTI) released the first research report as part of its ongoing testing of flammable refrigerants. Many of these refrigerants were identified as possible replacements to high global warming-potential (GWP) hydrofluorocarbons that will be phased down under the Montreal Protocol.

AHRTI is the research arm of the Air-Conditioning, Heating, and Refrigeration Institute (AHRI). The research and testing program is part of a $5.2 million commitment on the part of AHRI, ASHRAE, the U.S. Department of Energy, and the California Air Resources Board to further test in real-world settings low-GWP, but mildly flammable or flammable, refrigerants.

"The ongoing global effort to phase down the use of high-GWP potential refrigerants requires this vital research, which will help us update relevant codes and standards so that appropriate, climate-friendly alternatives can be safely used in air conditioning and refrigeration equipment," said Karim Amrane, AHRI's regulatory and research senior vice president.

The report, Benchmarking Risk by Whole Room Scale Leaks and Ignitions Testing of A2L Refrigerants, was developed following testing at UL, which began in June 2016. The objective was to conduct refrigerant leak and ignition testing under real-world conditions to develop data and insight into the risk associated with the use of A2L refrigerants, which are mildly-flammable, but have a low-GWP. Room scale tests were performed for commercial and residential scenarios, including a packaged terminal air conditioner in a motel room, a rooftop unit in a commercial kitchen, a walk-in cooler, a reach-in refrigerator in a convenience store, a split HVAC unit in a utility closet and with servicing error, and a split HVAC unit with hermetic electrical pass-through terminal failure. A copy of the report is available here.

"The testing was designed to create relatively low-probability events to evaluate if the ignition spread or had the potential to spread if ignition took place," said Amrane. "This means that more refrigerant was leaked into the space during these tests than what is proposed by the standard. In other words, a worst case scenario."

Further testing is planned as part of this effort and results will be released when they are available.