A row of air conditioners span a rooftop on a sunny day

Summary of background work, including research and testing, contributing to the revised requirements for A3 refrigerants within IEC 60335-2-40: 2022

This report provides an overview of the background work including safety research, and testing, to evaluate the safe design and installation of air conditioners and heat pumps using A2/A3 refrigerants during the course of 7 years of developing the International Electrotechnical Commission (IEC) 60335-2-40 standard Edition 7, published in 2022, which enables widespread safe use of hydrocarbon refrigerants in air conditioners and heat pumps. A3 refrigerants include R-290 (propane) and other climate-friendly, ultra-low global warming potential hydrocarbon refrigerants. This report was commissioned by EIA-US and authored by Daniel Colbourne, an independent technical expert and member of the IEC Sub-Committee 61D working groups on A2/A3 refrigerants.

EIA urges stakeholders in the U.S. to utilize this and other available resources developed during the IEC’s process of evaluating the safe use and installation of equipment using R-290 and other hydrocarbon refrigerants to jumpstart the process of harmonizing U.S. safety standards and building codes (including UL 603352-40, and ASHRAE-15) with the international IEC standard, in order to make ultra-low global warming potential (GWP) ACs and heat pumps available in the United States and North America.