The Obama administration signed onto a deal over the weekend with nearly 200 countries to combat global warming by phasing out the refrigeration chemicals used in air-conditioners, even as industry scrambles to find replacement chemicals needed to keep homes cool and food fresh.

Environmental Protection Agency Administrator Gina McCarthy, who was key in securing the deal, said the chemicals represent potent greenhouse gas emissions, called hydrofluorocarbons, or HFCs, that are causing harmful man-made climate change, and are thousands of times more potent than carbon dioxide.

"In a nutshell, these HFCs cool our homes and chill our food, but they are turning up the temperature of our planet," McCarthy said. "And over the next several years, HFC use is expected to not only grow — but multiply," and "that's why, this week in Rwanda, world leaders took a giant leap forward by agreeing to a global phase-down of these harmful gases."

The deal was agreed to in Kigali, Rwanda, and lauded by the administration as a key part in meeting the goals of the president's climate change agenda before his term is up this year. The EPA will also have to put in place regulations to specifically phase out the chemicals in the United States.

Secretary of State John Kerry said the deal, which would be legally binding, would put the planet on track to stop the Earth's temperature from rising a half of a degree Celsius over the next two decades. The deal will not require ratification by Congress because it is an amendment to the three-decades old Montreal Protocol that was established to stop damage to the ozone layer.

The deal was described by clean energy proponents as just as significant as last year's Paris climate change agreement, another big priority for the administration, despite the lack of fanfare.

"Today's meeting in Kigali may not have drawn the same fanfare as last year's Paris summit, but the result — a legally binding agreement by 170 nations to significantly curtail the use of hydrofluorocarbons, a serious greenhouse gas found in air-conditioners — will have a tremendous effect on the world's ability to prevent the worst climate change impacts," said Lord Mark Malloch-Brown, chairman of the Business & Sustainable Development Commission, an environmental sustainability group.

"While governments have taken the lead through this agreement it will be up to the private sector to find innovative, affordable and climate-friendly ways to cool billions of people affected by a warming planet," Lord Malloch-Brown added.

Industry officials point out that despite supporting the agreement in Rwanda, the deal to phase out the chemicals is just the first step in implementing it. The ambitious agreement calls for industry to step up research and development efforts to find and produce enough of the right chemicals to replace the climate-harming HFCs.

"The agreement is just the first step in a multi-step process," said Stephen Yurek, the head of the Air-Conditioning, Heating and Refrigeration Institute, representing air-conditioning and refrigeration manufacturers.

"Our industry is hard at work doing the research on the HFC alternatives that will be used in the world's air-conditioners, heat pumps and refrigeration equipment, and getting that right is certainly as important as reaching agreement," Yurek added. "Also very important are the education and training initiatives that will have to occur to ensure safe, efficient installation of the equipment that will contain these new refrigerants."

Yurek, however, points out that some of the current HFC replacement chemicals for a home and commercial air-conditioning unit are potentially more flammable and must undergo further safety tests before phase-in can begin.

"After two phases of research, the most promising alternatives are currently classified as mildly flammable or flammable, so additional field research is being undertaken to determine their suitability in different applications," he explained.

That research is currently being sponsored by Yurek's group, the Department of Energy, the state of California and the American Society of Heating, Refrigerating and Air-Conditioning Engineers.