Trane-RTUUSA: Ingersoll Rand, manufacturers of Trane air conditioners, has endorsed the use of alternative refrigerant R452B (DR-55) as a lower GWP replacement for R410A.

The US manufacturer has also announced that it will provide royalty-free access to the patent rights it holds for the use of the new refrigerant in HVAC equipment.

The refrigerant, manufactured by Chemours as DR-55 and provisionally assigned the ASHRAE number R452B, has a GWP of 675. It is also said to exhibit lower discharge temperatures and a lower flammability than its rival R32.

Ingersoll Rand says it has been collaborating with refrigerant manufacturers, researchers, national labs and other industry partners to find a safe, high performance and efficient refrigerant alternative to R410A.

In a statement, the company says that R452B has been validated as a more efficient alternative to R410A in small chillers, residential splits and packaged unitary products.

“R452B has been tested in existing systems and requires no engineering to perform efficiently even in hot climates like the Middle East and India, and the toughest weather conditions in North America,” it said.

Efficiency gains compared to R410A were reported following tests this year by the US Department of Energy’s Oak Ridge National Laboratory using the new refrigerant on Trane rooftop units. The Trane/ORNL tests showed DR-55 providing a 5% boost in RTU efficiency compared to R410A.  Similar improvements were reported by fellow US manufacturer Lennox when testing the new refrigerant in a 17.6kW rooftop unit last year.

R452B is a blend of R32, R125 and R1234yf, DR-55 but, like R32, another refrigerant being adopted to replace R410A, it is categorised by ASHRAE as a “mildly flammable” A2L refrigerant.

“Exploration of next generation low global warming potential refrigerants with strong safety, design and sustainability performance is one way that Ingersoll Rand and Trane are delivering on our environmental commitment,” said Ingersoll Rand’s vice president of enterprise engineering, Randal Newton.

Ingersoll Rand has committed to the investment of $500m in product related research and development over a five-year period to fund the long-term reduction of greenhouse gas emissions.

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