Chemours2JAPAN: A Trane air-cooled chiller employing a new low-GWP refrigerant replacement for R410A is to be presented at this week’s IIR conference in Yokohama.

The Trane AquaTrine demonstration chiller is using DR-55, a Chemours development refrigerant that it will market as Opteon XL55. An A2L, “mildly flammable”, HFO-blend, DR-55 is currently being evaluated for use in unitary and residential equipment.

The AquaTrine is said to be designed for up-market apartments, luxury villas, office buildings, small restaurants, retail stores and hotels.

“We expect high performance hvac systems to be available with next generation refrigerants like DR-55 within the next 12-18 months pending regulatory approval,” said Randal Newton, vice president of enterprise engineering for Ingersoll Rand. “This demonstration project is one way that Ingersoll Rand is delivering on our environmental commitment to identify, test and introduce technologies that are safe, increase efficiency and reduce climate impact.”

Chemours is remaining tight-lipped on the make-up of the blend but the Cooling Post believes it has a GWP of around 680, making it very close to R32. Speculation suggests the blend may include both R32 and R1234yf.

Tests

The University of California (UC) recently completed testing of DR-55 as a design-compatible alternative to R410A in a Trane Precedent roof top heat pump.

“DR-55 should be considered as a possible replacement for R410A because of the relatively low global warming potential and refrigerant charge requirements,” said Curtis Harrington, associate engineer at UC Davis Western Cooling Efficiency Centre.

“Lab testing has shown excellent performance over a wide range of outdoor air conditions. Although some flammability will need to be accepted to use refrigerants with lower GWP, refrigerants like DR-55 offer greater potential for safer implementation.”

Oak Ridge National Laboratory (ORNL) recently completed demonstration testing to assess the overall performance of DR-55 as a design-compatible alternative to R410A in commercial unitary systems or roof top units (RTUs). RTUs provide more than half of the cooling to the US commercial building space.

“DR-55 is a very promising, low GWP candidate to replace R410A in commercial unitary systems,” said Bo Shen, research and development scientist at ORNL. “There is a relatively easy conversion from R410A to DR-55; therefore, it should be considered as a viable design-compatible replacement for R410A with increased performance and environmental benefits.”

Bo Shen revealed that in addition to its lower GWP compared to R410A, DR-55 systems require a 10% lower refrigerant charge, and offers significantly better efficiency and capacity, even at high ambient temperatures.

The Trane AquaTrine demonstration unit is on display at the IIR International Congress on Refrigeration until August 22.