While chiller manufacturer Johnson Controls announced the compatibility of its York brand chillers with lower GWP refrigerant R513A at the AHR Expo in January, the company has warned against neglecting chiller operating efficiency and maintains that R134a remains the best overall solution.
The European F-gas regulations bans do not currently place restrictions on R134a in chillers, but with the phase-down being based on CO2 equivalents there is a drive to find lower GWP refrigerant alternatives.
With R134a having GWP of 1300, Johnson Controls, along with other chiller manufacturers, has carried out extensive tests to find an efficient, low GWP, low-toxicity, non-flammable, low cost alternative. A number of manufacturers have already announced options for new equipment or as drop-ins.
“Given that the major contributor to CO2 emissions over the lifetime of a chiller is related to the chiller operating efficiency, not the refrigerant used, lunging to a low GWP refrigerant solution that results in a reduced chiller operating efficiency may be akin to throwing the baby out with the bathwater,” said Scott Willocks, HVAC sales manager at Johnson Controls Building Efficiency UK & Ireland. “Now is a time for calm heads,” he added.
Based on its test results, Johnson Controls maintains that R134a continues to give the best balance of cost/kg, efficiency, GWP, toxicity and flammability.
“However, to alleviate any uncertainty and concerns with regards the price and availability of R134 over time, we recognise the need to “future proof” our chillers,” said Scott Willocks.
“As a result, Johnson Controls has made the decision to enhance their HFC product lines by confirming that all screw and centrifugal chillers (air-cooled and water-cooled) will be fully future compatible with R513A.”
R513A, sold by DuPont as Opteon XP10, is a binary mixture of R134a (44%) and R1234yf (56%). It has a GWP of around 630 and carries the ASHRAE safety classification of A1.
Johnson Controls’ says its choice of R513A over other alternatives, including Honeywell’s replacement blend R450A and the HFO R1234ze, was based on operating efficiency, compatibility across its range of global screw and centrifugal chillers, suitability as a “drop-in” replacement for R134a and its A1 safety classification.