Energy efficient heat pumps with Opteon™ XL low GWP HFO refrigerants for buildings’ renovation

Renovated buildings require an extended operating temperature range from their Heat Pumps, especially when compared to new buildings. This is due to the legacy system of hydronic radiators, which require higher water flow temperatures to achieve heating capacity needs than in-floor heating, for example.Due to the often absent or less-efficient thermal insulation of older structures, the required heating capacity may be even higher than estimated herein.

Heat Pumps using existing refrigerant technologies – namely R-410A – cannot meet these requirements across an entire year, as at very low ambient temperatures, additional electrical heaters in the buffer tank or separate fuel or gas boilers are needed to provide the necessary heating capacity. Both of these solutions provide much lower efficiency and generate much higher total system emissions.

With the low-GWP (148) refrigerant Opteon™ XL 20 (R-454C), system efficiency can be improved compared to R-410A over the entire operating range, and in all temperature conditions. In addition, a flow temperature up to 75 °C can be easily achieved without additional technical measures, like vapor or liquid injection. In this way, system and maintenance costs can also be reduced. It has also been demonstrated that the direct emissions from Opteon™ XL 20 (R-454C) represent less than 1% of the total emissions over the complete lifetime of a Heat Pump.

This leads to the conclusion that system efficiency is the main parameter influencing system emissions by reducing operational power consumption.