Heat Pumps Today

08 October | November 2022 L O W G W P R E F R I G E R A N T S Moving to lower GWP refrigerants An essential component in a heat pump is the fluid required for the vapour compression cycle, which in recent years has been mainly R-410A, however its GWP of 2088 makes it unsustainable for new equipment. In 2019 80% of heat pumps used R-410A with R-134a being the next most common (source BSRIA). Equipment manufacturers select which refrigerant to use based on a number of parameters and are making large strides to stop using R-410A and move to lower GWP refrigerants, with R-32 (GWP 675) and R-454B (GWP 466) leading the way to replace R-410A in new equipment. Some mono-block hermetic systems with low charge sizes use R-290, whilst others use R-134a. Those who have used R-407C, mainly in Ground Source, will be able to make the move to lower GWP fluids such as R-454C or R-455A, both with a GWP of 148. All 5 of the lower GWP refrigerants mentioned above have varying degrees of flammability, so it is essential that the fledgling industry for heat pumps are properly and adequately trained to be able to install and safely maintain equipment operating on such refrigerants. Where R-134a has been used, some have made a short-term easy switch to R-513A, but longer-term R-1234yf or R-1234ze are likely to be the choice depending on equipment design. In other specialist heat pump applications, you can find R-744, R-1233zd and even Ammonia being used as the refrigerant. Legislation driving change Current F-Gas legislation will require all new single split systems with a charge below 3kg to use a fluid with a GWP below 750 from 01/01/2025. However, revision of the legislation taking place this year (2022) could mean this is extended to all Heat Pumps within 5-10 years, with smaller systems (<12kW) potentially needing to use a fluid with a GWP below 150. Some heat pump applications require the use of heat transfer fluids, and this also needs a mention as many of those used (e.g. MPG and MEG) are derived from fossil fuels. Greenway® Neo Heat Pump N is manufactured from renewable resources and also provides better performance characteristics to MPG providing significant carbon emissions reductions. The heating sector is on a journey to reduce carbon emissions and reduce fossil fuel use as it heads towards Net Zero, but most importantly, is at the start of a very rapid growth period. The sector therefore needs to embrace the technology and adapt to this change, not just for domestic use, but in other sectors as well. Time will tell if the market can travel quickly enough but what you can rely on, there is support available, from companies such as Climalife that have the products and expertise to help all involved arrive safely at the final destination. Sandra Cummings, Euan Ryan of RCIS, Patrick Harvie and Gordon Nelson at the GHF launch Info www.climalife.co.uk www.climalife.dehon.com