In Part Two of this article, Peter Dinnage Technical Director at Climalife, discusses the other alternative refrigerants that can ease your move away from the high GWP refrigerant R-404A. (See Part 1 here).
Last month we highlighted the increasing need to move away from R-404A this year and looked at R-407F as an alternative to R-404A. If you missed the article it can still be found on the ACR Journal website. This month we cover lower GWP alternatives.
Lower GWP Alternatives to R404A
There are a number of alternatives approved by compressor manufacturers with a GWP significantly lower than R-404A and whilst each have slightly different properties, it is their GWP where there is most difference. Both R-448A and R-449A have GWPs (AR4) just below 1400. Both contain R-125, R-134a, R-32 and R-1234yf, but R-448A also contains R-1234ze and it’s the presence of the HFOs which take the GWP lower than that of R-407A (2107) and R-407F (1825). Both these lower GWP alternatives can be used in supermarkets, cold stores and direct expansion food processing applications that have previously used R404A.
Pressure temperature tables are available in various forms and feature on many of the popular free slide rule apps that are now available for smartphones.
R-449A (Opteon™ XP40) is already proving a suitable alternative to R-404A with use growing across Europe in a wide range of applications. In the UK it has already been used in new convenience store applications and has been trialled in a number of larger supermarkets for retrofit and roll out in 2016 in further stores.
On the industrial side it has been used successfully for retrofit and has proven to be an easy conversion to carry out from R-404A, with no need to change from the POE oil used with R-404A. Where electronic expansion valves are in use, they can be adapted to R-449A whilst a small adjustment of thermostatic valves and the superheat settings are usually required for optimum operating conditions.
To meet the phasedown requirements of F-Gas in 2018, retrofitting of existing R-404A equipment to lower GWP refrigerants is going to be vital to ensure the reduced quota meets the demands of the market. The lower GWP refrigerants such as R-449A (Opteon™ XP40) and R-448A will have a major part to play.
It is always worth remembering that if you are retrofitting to follow the conversion guidelines from the producer / supplier as this will help ensure the check list is followed and potential pitfalls are avoided.
A2L Refrigerants as R404A replacements
However, A2L rated refrigerants will not be a retrofit option due to their mild flammability and even for new equipment there will be charge size restrictions based on the size of the room which will limit their use to small equipment.
Some of these A2L refrigerants with low GWP will be a good option for new systems with a small charge, however the selection and approval process will be led by the equipment manufacturers and that may take time and assumes EN378 will formally incorporate the recommendations now on the table.
The need to replace R404A
Do also speak to refrigerant specialists, such as Climalife, to review all the options available to you and ensure it is the right choice for your particular system.