ALTERNATIVE REFRIGERANTS
and found it to present no more risk than the use of R134a. Manufacturers are well versed in the use of this refrigerant on production lines, although it does require those servicing cars to be aware of the differences.
Some large chillers are now using R1234ze as an alternative to R134a. R1234ze is an HFO and is classified as A2L, but it is actually non flammable at temperatures below 30°C. Because of this property, R1234ze is also being used in some aerosol
applications, again as a replacement for R134a.
R1234yf is a closer match to R134a which makes it suitable as a direct replacement in chillers where the system is designed to use a mildly flammable refrigerant.
Refrigerant manufacturers are also trialling A2L HFO blends as replacements for R404A, R410A, etc type applications. A number of these were commercially launched at Chillventa in October 2016.
Use of A2L refrigerants
It is vital to understand that A2L refrigerants must only be used in new systems designed specifically for their use. They should not be used to replace non-flammable refrigerants in retrofit situations.
Due to the mild flammability, 2L refrigerants are intended for use in equipment specifically designed for these products and should always be used in accordance with the relevant national or international standards.
Please consult the appropriate equipment manufacturer regarding which refrigerants can be used in the equipment
Q. Who can work on F-Gas systems? All technicians that carry out work on stationary systems must hold an F-Gas handling certificate. This requirement applies both to in-house staff and to personnel employed by external contractors.
Existing certificates issued in accordance with the 2006 EU F-Gas Regulation remain valid, in
30 December 2016
accordance with the conditions under which they were originally issued, and therefore installers existing training covers new A2L refrigerants. However, it should be noted that additional training has to be given on alternatives when the F-Gas certificate is updated.
Q. What are typical filling charges for A2L Refrigerants?
Filling charges are usually covered by the respective codes and standards for refrigeration equipment – the general safety and use standard ISO 5149 ‘Refrigeration systems and heat pumps’. There are also more specific standards covering selected appliances, such as the IEC 60335-2 series. ■ IEC 60335-2-24 for ‘refrigerating appliances, ice-cream appliance sand ice makers’
■ IEC 60335-2-40 for ‘electrical heat pumps, air- conditioners and dehumidifiers’
■ IEC 60335-2-89 for ‘commercial refrigerating appliances with an incorporated or remote refrigerant unit or compressor’.
Check your local regulations and the correct standards such as those listed above to verify the allowable filling charge, new equipment design and safe handling requirements for the intended application.
The graph above shows that you can typically use more than 10 times the charge of a 2L refrigerant compared to an A3 highly flammable refrigerant – consult EN378 for the limits for specific equipment, location and application.
Service equipment
Many of the service items used for current A1 refrigerants can be used for servicing A2L refrigerants.
However, some service equipment, due to the electrical components and motors, should be specifically designed for use with mildly flammable A2L refrigerants – for example, R1234yf, R32, etc – which also needs to be compliant with local regulation. All service should be conducted in a safe manner and with respect to the guidelines given by the relevant codes and standards in your country/region.
New A2L service items should be available as there is an increasing number of service equipment companies providing these tools.
In conclusion
To meet the requirements of the F-Gas regulation phase down process, it will be necessary to make use of refrigerants with much lower GWPs. This means that the RACHP industry will need to begin to use the new A2L refrigerants as part of this process, as the effects of the phase down begin to bite.
There is no reason why these new refrigerants cannot be used safely in a wide range of applications, providing guidance and regulations are observed, and good practice is used.
FETA wishes to acknowledge the contribution of a number of its members in the preparation of this article.
www.acr-news.com
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