Characteristics of A2L fluids

Source: Answers to the questions asked during the A2L webinar on May 7 organised by Climalife in partnership with Tecumseh and Honeywell




Pierre-Emmanuel Danet, Technical Support Manager at Climalife
Alain Lelièvre-Damit, Purchase & Quota Manager at Climalife
Regis Leportier, Technical Programs Director at Tecumseh Europe
Jean De Bernardi, Technical Team Lead at Honeywell Refrigerants




What is the difference to A3 in terms of safety devices required?
A2L is a different category of flammability compared to A3.
The IEC60335 series of standards must be applied for the system. The standards cover: electrical, mechanical, thermal, fire and radiation hazards of the appliances when operating as in normal use, taking into account the manufacturer's instructions.
They also cover abnormal situations which may be expected in practice and take into account electromagnetic phenomena which may affect the safe operation of the equipment.
If your appliance does not comply with these safety standards, you must follow the EN378 for any safety measures to be applied linked to refrigerant charge limits.




What effect do they have on discharge temperatures in comparison with HFCs?


HFOs are generally similar to, or cooler at the compressor’s discharge than the other refrigerant fluids used.  
However, as these refrigerants are A2L, they should not be used in the conversion of existing installations: they are fluids that must be used in new installations, and the discharge temperatures are therefore taken into account by compressor OEMs and assemblers.




Why is R1234ze in the A2L? MSDS says clearly non-flammable!
It is clearly noted as non flammable product, this is because R-1234ze is not flammable under 30°C. Consequently it is noted as non-flammable in the MSDS for transport and storage.




Can A2L refrigerants also be used for refrigeration system like chillers and freezers?
At Honeywell we have solutions for each application: chillers are already using either R-1234ze or R-515B.
For Refrigeration we can either use pure HFO in cascade or use our R-455A blend, which can provide refrigeration even below -50°C.

When we will have one A2L refrigerant equivalent with R404A ?
We have it! It’s R-455A.

Can I use A2Ls for high temperature heat pumps? Up to 80°C?
Yes, HFOs are refrigerant fluids that make it possible to get very high condensing temperatures thanks to their extremely high critical temperatures.
For example, R-1234ze can even be used to boil water because its critical temperature is around 110°C. Most of the commercially available heat pumps which use R-1234ze today allow water to be heated at 85°C without any problem.
R-1233zd could even go higher and reach 160°C without any problem.




Why would I use A2L refrigerants when A3 are more efficient? The measures to be taken regarding flammability are the same.
It is true that some A3 fluids such as propane are very efficient. It is inaccurate to say that they are more efficient than HFOs: this will essentially depend on the compression technologies used and the operating conditions in the operating envelope.
That being said, the main differentiation will be in terms of risk in use: this is why the possible refrigerant charges for HFOs per circuit are generally around 10 to 12 times higher than those possible with hydrocarbons according to EN378 or ISO5149.

What are the forecasts for price (cost) reduction for R-1234yf and other refrigerants containing R-1234yf?
The price of refrigerants is highly dependent on the supply chain, so there is no unique answer to the price evolution. What is certain is that the history of refrigerants has shown that the effects of mass production has always led to a gradual reduction in costs over the years.

Is to possible to use alternative refrigerant in US market? Are the refrigerants L40X homologated by EPA?
The problem is not so much EPA or Snap approvals in the U.S. (which are okay for HFOs depending on the major applications), but rather building codes that are evolving to accommodate the use of A2L fluids.
I therefore suggest to check these building codes and their evolution as well as possibly the rules specific to each state.

Regarding the environment: ODP and GWP are good for HFO, but what about the production of TFA? I am only aware of studies that say that the use in MAC will not cause a problem. What if HFO becomes the major refrigerant in all retail and comfort cooling installations? Will this be safe for our water end the environment?
There is so much misinformation on this subject that I urge you to hold on to the facts.
The most independent scientific source to date is the United Nations report in charge of the Montreal Protocol (UNEP), which definitively settled the issue in favour of the insignificant impact of HFOs on existing stock of TFA.
It is important to know and understand that TFAs are natural occurring acids produced by underwater volcanic activity and there are now more than 200 million tons of TFA in the oceans.
Check the UNEP report




What is the difference between L40X versus N40? How do we select for best refrigeration performance?
The difference between the Solstice L40X (R-455A) and Solstice N40 (R-448A) is the classification. R-455A is an A2L refrigerant and R-448A is an A1. Both refrigerants have better performance than R-404A. Your choice will therefore depend on the installation (existing or new). In a new installation, it is still recommended to choose the solution with the lowest GWP. In an existing installation, you have to choose R-448A to stay within same classification.




How did you evaluate the risk of generation of hydrogen fluoride in case of an ignition...nevertheless it is still a flammable gas!
After applying the conclusions of the risk analysis, since the refrigerant fluids we chose were at the lowest end of the risk scale, the possibility of ignition was virtually non-existent.
The two situations that remain possible are ignition related to a brazing torch or an existing fire. In both cases most refrigerants, including all HFCs used today, will burn and generate HF. So there is nothing new that does not already apply related to this topic with the application of the A2Ls we offer.




Watch the webinar replay: Be part of eco responsible refrigeration !