Q&A from Energy Efficiency & Low GWP as easy as 123 webinar : 3 June 2020

Q: I have done several R32 installations, is using R454A/B/C any different?

A Climalife UK: They are all A2L refrigerants so handling precautions are the same for each refrigerant. However, for installations of different system types with different charge sizes, they may require a different risk assessment for the installation part depending on the application and use.

 

Q: In terms of prioritising importance, which would you consider more important; minimising emissions or system energy efficiency?

A Climalife UK: Both are equally important and should be prioritised, indeed minimising emissions can help maintain the energy efficiency of a system. It is well known that under charged systems use a lot more energy to run. This should apply to all refrigerants not just HFCs. Minimising and preventing leaks is the remit of service and maintenance personnel whilst system energy efficiency and life time energy costs starts with the design team and equipment selection.

 

Q: R22 system alternative refrigerant and process for replacement.

A Climalife UK: There are a number of R-22 replacements available. For Dx systems R-438A and R-453A have proven successful. Products like R-422D can no longer be used to replace R-22 in the EU as it has a GWP >2500. The producers of these refrigerants have produced conversion guidelines which should be consulted prior to carrying out the work. In some cases it may be possible to convert to R-448A or R-449A, but the TEV will probably need changing, an oil change to a POE will be required and the pressure rating of the system must be sufficient. For R-22 Flooded evaporator systems more specific information is required to be able to assess if it possible to convert.

 

Q: What low temperature (-70°C) low GWP - or lower GWP do you suggest? What about R-469A?

A Chemours: Current refrigerants (e.g. R-23 & R-508B) used for applications where the product temperature is <-50°C are exempt from the service and new equipment bans but are still included in the F-Gas phasedown schedule. Chemours does not currently have any low GWP alternatives available and have no experience with products such as R-469A. Depending on the size of equipment and any safety restrictions that may exist ethane (R-170) and ethylene (R1150) might also be considered.

A Climalife UK: R-469A is a new refrigerant that has recently been assigned an Ashrae number and is a blend of R-744, R-32 and R-125 and has a GWP of 1357. We believe it is for new equipment only and may be covered by a patent. One low temperature equipment manufacturer is offering this product.

 

Q: Advocacy on use GWP in developing countries?

A Climalife UK: The phase down of HFCs outside the EU is covered by the Kigali Amendment and has differing phase down steps and speeds. However, using lower GWP refrigerants in new equipment is to be encouraged wherever possible anywhere in the world but may depend on local availability of equipment.

A Chemours: Climate change is clearly a Global issue and as such needs to be dealt with on a Global basis and therefore it is critical that developing countries are aware of what options are available. The availability of cost effective, low total emissions refrigerants using system architectures very similar to the systems contractors are used to working with should be a very attractive options in these regions and Chemours will be making every effort to ensure very low GWP A2L solutions are included in any education programs offered to these regions.

 

Q: When might LT scroll compressors be available for A2L?

A Emerson: We are in the process of qualifying scrolls for low temperature applications and we expect to complete the range in the first half of 2021. Some models will become available earlier than this as we progress model by model through the qualification process, so please do contact us with your request if you would like to know the status of a specific compressor size.

 

Q: Has the desire for ultra-low GWP refrigerants compromised efficiency and caused an increase in indirect emissions from energy consumption?

A Chemours: As we all know the F-Gas regulation is focussed on product GWP but data published by many organisations including the European Environment Agency have shown that the vast majority (typically 80%) of emissions from a refrigeration, air conditioning or heat pump system come from the indirect emissions of energy consumption. Therefore, in the battle to lower climate changing emissions energy efficiency is a far more important factor.

As I showed on chart 14 of my presentation, in a supermarket refrigeration scenario there are numerous low GWP options available to comply with the F-Gas regulation but most of these have no or very little benefit in terms of total emissions reduction over the currently used Opteon™ XP40 (R-449A, GWP = 1397, loss rate 5%/year) and show a very significant increase in the 10-year life cycle cost. Even though refrigerants such as carbon dioxide (transcritical) and propane (in secondary water or glycol systems) have GWPs below 10, the energy efficiency of the technology is quite low and this is the main reason for the unimpressive emissions reduction and high life cycle cost.

However, the very low GWP Opteon™ XL Refrigerants (R-454A & R-454C) not only maintain but improve on the energy efficiency of R-404A or Opteon™ XP40 leading to total emissions of up to 20% lower than the baseline technology (Opteon™ XP40) and life cycle costs of at least 16% less than the other low GWP Alternatives considered.

To summarise and finally answer the question, just choosing the lowest GWP refrigerant can compromise energy efficiency and increase indirect emissions but there are very low GWP refrigerants (Opteon™ XL20 & Opteon™ XL40) that will improve energy efficiency and significantly reduce indirect and total emissions.

 

Q: Is there a total charge limit to A2l refrigerants?

related question...

Q: So regardless of room size 57kg is the maximum charge end of ?

A Chemours: There are many current standards that provide guidance on the charge size that is safe to use ranging from 1.2kg to no limits at all so without a more specific scenario it’s difficult to answer this question.

Under EN378-1:2016 in cases where refrigerant containing parts are inside an occupied space there are refrigerant charge limits which can be between 55-60kg (product dependent). This can potentially limit the size of each individual system but there is no limit on how many systems that can be in the same occupied space. Indeed, in the Asda case shown during the webinar the existing 80kW packs were replaced by 2x40kW packs in the same frame without increasing the footprint of the total system.

There are scenarios within EN378 where there are no charge size restrictions when using A2L refrigerants e.g. a cold store using a condensing unit situated outside or in a ventilated plant room where the occupancy is less than 1 person per 10m² could fall into the no charge limit category.

There are numerous different scenarios with different outcomes and this is why Chemours has developed the Opteon™ XL Charge Size Calculator tool which will be available from Opteon.com later this month.

In all these situations please remember compliance with EN378 does not remove the requirement for a thorough risk assessment.

 

Q: For users with already existing A1 equipment, how would you describe the hardest step of turning those users towards A2L and would the flammability of this material raise any sort of concern for these users?

A Chemours: First and foremost A2L refrigerants should only be used in equipment which has the manufacturers approval for using an A2L refrigerant.

A2L refrigerants have a much lower flammability than hydrocarbons but are still flammable. When using a flammable refrigerant, the same procedures must be followed in terms of risk assessment but the outcomes may be different and the level of mitigation required is often much less when using an A2L refrigerant.

It’s normal to face resistance to change but all the users who have already used A2L refrigerants have all commented it was easier than they expected so the hardest step is the initial resistance against doing something different.

A Climalife UK: A2L classified refrigerants are not for retrofitting into existing systems containing A1 refrigerants. Going forward the phase down steps of the EU F-Gas regulation and the Kigali Amendment will require new equipment to use lower GWP refrigerant than present.

Q: Slide 26?? Is 2-3 times investment cost of HFC still a relevant metric? Surely costs have changed since then.

A Emerson: Slide 26 was intended to exemplify the types of metrics that need to be compared on a case by case basis. We did not make any reference to size of system or geographical location. The point of the slide is only to illustrate that whatever systems are being compared, initial capital cost is an important driver. At least until recently, some CO2 condensing units, for example, have been significantly more expensive than HFC or expected A2L equivalents. If this is not the case in a specific comparison, it will rightly influence the choice of equipment.

 

Q: How is Emerson working with R466A?

A Emerson: We are continuously evaluating available options but until now have not made any public statements about this refrigerant.

 

Q: Does the CO2 eq on the comparison completed by WAVE include the CO2 generated during the production of the A2L refrigerants?

A Chemours: The data used for the emissions is in line with the TEWI calculations as defined in documents such as EN378-1:2016 and does not include the emissions from the manufacture of the refrigerants.

The main reason for not including these emissions is that not all the emissions from refrigerant manufacture are known. As we all know even carbon dioxide used for refrigeration is manufactured in industrial facilities and the emissions from the production of carbon dioxide is not well documented and difficult to assess. Because of this lack of data it was decided not to include these emissions which are unlikely to change the overall picture over a 10 year time scale as the indirect emissions from energy consumption are by far the biggest contributor to total emissions.

 

Q: How do you manage the discharge temp in LBP applications?

A Emerson: Low temperature scroll compressors will be equipped with an LIV (Liquid Injection Valve) that injects into the scroll in order to limit the DLT (discharge line temperature) to an acceptable value. Depending on the refrigerant used, this valve will inject more or less to cool down the gas being compressed in the scroll to reach the same DLT whatever the refrigerant.

 

Q: Why did Wave decide to choose to use 2000m2 for their cost and energy comparisons?

A Chemours: The Wave study is detailed in 2 white papers published by Chemours and looks at various sizes of supermarkets in 3 different locations to take into account high, moderate and low temperature conditions and various energy cost and energy emissions levels. To access the full information please go to:

https://pages.chemours.com/Opteon-wave-emissions.html and

https://pages.chemours.com/inconvenient-truth-technical-infographic-EN

 

Q: Is there a risk of introducing scPFCAs into the environment when these refrigerants leak?

A Chemours: Ever since the discovery of the environmental damage caused by ozone depleting chemicals there has been a great deal of focus on atmospheric chemistry and the effects of man-made emissions on the environment. This has led to many discoveries and we now have a much greater knowledge and understanding about the environmental fate of low GWP A2L refrigerants which a document published by United Nations Environmental Program (UNEP) Ozone Secretariat described as “negligible risk”. Details of research that has taken place and summaries of the results of this research can be found at:

https://www.fluorocarbons.org/position-papers/

 

Q: I am hearing that R1234yf is more toxic than R134a. Is this true and is this going to make HFO's be phased out, in time?

A Chemours: There are many ways of expressing toxicity (as you will know if you’ve ever tried to read a safety data sheet) but there are a number of sources that can be used that make this task much easier. Firstly, there are the classification systems used for the standards ASHRAE 34 and ISO 817 whereby refrigerants are classified as either A-lower toxicity e.g. R-134a or B-higher toxicity e.g. ammonia. R-1234yf is also classified as A-lower toxicity. This is a pretty broad-brush classification, but more specific information can be found in standards such as appendix E of EN378-1:2016. The tables in this section provide values for the practical limit which is based on flammability or toxicity and also the ATEL (Acute Toxicity Exposure Limit) or ODL (Oxygen Deprivation Limit) for most common refrigerants, a selection of which are shown in the following table. The higher the value the lower the toxicity.

 

Refrigerant Lower Value of ATEL or ODL (kg/m³)
R-134a 0.21
R-1234yf 0.47
Propane 0.09
Carbon Dioxide 0.072

 

Q: Are all Alco electrical components such as pressure switches and fan speed controllers now fully approved for use with A2L refrigerants?

A Emerson: Not all. The availability of components depends on the specific A2L in question. As this is an ongoing process some parts are already released and others not. Fan speed controls are not yet available from Emerson but some pressure switches are. In general, availability depends on:

Product material compatibility i.e., does the product and all its components function correctly and reliably with the specified refrigerant?

Is it safe to use in the specific application? This depends on the outcome of an appropriate risk assessment by the system manufacturer or installer. (Please keep in mind that for A2L application there is a change of PED category for some components).

In terms of point ‘1’ the Alco controls navigator shows what component is released for what refrigerant. This can be downloaded at

https://climate.emerson.com/en-gb/tools-resources/controls-navigator.

Deciding if the component is suitable for specific applications requires reference to relevant safety normatives, i.e. EN378, specific approvals such as DSEAR and components standards (e.g. EN12263 for safety pressure switches).

We are constantly updating this information so please get in touch with us directly if it is not clear what is released.

 

Q: Will the leak detector need to be specific for R455A or R454C or R32? Can we use the same R32 leak detector?

A Climalife UK: Yes it should be specific. Whilst R-445A and R-454C contain R-32 as a component, for best leak detection results and accuracy the detector should be refrigerant specific.

 

Q: Is it definite that we have to replace equipment to match these A2L refrigerants, by how much percentage?

A Climalife UK: When selecting new equipment, the F-Gas phase down process through to 2030 means that it will be impossible to continue to use the same higher GWP refrigerants as now. There is no requirement to use the Low GWP A2L classified refrigerants, but they are part of the solution to be able to remain within the quota cap over the next few years along with R-717 and R-744. As demonstrated in our webinar A2L can also give energy efficiency benefits over some of the other options. As far as the percentage goes, we have to get to 79% of the 2015 quota for 2030, this will be achieved by using low GWP refrigerants such as A2L refrigerants.

 

Q: Has the software from Chemours been approved by the creators of EN378?

A Chemours: There isn’t a single entity that “creates” EN378, it is produced by many members of committees published after a consensus has been reached and therefore it would not be practical to have the tool reviewed by all the EN378 committees. The tool has been developed with reference to the sections of EN378-1:2016 that refer to charge size guidance for A2L refrigerants and has been thoroughly error checked however this is a guidance tool and should not be used without the user having a degree of knowledge of, and access to EN378-1:2016.

 

Q: How does PED alter when using A2L refrigerant? They are different fluid groups?

A Emerson: Concerning the PED Cat, indeed changing the fluid group impacts the limits of PED categorization. Scroll compressors in the sizes we presented are PED category 1 for A1 refrigerants but category 2 for A2Ls.