BNCR35: Overview of New and Alternative

Version 1.2

This Briefing Note and referenced information is a public consultation document and will be used to inform Government decisions. The information and analysis form part of the Evidence Base created by Defra’s Market Transformation Programme.

1 Summary

This Briefing note is an overview of existing and alternative refrigerants and includes summary of main legislations and regulations. It also illustrates main characteristics of these refrigerants and their application and usage. All existing and new/alternative refrigerants and their corresponding designation and composition are listed in Appendix 1.

2 Introduction

With the discovery of the link between (CFCs) and hydrochlorofluorocarbons (HCFCs) and the depletion of the ozone layer, the United Nations Environment Programme (UNEP) formulated the Montreal Protocol in 1987 to phase-out the use and production of these substances. In response to the Montreal Protocol, alternative refrigerants were sought, and this search produced a number of potential substances for applications where only CFCs and HCFCs were previously used: hydrofluorocarbons (HFCs), (HCs), and (CO 2). Simultaneously, attention focussed on the issue of climate change. Subsequently, the Kyoto Protocol was developed under the UN in 1997, which prescribes the limitation and reduction of emissions of a group of anthropogenic “greenhouse gases” (GHGs): CO 2, (N 2O), (CH 4), HFCs, perfluorocarbons (PFCs) and sulphur hexafluoride (SF 6). Numerous governments, including the European Union, have since published legislation to help meet the Kyoto targets for emissions reduction. In order to quantify the contribution of these gases to climate change, the discussions on climate change in 1990 adopted the use of (GWP) of the gas (IPCC, 1990). GWP is a measure of the insulating properties that a gas has on the heat radiating away from the surface of the earth, and is relative to the effect of one kilogram of CO 2.

Ultimately, these political actions have resulted in a drive by the refrigeration and air- conditioning (RAC) industry to reduce the environmental impact of systems, manifest

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as development of new refrigerants and cooling technologies. This document addresses the following related issues:

• options • Characteristics of alternative refrigerants • Environmental impact • Efficiency and applications of alternative refrigerants • Refrigerant leakage • Recent developments and technical barriers

The number of available refrigerants is vast. Appendix 1 lists those with an “R- number”, as defined in EN 378: 2000 (and ISO 817 and ASHRAE standard 34). Out of about 110 designated refrigerants (excluding CFCs) only about ten are being used extensively in industry. In addition there are several hundred commercially available fluids that have not been allocated an R- number to date. In order to maintain focus, only refrigerants with an R- number and those significant to future use will be discussed henceforth.

3 Summary of refrigerant options

3.1 Legislative requirements The possible choice of refrigerant for new systems varies globally as a result of national and regional legislation, but is largely dictated by the requirements of the Montreal Protocol (and subsequent amendments). In general, CFCs have already been prohibited in developed countries (from 2001 in the EU), and phase-out of HCFCs is occurring at present. However, a large number of countries have produced national legislation that accelerates these phase-out schedules; within the EU as from 2004 HCFCs were prohibited in all new systems and their use for servicing (including recycled HCFCs) will also cease in 2015. Similarly, national and regional legislation originating from the Kyoto Protocol will also impact on refrigerant choice. For example, in Denmark, Norway, Austria and Switzerland the use of high-GWP refrigerants is being prohibited in a number of different applications and/or a GWP- tax is applied to the purchase of such refrigerants. To date the UK Government has not produced any specific legislation, although in their Climate Change Programme they provide a general policy on HFCs. This states that “HFCs should only be used where other safe, technically feasible, cost effective and more environmentally acceptable alternatives do not exist”, and that “HFCs are not sustainable in the long term – the Government believes that continued technological developments will mean that HFCs may eventually be able to be replaced in the applications where they are used” (DEFRA, 2006).

New European legislation (which was agreed in January 2006) has imposed some controls on the use of HFCs (the “F-gas” regulation and directive). The main provisions in the regulation (Regulation EC No 842/2006 on certain fluorinated greenhouse gases) cover:

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• containment through responsible handling during use; • recycling and end-of-life recovery; • training and certification for personnel involved in the containment and recovery of f-gases; • reporting on quantities produced, supplied, used and emitted; • labelling of products and equipment; • certain application specific controls on use; • certain placing on the market prohibitions.

The directive (Directive 2006/40/EC relating to emissions from air-conditioning systems in motor vehicles) will place restrictions on the types of Mobile Air Conditioning (MAC) systems fitted to vehicles before vehicles are approved for sale, and specifically:

• a two-step phase out of MACs that use f-gases with a GWP greater than 150: 1 January 2011 for new types of vehicle, and 1 January 2007 the sunset date for all new vehicles; • maximum annual leakage limits within the interim period before the phase out; • controls on refilling and retrofitting for these systems.

Both the Regulation and Directive will enter into force in 2006 with the main body of the provisions in the set to apply from one or two years after that date.

3.2 Characteristics of common refrigerant types

This section provides a summary of the various types of refrigerants that are broadly applicable to domestic and commercial RAC equipment. Important characteristics such as chemistry and compatibility, pressure-temperature and thermophysical properties, safety (toxicity and flammability) and direct environmental impact are mentioned. A comprehensive list of refrigerants is provided in Appendix 1, including basic information on composition, normal (NBP), safety and environmental data.

Chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs)

CFCs and HCFCs were the standard refrigerants for most new RAC applications, and R12 and more so R22 are the reference fluids for the development of new refrigerants. In general, CFCs and HCFCs have broad compatibility with many materials, adequate solubility with most types of refrigeration oils (although most often used with mineral oils) and are relatively tolerant of contaminants in the system. Amongst the various fluids in these groups, a wide range of pressure/temperature characteristics are available and their favourable thermophysical properties result in good cycle/system efficiency.

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Hydrofluorocarbons (HFCs)

HFCs such as R134a, R404A 1 and R407C have dominated the replacement of CFCs and HCFCs, mainly because they broadly possess similar chemical, thermodynamic and flammability/toxicity characteristics as well as having been extensively marketed by manufactures. However HFCs are more difficult to apply because of poor compatibility with construction materials and in particular mineral oils, which has meant that certain synthetic lubricants, typically polyolesters (POEs) and polyalkylglycols (PAGs) have to be used instead. Moreover, they are less tolerant to contaminants within the system. Most HFCs are used in binary or tertiary mixtures, partially to suit certain desired operating characteristics such as replicating R22. HFCs tend to have low toxicity and are largely non-flammable, although a couple of fluids, such as R32 and R152a that are used in several blends are flammable. In terms of environmental impacts, although HFCs have a negligible ODP they do retain the high GWP characteristic of most fluorinated refrigerants, hence the introduction of afore mentioned legislation. Of lesser importance are some other environmental impacts associated with HFC production and emissions, including the release of ozone depleting substances during their manufacture (Banks and Sharratt, 1996) and the production of trifluoroacetic acid as a decomposition product which is highly persistent and bio-accumulative may be harmful to aquatic life (IPCC/TEAP, 2005).

Hydrocarbons (HCs)

HC refrigerants include a broad range of substances (e.g., R600a and R290) that cover the range of pressure-temperature characteristics of the conventional CFC and HCFC fluids, and they have been used since the evolution of mechanical refrigeration. Also their good material compatibility and solubility with lubricants is comparable to that of the CFCs. Certain thermophysical properties do differ from the fluorinated fluids, particularly in terms of lower density and higher latent heat. The most significant property associated with HCs is that they are all flammable (but low toxicity), which means that certain safety measures not normally applied to RAC equipment must be adhered to. Apart from this issue, their ease of application, good efficiency and negligible GWP makes then attractive refrigerants.

Carbon dioxide (CO 2, R744)

CO 2 is another fluid that has been used as a refrigerant for well over a century. It is has good chemical compatibility with common materials and relatively good solubility with a number of oils (Kim et al, 2004). Whilst non-flammable, CO 2 is toxic at moderate concentrations, particularly above 5% by volume in air. Also, CO 2 has no ozone depletion potential, negligible GWP and has no other serious environmental problems associated with it.

The notable difference between CO 2 and other common refrigerants is its pressure- temperature characteristics, and in particular a low critical temperature of

1 R507A is covered in any reference to R404A since they are essentially the same but a few percent variation in composition.

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approximately 31°C. This means that it either operates with a limited (low) condensing temperature, or it must be used in a “transcritical” or “supercritical” cycle that differs from conventional compression cycles. In a transcritical cycle the refrigerant in a supercritical state is discharged from the compressor and enters a “gas-cooler” (rather than a condenser) where its temperature is reduced before being expanded into a liquid and vapour state, usually in the evaporator. CO 2 also operates at significantly higher pressures and has a very high latent heat when compared to most conventional refrigerants. The basic transcritical cycle is potentially less efficient than a conventional compression cycle because it suffers from larger thermodynamic losses. Higher heat rejection temperatures result in greater throttling losses and so the theoretical cycle work increases and refrigerating capacity is reduced. Although the excellent thermophysical properties of CO 2 mean that performance within the heat exchangers and compressor are generally better than with conventional refrigerants, it is not always sufficient to overcome the additional losses associated with transcritical operation. This is manifest in the significant research efforts on means to improve cycle efficiency, such as development of expanders (instead of expansion valves), ejectors and interchangers so that losses can be recovered.

Ammonia (NH 3, R717)

Ammonia has been used continuously for many years and is well understood. Unlike HCFC, HFC and HC refrigerants, ammonia (in the presence of small amounts of contaminants) is incompatible with a number of materials otherwise commonly used in refrigeration systems, and it is immiscible with most lubricants. The pressure- temperature characteristics of ammonia are similar to R22, whilst the latent is significantly greater than most fluorinated fluids. Ammonia also possesses favourable thermophysical properties, resulting in good efficiency. There are safety implications with ammonia both in terms of toxicity (although perceived to be much more severe due to its pungent smell) and moderate flammability. On the other hand it has negligible environmental impacts, i.e., no ODP and no GWP.

Mixtures and other fluids

There are a number of available mixtures that may contain various components including HFCs, HCFCs, HCs and PFCs. These mixtures are generally produced for the purpose of drop-in or retrofit refrigerants. The inclusion of HCFCs or HCs is to provide some solubility with the mineral oils that are used in existing CFC or HCFC systems. In other cases, such mixtures are developed to match particular characteristics of a specific refrigerant that it is intended to replace, or to achieve an improvement in cycle efficiency.

Given the possible number of combinations of the various fluids mentioned above, the extent of different characteristics is vast. Mixtures fall into two categories: azeotropes (refrigerants with R5xx designation) and zeotropes (with R4xx designation). Azeotropes behave more or less identically to pure fluids, whereas

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zeotropes exhibit certain unique characteristics particularly during change of phase. In flooded systems, zeotropes will demonstrate a composition change due to the different vapour pressures of the refrigerant components and a larger difference in vapour pressures normally causes a greater extent of composition change. As the system operates, the component(s) with a lower boiling point accumulate within the high pressure-side, and higher boiling point component(s) shift to the low pressure- side of the cycle. Consequently compression ratio increases, refrigerating capacity reduces leading to a degradation in system efficiency. In flooded systems, the degree of composition change causes sufficient disruption to the performance of the cycle that they are not recommended for use.

In direct expansion (DX) systems composition change occurs to a much smaller extent and instead the range of component vapour pressures is exhibited as a variation in saturation temperature across the phase change, which is known as “glide”. Temperature glide for common refrigerants ranges from 0.5 K to about 10 K, and for a given mixture it gets smaller as the saturation pressure/temperature approaches the critical point. In DX systems, glide can be suitably accommodated provided that heat exchanger design is addressed. Another impact of the use of a mixture is degradation of two-phase heat transfer in the evaporator and condenser, occurring because of the differential rate of phase change between the refrigerant components.

New refrigerant products

The announcement of the European Commission that refrigerants with a GWP > 150 are to be prohibited from MAC systems has generated the development of a number of substances not previously considered. The current standard refrigerant for automotive air conditioning is R134a and its high GWP means that it is subject to this restriction. Automotive applications account for approximately half of the global HFC sales (UNEP, 2002) and therefore a significant proportion of the HFC refrigerant business is threatened. Consequently, a number of new synthetic refrigerants are under development as replacements for R134a, and possible fluids include hydrofluoroethers (HFEs, low GWP and low pressure), fluoroiodocarbons (FICs, low GWP and generally toxic) and a group of unsaturated HFCs or fluoroalkenes (HFOs, low GWP) although little else is known about their other properties. There are specific fluids and mixtures (including with HFCs) that are currently under consideration and these include:

• R152a (HFC) and R13I1 (FIC) • R32 (HFC) and R13I1 (FIC) • R1234yf (HFO) and R13I1 (FIC) • R1234ze (HFO) and R13I1 (FIC) • R1234yf (HFO) and R1225yez (HFO) • R1243zf (HFO) and R13I1 (FIC)

Manufacturer’s claims vary and to date detailed technical information is scarce, but in general they are indicated to have GWP < 150 but potential volatile organic

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compounds (VOCs), non-flammable, pressure-temperature characteristics and performance close to existing refrigerants, and can use conventional lubricants. However, given that manufacturers have acknowledged that material compatibility and toxicity testing is yet to be completed, it may be several years until these or similar fluids are commercially available.

3.3 Refrigerants in common use

There are a variety of factors that affect the choice of refrigerant for new equipment. These include thermodynamic, chemical, safety and environmental properties, as well as practical and market implications such as cost, global availability of the fluids and system components, and technical familiarity of engineers and technicians. In particular equipment producers tend to consider the offset between GWP and flammability/toxicity according to the intended product market. Another important factor for manufacturers adopting new refrigerants are modifications to production processes, system design and component construction, all of which can impose significant costs on new RAC equipment. These factors are more relevant to larger, global manufacturers where they are seen to employ fewer refrigerant types whereas smaller producers exhibit greater diversification in their choice.

Within Europe, the most common refrigerant options for new systems are presently HFCs, HCs, ammonia and carbon dioxide. Table 1 lists the specific fluids based on an international assessment report produced under the Montreal Protocol (UNEP, 2002), and the previously used CFCs and HCFCs are also included for comparison.

It is important to note that older equipment that was produced with HCFCs and particularly CFCs poses problems when subject to repairs. If it is not possible to use the existing ODS refrigerant because of restrictions, several options are considered:

• replacement of old systems with new ones designed with a non-ODS refrigerant, • “retrofit” where the old refrigerant is replaced with a non-ODS one but accompanies with oil and material change due to compatibility issues, • “drop-in” where the old refrigerant is simply swapped with a non-ODS refrigerant.

The first option is the most costly, but offers other benefits such as more efficient systems and reduced maintenance. The retrofit option may include changing to an HFC, which requires some time and expenditure to remove all the mineral oil and certain materials from the system and replace them with those suitable for use with HFCs.

Using a drop-in refrigerant (typically involving mixtures of HFCs with PFCs and HCs) is the cheapest and most accessible option. It is also possible to drop-in using pure HCs, but this involves modifications to equipment so that the safety features required by standards such as EN 378 are addressed.

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Table 1: Common refrigerants used in existing and new equipment

Sector/ equipment ODS refrigerants GWP refrigerant Natural refrigerants Domestic refrigeration R12 R134a R600a Retail refrigeration · Integral units R12, R502 R134a, R404A R600a, R290, R744 · Split/condensing units R502, R22 R404A R290, R744 Centralised · R502, R22 R404A R1270, R744, R717 supermarket Stationary air conditioning · Unitary/split R22 R407C, R410A R290, R744 · Chillers R22, R123 R134a, R407C R290, R1270, R717 · Heat pumps R22 R407C, R410A R290, R744

Domestic refrigeration

Following the phase-out of R12, R134a was adopted within the domestic refrigeration sector but since then R600a has become the established choice throughout Europe and much of Asia. This is primarily because it enables lower noise levels to be achieved, which is an important factor for residential environments. In addition, R600a offers a slight efficiency improvement over the competing fluids suitable for this application and despite the minute likelihood of leakage its negligible GWP is considered an advantage.

Commercial refrigeration

Commercial refrigeration includes stand-alone units such as vending machines, ice cream freezers and bottle coolers, to remote systems such as those used for coldstores and display cabinets in retail outlets. Integral units generally use R134a (mainly for medium temperature applications) and R404A (mainly for low temperatures). More recently, the use of R290 and CO 2 and to a smaller extent R600a have been adopted. Remote systems that employ condensing units or a central multi-compressor pack have become limited to R404A because of established industry practice. However, a number of alternative concepts such as indirect and cascade systems are being installed with increasing frequency, and these allow for the use of HCs, CO 2 and ammonia since the various safety implications can be handled in a relatively straight-forward manner.

Stationary air conditioning

Stationary air conditioning systems includes small window and split units, multi-split systems and central chillers that provide cooling to air handlers. Most integral

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and split systems previously used R22 until R407C was introduced, but the larger manufacturers are now adopting R410A due to smaller components and marginal gains in efficiency. R290 is also being used because of its favourable environmental characteristics and good efficiency, and for similar reasons systems using CO 2 are being investigated. Although the efficiency of CO 2 in a split type air conditioner has been demonstrated to match that of an R410A system under most conditions (Jakobsen et al, 2006), the technology required to achieve comparable efficiencies at higher ambient temperatures (i.e., in the transcritical cycle) are likely to be costly – certainly until the market matures. Multi-split systems are following the trend of shifting from R407C to R410A for much the same reasons, but HCs are not viable because the significantly higher refrigerant charges invoke impractical safety measures prescribed by standards such as EN 378. Most chillers for air conditioning within Europe are positive displacement machines, using reciprocating, scroll or screw compressors. R22 had been the primary choice for these chillers, but the most common refrigerants are now R134a and R407C. Some manufacturers offer chillers using R290, R1270 and ammonia since their installation outside buildings means that conformity to safety requirements is easier. Heat pumps are used for heating occupancies and also to produce domestic hot water, and are in common use in central and northern Europe. These systems had almost exclusively used R22, but recently most manufacturers have offered units with a selection of refrigerants including R290, R407C and lately R410A.

4 Final Remarks

The Montreal Protocol which phases out CFCs and HCFCs initiated the significant research efforts into refrigerants and refrigeration technology, and subsequent environmental legislation arising from the Kyoto Protocol to reduce emissions of GHGs has continued to drive that research.

There is an adequate choice of both synthetic and natural refrigerants available for all types of systems and applications. HFCs are the most common fluids used in new systems throughout Europe, typically R134a, R404A, R407C and more recently R410A, and their uptake is largely due to convenience despite having a high GWP. Non-synthetic refrigerants – primarily ammonia (R717), carbon dioxide (R744) and HCs (R600a, R290, R1270) – are increasing in use because of their favourable environmental and performance characteristics. Compared to CFCs and HCFCs, use of these alternative refrigerants poses greater technical challenges, mainly including compatibility, efficiency and safety issues. The tendency until recently had been to adopt new refrigerants that possess similar pressure-temperature and operating characteristics as the ODSs they replace because of convenience in using existing system and component designs. However, the introduction of R600a, R410A and most significantly, CO 2, new systems are being designed in a fashion that departs from the conventional R12, R502 and R22 baselines.

Many obstacles exist that have resulted in a slow uptake of certain alternatives. These include actual technical barriers such as overcoming safety issues of

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flammable and/or toxic refrigerants, design of components for high pressure refrigerants and achieving certain efficiency baselines for refrigerants with poor thermophysical properties. Another form of barrier arises from the perception of the field-level industry where the consequence of certain characteristics (such as temperature glide or high operating pressure) are interpreted out of context. Similarly, market competition means that organisations with interests in a particular technology use a number of tactics to promote their own alternatives.

Finally, the mindset of the industry as a whole is one that expects a return to a standardised set of a small number of refrigerants for the majority of applications. However, it appears that the norm is actually a disparate group of various refrigerants that will continue to evolve over the next few decades at least.

Related MTP information

• BNXS21 Index of Key Data and Assumptions used by MTP • Briefing Note BNCR36 Direct emission of refrigerants. • Briefing Note BNCR37 Characteristics of refrigerants in relation to efficiency.

Appendix 1

Refrigerants with R-number designation and selected characteristics (EN 378)

R- Safety PL LFL GWP Composition NBP (°C) ODP number group (kg/m 3) (kg/m 3) (100 yr) R-11 R-11 (CFC) 24 A1 0.3 – 1 3800 R-12 R-12 (CFC) -30 A1 0.5 – 1 8100 R-12B1 R-12B1 (BCFC) -4 – 0.2 – 3 1300h R-13 R-13 (CFC) -81 A1 0.5 – 1 14000 R-13B1 R-13B1 (BFC) -58 A1 0.6 – 10 5400 R-14 R-14 (PFC) -128 A1 n/a – 0 6500 R-22 R-22 (HCFC) -41 A1 0.3 – 0.055 1500 R-23 R-23 (HFC) -82 A1 0.68 – 0 11700 R-30 R-30 (HCC) 40 B2 0.017 0.417 0 9 R-32 R-32 (HFC) -52 A2 0.061 0.306 0 650 R-50 R-50 (methane) -161 A3 0.006 0.032 1 21 R-113 R-113 (CFC) 48 A1 0.4 – 0.8 4800 R-114 R-114 (CFC) 4 A1 0.7 – 1 9800h R-115 R-115 (CFC) -39 A1 0.6 – 0.6 7200h R-116 R-116 (PFC) -78 A1 0.55 – 0 9200 R-123 R-123 (HCFC) 27 B1 0.1 – 0.02 90

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R- Safety PL LFL GWP Composition NBP (°C) ODP number group (kg/m 3) (kg/m 3) (100 yr) R-124 R-124 (HCFC) -12 A1 0.11 – 0.022 470 R-125 R-125 (HFC) -49 A1 0.39 – 0 2800 R-134a R-134a (PFC) -26 A1 0.25 – 0 1300 R-141b R-141b (HCFC) 32 B2 0.013 0.43 0.11 600 R-142b R-142b (HCFC) -10 A2 0.066 0.329 0.065 1800 R-143a R-143a (HFC) -47 A2 0.056 0.282 0 3800 R-152a R-152a (HFC) -25 A2 0.026 0.13 0 140 R-170 R-170 () -89 A3 0.008 0.038 0 3 R-1150 R-1150 (ethene) -104 A3 0.007 0.036 0 3 R-E170 R-E170 () -25 A3 0.013 0.064 0 - R-218 R-218 (PFC) -37 A1 0.44 – 0 7000 R-227ea R-227ea (HFC) -16 A1 0.49 – 0 2900 R-236fa R-236fa (HFC) -1 A1 0.59 – 0 6300 R-245fa R-245fa (HFC) 15 B1 0.19 – 0 950 R-290 R-290 () -42 A3 0.008 0.038 0 3 R-1270 R-1270 () -48 A3 0.008 0.040 0 3 R-365mfc R-365mfc (HFC) 40.1 – – – 0 890 R-43- 54.6 A1 – – 0 1500 10mee R-43-10mee (FC) R-C318 R-C318 (PFC) -6 A1 0.81 – 0 8700 R-600 R-600 () 0 A3 0.0086 0.043 0 3 R-600a R-600a () -12 A3 0.0086 0.043 0 3 R-601 R-601 () 36 A3 0.008 0.041 0 3 R-601a R-601a () 28 A3 0.008 0.041 0 3 R-717 R-717 (ammonia) -33 B2 0.00035 0.104 0 0 R-744 R-744 (carbon dioxide) -78 A1 0.07 – 0 1 R-401A R-22/152a/124 -34.4/-28.8 A1 0.3 – 0.037 970 R-401B R-22/152a/124 -35.7/-30.8 A1 0.34 – 0.04 1060 R-401C R-22/152a/124 -30.5/-23.8 A1 0.24 – 0.03 760 R-402A R-125/290/22 -49.2/-47.0 A1 0.33 – 0.021 2250 R-402B R-125/290/22 -47.2/-44.9 A1 0.32 – 0.033 1960 R-403A R-290/22/218 -44.0/-42.3 A1 0.33 – 0.041 2520 R-403B R-290/22/218 -43.8/-42.3 A1 0.41 – 0.031 3570 R-404A R-125/143a/134a -46.6/-45.8 A1 0.48 – 0 3260 R-405A R-22/152a/142b/C318 -32.9/-24.5 A1 0.26 – 0.028 4480 R-406A R-22/600a/142b -32.7/-23.5 A2 0.13 0.302 0.057 1560 R-407A R-32/125/134a -45.2/-38.7 A1 0.33 – 0 1770 R-407B R-32/125/134a -46.8/-42.4 A1 0.35 – 0 2280 R-407C R-32/125/134a -43.8/-36.7 A1 0.31 – 0 1520

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R- Safety PL LFL GWP Composition NBP (°C) ODP number group (kg/m 3) (kg/m 3) (100 yr) R-407D R-32/125/134a -39.4/-32.7 A1 0.41 – 0 1420 R-407E R-32/125/134a -42.8/-35.6 A1 0.40 – 0 1360 R-408A R-125/143a/22 -45.5/-45.0 A1 0.41 – 0.026 2650 R-409A R-22/124/142b -35.4/-27.5 A1 0.16 – 0.048 1290 R-409B R-22/124/142b -36.5/-29.7 A1 0.17 – 0.048 1270 R-410A R-32/125 -51.6/-51.5 A1 0.44 – 0 1720 R-410B R-32/125 -51.5/-51.4 A1 0.43 – 0 1830 R-411A R-1270/22/152a -39.7/-37.2 A2 0.04 0.186 0.048 1330 R-411B R-1270/22/152a -41.6/-41.3 A2 0.05 0.239 0.052 1410 R-412A R-22/218/142b -36.4/-28.8 A2 0.07 0.329 0.055 1850 R-413A R-218/134a/600a -29.3/-27.6 A2 0.08 0.375 0 1770 R-414A R-22/124/600a/142b -34.0/-25.8 A1 0.08 – 0.045 1200 R-414B R-22/124/600a/142b -34.4/-26.1 A1 0.07 – 0.042 1100 R-415A R-22/152a -37.5/-34.7 A1 0.3 – 0.037 970 R-416A R-134a/124/600 -23.4/-21.8 A1 – – 0.009 950 R-417A R-125/134a/600 -38.0/-32.9 A1 0.15 – 0 1950 R-500 R-12/152a -33.5 A1 0.4 – 0.74 6000 R-501 R-22/12 -41.0 A1 0.38 – 0.29 3150 R-502 R-22/115 -45.4 A1 0.45 – 0.33 4400 R-503 R-23/13 -88.7 A1 0.35 – 0.6 13100 R-504 R-32/115 -57.0 A1 0.14 – 0.31 4040 R-505 R-12/31 -30.0 A1 0.14 – 0.78 n/k R-506 R-31/114 -12.0 A1 0.14 – 0.45 n/k R-507A R-125/143a -46.7 A1 0.49 – 0 3300 R-508A R-23/116 -86.0 A1 0.22 – 0 11860 R-508B R-23/116 -88.3 A1 0.2 – 0 11850

Changes from version 1.1 No changes

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