Manual for Refrigeration Servicing Technicians - UNEP - Division of ...

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3 Refrigerant Management Disposable and non-refillable cylinders Available on the market are a type of cylinder called “non-refillable” or “disposable” cylinders. These are sometimes used where the supply infrastructure is less comprehensive, and it is less costly for refrigerant suppliers who may expect their cylinders to become lost. From both an environmental and safety perspective, the use of disposable cylinders is considered to be very bad practice. These containers are generally discharged after use, resulting in a lot of refrigerant being released to the atmosphere. Furthermore, there are often attempts to re-use these cylinders (for example, through brazing new valves onto them to enable re-filling with refrigerant), despite such practices being forbidden. Also, they tend to be manufactured from thinner metal than the conventional, re-usable cylinders, rendering them more susceptible to rusting and mechanical damage over time. As such, their use is not recommended under any circumstances. In fact they are already prohibited in many countries, such as the European Union member states and Australia and Canada. Other countries are also working to implement similar rules. Mandating the use of returnable, refillable containers was implemented as a key measure to reduce GHG emissions by eliminating the possibility of the eventual release of the residual product that unavoidably remains in disposable refrigerant containers. These regulations had support from the major refrigerant manufacturers and industry trade associations. If a disposable cylinder has been used, before disposing of it, it should be properly emptied. This requires the remaining refrigerant to be recovered until the pressure has been reduced to pressure of approximately 0.3 bar (absolute). The container’s valve must be closed at this time and the container marked as empty. The container is then ready for disposal. It is recommended that the cylinder valve should then be opened to allow air to enter, and the cylinder should be rendered useless (with the valve still open) by breaking off the valve or puncturing the container. This will avoid misuse of the container by untrained individuals. Used cylinders can be recycled with other scrap metal. Never leave used cylinders with residual refrigerant outdoors where the cylinder can rust. An abandoned cylinder will eventually deteriorate and could potentially explode. Refillable cylinders Refillable cylinders are the standard receptacles available for the storage and transportation of smaller quantities of refrigerant. They normally range in size from about 5 litres to 110 litres (approximately 5 to 100 kg of CFC, HCFC or HFC refrigerant). The cylinders are normally constructed from steel and have a combination valve, with separate ports for refrigerant removal, refrigerant filling and a pressure relief device. The port for refrigerant filling is normally locked so that only the refrigerant supplier can gain access. Some cylinders also have two separate removal ports: one for liquid and another for vapour, if the cylinder is fitted with a dip-tube. There is usually a metal collar around to the top of the cylinder to protect the valve from mechanical damage. Both the cylinder itself and the valve are usually subject to national regulations for their design, fabrication, and testing. 62
3 Refrigerant Management Recovery cylinders CHAPITRE 3 PAGE 6 Recovery cylinders are specifically intended for refrigerant that have been removed from refrigeration systems. The recovered refrigerant can then be re-used or sent for reclamation or disposal. The construction of the cylinders is normally very similar to a conventional refillable cylinder, except for two differences: one is that the cylinder valve has the refrigerant filling port enabled, so that refrigerant can be easily fed into the cylinder, and the second being the external marking. The cylinder shoulder and upper part is normally painted yellow, with the remainder of the cylinder body painted grey colour code is also applied to cylinder to indicate the type of recovered refrigerant, as shown in the illustration. Recovery Cylinder Vapor Liquid Recovery Cylinder Yellow Cutaway view Grey It is important to ensure that the recovery cylinder is only ever used for one type of refrigerant. This rule should be followed for two reasons: first, if different refrigerants are mixed, it may not be possible to separate them again for re-used, and secondly, mixing two or more refrigerants can result in a pressure that exceeds the pressure of either of the refrigerants added into the cylinder. For refrigeration technicians using recycling machines, it is suggested that the refrigeration technician utilise a ‘CLEAN’ recovery cylinder for recycled refrigerant and a ‘DIRTY’ recovery tank for recovered, but not recycled refrigerant. Marking the recovery tanks as clean and dirty will avoid contamination of otherwise clean refrigerant by putting clean refrigerant into a recovery tank that once held dirty refrigerant. 63
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Manual for Refrigeration Servicing
Page 3 and 4:
Introduction When to use the manual
Page 5 and 6:
Introduction The Factors affecting
Page 7 and 8:
Introduction How to assess conditio
Page 9 and 10:
Introduction Characteristics of Sel
Page 11 and 12: Introduction Another form of refere
Page 13 and 14: Introduction Choose your chapter Th
Page 15 and 16: 1 Environmental impact of refrigera
Page 17 and 18: 1 Environmental Impact The ozone la
Page 19 and 20: 1 Environmental Impact RADIATION FR
Page 21 and 22: 1 Environmental Impact The ozone la
Page 23 and 24: 1 Environmental Impact Effects of o
Page 25 and 26: 1 Environmental Impact The greenhou
Page 27 and 28: 1 Environmental Impact Timeline act
Page 29 and 30: 1 Environmental Impact Alternative
Page 31 and 32: 1 Environmental Impact The way forw
Page 33 and 34: 2 Refrigerants 2.1. Section objecti
Page 35 and 36: 2 Refrigerants Chemical properties
Page 37 and 38: 2 Refrigerants Safety characteristi
Page 39 and 40: 2 Refrigerants Types of refrigerant
Page 41 and 42: 2 Refrigerants Those with ozone dep
Page 43 and 44: 2 Refrigerants Those with zero ozon
Page 45 and 46: 2 Refrigerants Carbon dioxide (CO2,
Page 47 and 48: 2 Refrigerants Azeotropic Blends An
Page 49 and 50: 2 Refrigerants Using Refrigerant Bl
Page 51 and 52: 2 Refrigerants Lubricants Today, al
Page 53 and 54: 2 Refrigerants Refrigerants and app
Page 55 and 56: 2 Refrigerants Properties of most c
Page 57 and 58: 3 Refrigerants Content Management M
Page 59 and 60: 3 Refrigerant Management The majori
Page 61: 3 Refrigerant Management Handling o
Page 65 and 66: 3 Refrigerant Management Refrigeran
Page 67 and 68: 3 Refrigerant Management Refrigeran
Page 69 and 70: 3 Refrigerant Management Open Refri
Page 71 and 72: 3 Refrigerant Management CHAPITRE 3
Page 73 and 74: 3 Refrigerant Management Recycling
Page 75 and 76: 3 Refrigerant Management equipment
Page 79 and 80: 3 Refrigerant Management PAGE 22 Ex
Page 83 and 84: 3 Refrigerant Management Further re
Page 85 and 86: Summary This section will provide t
Page 87 and 88: 4 Servicing Practices Moisture Mois
Page 89 and 90: 4 Servicing Practices Non-condensab
Page 91 and 92: 4 Servicing Practices Evacuation A
Page 93 and 94: 4 Servicing Practices 7 - For large
Page 95 and 96: 4 Servicing Practices Pressure unit
Page 97 and 98: CHAPITRE 4 4PAGE 10 LEAK DETECTION
Page 99 and 100: 4 Servicing Practices Detection met
Page 101 and 102: 4 Servicing Practices CHAPITRE 4 PA
Page 103 and 104: 4 Servicing Practices Volumetric ch
Page 105 and 106: 4 Servicing Practices Electronic ch
Page 107 and 108: 4 Servicing Practices Why charge re
Page 109 and 110: 5 Retrofitting Content General retr
Page 111 and 112: 5 Retrofitting • Upon evaluation
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5 Retrofitting General retrofitting
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5 Retrofitting procedures that you
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5 Retrofitting MVAC retrofitting pr
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5 Retrofitting Although, in general
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5 Retrofitting Further reading UNEP
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6 Summary 6.1. Overview of refriger
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6 Safe Refrigerant Handling Oxygen
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6 Safe Refrigerant Handling The com
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6 Safe Refrigerant Handling • Nev
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6 Safe Refrigerant Handling Safe ha
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6 Safe Refrigerant Handling leak de
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6 Safe Refrigerant Handling • Lea
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6 Safe Refrigerant Handling Storage
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6 Safe Refrigerant Handling Recomme
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6 Safe Refrigerant Handling 3 - Sho
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Glossary Glossary Absolute pressure
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Glossary Fossil fuels Carbon-based
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Glossary hole in late 1985, governm
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Glossary Sealed system A refrigerat
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Acknowledgements Acknowledgements I
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Copyright Copyright © United Natio
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