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

More documents

Recommendations

Info

1 Environmental Impact countries which rely heavily on hydro-electricity or other renewable energy resources (such as solar, wind, geothermal, and biomass), or nuclear power, there are minimal emissions of CO2 per kWh of electricity consumed. In countries that use carbon-intensive electricity production, emissions can be around 1 kg of CO2 per kWh. In these countries, the energy used is often the dominant contribution to equipments’ GHG emissions. Therefore, it is important to also improve and maintain the efficiency of RAC equipment over its entire lifetime. Certain concepts are often used to evaluate the overall lifetime GHG impact of RAC systems. These include a variety of names: Total Equivalent Warming Impact (TEWI), Life Cycle Climate Performance (LCCP), and Life Cycle Warming Impact (LCWI), amongst others. Essentially, all these concepts are the same: they add the total equivalent GHG emissions from different sources together, over the lifetime of the equipment. The purpose of doing this is often used to compare different technologies, and more constructively, to identify which aspects of the equipment could be most effectively optimised to help reduce its global warming impact. Lastly, it is of utmost importance to carry out such evaluations with attention to detail, since there are myriad assumptions involved, and as such it is easy to draw erroneous conclusions. The Earth has a natural temperature control system. Certain atmospheric gases are vital in this system and are known as greenhouse gases. The Earth’s surface becomes warm and as a result of incoming solar radiation and then emits infrared radiation. The greenhouse gases trap some of the infrared radiation thus warming the atmosphere. Naturally occurring greenhouse gases include water vapour, carbon dioxide, ozone, methane and nitrous oxide: together they create a natural greenhouse effect. Without this phenomenon the Earth’s average temperature would be more than 30°C (60 °F) lower throughout the year. Global warming might also slow down the ozone layer’s recovery; despite the temperature rise in the troposphere, the air might even cool down in the stratosphere, which is favourable to the depletion of the ozone layer. The heat budget is dynamic – it is changing. For example: at the time of the dinosaurs there was more carbon dioxide in the atmosphere, trapping more heat, creating a higher planetary temperature. This is an example of a feedback system. Activity Affect Increase Earth’s Temperature Cutting down forests will: √ 26 Decrease Earth’s Temperature A major volcanic eruption will: √ √ Burning fossil fuels leading to increased carbon dioxide in the atmosphere will: The addition of CFCs will: √ The addition of HCFCs will: √ The addition of HFCs will: √ √ (May also offer some cooling as particles in the atmosphere reflect the sun’s rays)
1 Environmental Impact Timeline activity An overview of refrigerant development, phase out CFC and Phase out HCFC are given here: 19th Century Refrigeration technology using the thermodynamic vapour compression cycle technology was first developed in the middle of the 19th Century. The technology used four basic components (compressor, condenser, evaporator and device expansion) and a working fluid, called a refrigerant. Since then, the RAC industry has evolved significantly, and has been present in many social sectors. 1930s CFC and HCFC refrigerants were developed and have been used in the 1930s and 1940s. 1970s During the 1970s CFC and HCFC refrigerants were found to be directly connected to a global environmental problem: the depletion of the ozone layer. 1987 CFC and HCFC are scheduled to be eliminated by the Montreal Protocol, an international agreement established in 1987. As well as contributing to the depletion of the ozone layer, CFCs and HCFCs are strong greenhouse gases, thus contributing to the global warming process. Since the establishment of Montreal Protocol, the refrigeration industry has been searching substitutes to CFCs and HCFCs refrigerants. At the same time, the industry has been developing ways to conserve these refrigerants, making the installations more leak-tight, adopting procedures for recovery and treatment of refrigerants for re-use, and converting installations to use zero ozone depleting substances (ODS) and low-global warming refrigerants. These procedures are now part of the socalled good practices of RAC servicing, and this manual has the objective of summarise them, helping technicians to deal with the upcoming challenges within the field of RAC. 2006 Global HCFC production was 34,400 ODP tonnes and approximately 75% of global HCFC use was in air-conditioning and refrigeration sectors. The main HCFC used is R22 or chlorodifluoromethane. 2007 At the 20th anniversary meeting of the Montreal Protocol on Substances that Deplete the Ozone Layer, in Montreal, agreement was reached to adjust the Montreal Protocol’s schedule to accelerate the phase-out of production and consumption of HCFCs. This decision will result in a significant reduction in ozone depletion, with the intention of simultaneously reducing the global warming impact. In addition to the HCFC accelerated phaseout schedules, the 2007 Meeting of the Parties of the Montreal Protocol approved a decision to encourage Parties to promote the selection of alternatives to HCFCs that minimise environmental impacts, in particular impacts on climate, as well as meeting other health, safety and economic considerations (Decision XIX/6: Adjustments to the Montreal Protocol with regard to Annex C, Group I, substances or so-called HCFCs). 27
Page 1 and 2: 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: 1 Environmental Impact The greenhou
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 and 62: 3 Refrigerant Management Handling o
Page 63 and 64: 3 Refrigerant Management Recovery c
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 77 and 78:
3 Refrigerant Management CHAPITRE 3
Page 79 and 80:
3 Refrigerant Management PAGE 22 Ex
Page 81 and 82:
3 Refrigerant Management CHAPITRE 3
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
Page 113 and 114:
5 Retrofitting General retrofitting
Page 115 and 116:
5 Retrofitting procedures that you
Page 117 and 118:
5 Retrofitting MVAC retrofitting pr
Page 119 and 120:
5 Retrofitting Although, in general
Page 121 and 122:
5 Retrofitting Further reading UNEP
Page 123 and 124:
6 Summary 6.1. Overview of refriger
Page 125 and 126:
6 Safe Refrigerant Handling Oxygen
Page 127 and 128:
6 Safe Refrigerant Handling The com
Page 129 and 130:
6 Safe Refrigerant Handling • Nev
Page 131 and 132:
6 Safe Refrigerant Handling Safe ha
Page 133 and 134:
6 Safe Refrigerant Handling leak de
Page 135 and 136:
6 Safe Refrigerant Handling • Lea
Page 137 and 138:
6 Safe Refrigerant Handling Storage
Page 139 and 140:
6 Safe Refrigerant Handling Recomme
Page 141 and 142:
6 Safe Refrigerant Handling 3 - Sho
Page 143 and 144:
Glossary Glossary Absolute pressure
Page 145 and 146:
Glossary Fossil fuels Carbon-based
Page 147 and 148:
Glossary hole in late 1985, governm
Page 149 and 150:
Glossary Sealed system A refrigerat
Page 151 and 152:
Acknowledgements Acknowledgements I
Page 153:
Copyright Copyright © United Natio
show all

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

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?