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Refrigeration Fundamentals of Refrigeration

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Refrigeration Fundamentals of Refrigeration Table of Contents Introduction ........................................................................................................................... 1 Major Seminar Topics ........................................................................................................................................ 1 Issues for Refrigeration Facilities ........................................................................................ 3 Users of Refrigeration ........................................................................................................................................ 3 Refrigeration Classifications ............................................................................................................................... 4 Typical Supermarket Electrical Usage ............................................................................................................... 5 Typical Commercial and Industrial Electrical Usage .......................................................................................... 5 Integrated Demand Side Management (IDSM) .................................................................................................. 6 What is Title 24?............................................................................................................................................... 22 Reasons for Using Refrigeration ...................................................................................................................... 23 Refrigeration Units in California ....................................................................................................................... 27 Benefits of Refrigeration ................................................................................................................................... 27 AHRI Standard 1200 ........................................................................................................................................ 28 Fundamentals of Refrigeration .......................................................................................... 39 A Few Terms and Concepts ............................................................................................................................. 39 Refrigeration Basics ......................................................................................................................................... 40 Vapor Compression System ............................................................................................................................ 43 Refrigeration System Divided Into Two Parts .................................................................................................. 49 Refrigeration Cycle ........................................................................................................................................... 50 A Conventional Refrigeration System .............................................................................................................. 53 Parallel or Multiplex Refrigeration System ....................................................................................................... 54 It’s Only A Matter Of Size ................................................................................................................................. 56 Sizing Multiple Compressors in Parallel Rack Systems ................................................................................... 57 Check Your Understanding .............................................................................................................................. 58 Refrigeration System Components ................................................................................... 59 Compressor Design.......................................................................................................................................... 60 Reciprocating Compressors ............................................................................................................................. 62 Screw Compressors ......................................................................................................................................... 63 Scroll Compressors .......................................................................................................................................... 65 Compressor Summary ..................................................................................................................................... 70 Condensers and Heat Rejection Techniques .................................................................................................. 73 Air-Cooled Condensers .................................................................................................................................... 74 Water-Cooled Condensers ............................................................................................................................... 75 Evaporative Condensers .................................................................................................................................. 76 Condenser Efficiency ....................................................................................................................................... 78 Exercise: Condenser Financial Analysis .......................................................................................................... 83 Evaporators ...................................................................................................................................................... 89 Evaporator Fan Controller for Walk-in Coolers ................................................................................................ 92 Expansion Valves ............................................................................................................................................. 94 Refrigerants ......................................................................................................................... 97 A Brief Chemistry Lesson... .............................................................................................................................. 97 Refrigerant Chemical Composition .................................................................................................................. 98 Safety Classifications ..................................................................................................................................... 100 Efficient Technologies for Commercial Refrigeration i Naming the Refrigerants ................................................................................................................................ 101 Pure Refrigerants and Blends ........................................................................................................................ 108 Glide ............................................................................................................................................................... 109 Refrigerant Choices for Commercial Refrigeration ........................................................................................ 111 Interim Refrigerant Alternatives ...................................................................................................................... 112 R-22 Compared with R-404A and R-507 ....................................................................................................... 122 New Refrigerant: Hydrofluoroolefins (HFOs) ................................................................................................. 123 Retrofit Options for Existing Systems ............................................................................................................. 124 Options for New Refrigeration Equipment ...................................................................................................... 128 Natural Refrigerants ....................................................................................................................................... 130 Indirect Refrigeration Systems ....................................................................................................................... 131 Carbon Dioxide in Indirect Cascade Refrigeration Systems .......................................................................... 132 Refrigerant Management Program Rules ....................................................................... 135 Regulated Refrigerants .................................................................................................................................. 139 Commercial Refrigerant Research Project (A Case In Point) ......................................................................... 140 Test Result Tables ......................................................................................................................................... 145 Refrigerant Tables .......................................................................................................................................... 146 Methods For Improving Refrigeration System Efficiency ............................................. 153 A Brief Physics Lesson... ................................................................................................................................ 154 Condensate Flashing (Flash gas) or Incomplete Condensing ....................................................................... 161 Subcooling .....................................................................................................................................................
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