SAQA All qualifications and part qualifications registered on the National Qualifications Framework are public property. Thus the only payment that can be made for them is for service and reproduction. It is illegal to sell this material for profit. If the material is reproduced or quoted, the South African Qualifications Authority (SAQA) should be acknowledged as the source.
SOUTH AFRICAN QUALIFICATIONS AUTHORITY 
REGISTERED UNIT STANDARD THAT HAS PASSED THE END DATE: 

Design hot and cold water reticulation systems for air-conditioning and refrigeration applications 
SAQA US ID UNIT STANDARD TITLE
9451  Design hot and cold water reticulation systems for air-conditioning and refrigeration applications 
ORIGINATOR
SGB Air-conditioning Refrigeration and Ventilation 
PRIMARY OR DELEGATED QUALITY ASSURANCE FUNCTIONARY
-  
FIELD SUBFIELD
Field 06 - Manufacturing, Engineering and Technology Engineering and Related Design 
ABET BAND UNIT STANDARD TYPE PRE-2009 NQF LEVEL NQF LEVEL CREDITS
Undefined  Regular  Level 5  Level TBA: Pre-2009 was L5  10 
REGISTRATION STATUS REGISTRATION START DATE REGISTRATION END DATE SAQA DECISION NUMBER
Passed the End Date -
Status was "Registered" 		 2001-06-13  2004-06-13  SAQA 0836/01 
LAST DATE FOR ENROLMENT LAST DATE FOR ACHIEVEMENT
2005-06-13   2008-06-13  

In all of the tables in this document, both the pre-2009 NQF Level and the NQF Level is shown. In the text (purpose statements, qualification rules, etc), any references to NQF Levels are to the pre-2009 levels unless specifically stated otherwise.  

This unit standard does not replace any other unit standard and is not replaced by any other unit standard. 

PURPOSE OF THE UNIT STANDARD 
  • Select the most suitable system of water reticulation for an application.
  • Determine the sizes of water pipes used to convey hot, chilled or condenser water for air-conditioning or refrigeration systems.
  • Make a piping layout, recommend installation methods and select the essential, commonly used accessories required for water distribution and balancing.
  • Determine the pressure loss and pump duty for a system.
  • Select the pump for the duty required. 
    		•

    LEARNING ASSUMED TO BE IN PLACE AND RECOGNITION OF PRIOR LEARNING 
    Interpret architectural and refrigeration and air-conditioning plant layout drawings and sketches.
    Explain the operation of vapour compression refrigeration systems. Demonstrate knowledge of water piping systems, its components, accessories and controls for refrigeration, air-conditioning installations. Explain the need for water treatment and the methods and equipment used. Demonstrate knowledge of building construction and building services. Identify insulation methods and materials for piping as applicable to refrigeration and air-conditioning. List the commonly applied air-conditioning systems and explain their application. 

    UNIT STANDARD RANGE 
    Hot and cold water systems for air-conditioning and refrigeration applications. 

    Specific Outcomes and Assessment Criteria: 

    SPECIFIC OUTCOME 1 
    Recommend type of water reticulation system & size of piping to convey water / water/glycol mixtures 
    OUTCOME NOTES 
    Recommend the type of water reticulation system and size of piping to convey water or water/glycol mixtures. 

    ASSESSMENT CRITERIA     

    ASSESSMENT CRITERION 1 
    1. The different types of water reticulation systems are named, explained and the selection is justified. 
    ASSESSMENT CRITERION RANGE 
    The once through, the open and closed reticulation and the direct return and reverse return systems.
     

    ASSESSMENT CRITERION 2 
    2. The various available materials for piping are listed and a selection is made and justified. 

    ASSESSMENT CRITERION 3 
    3. The recommended water velocities for different applications are listed and discussed. 

    ASSESSMENT CRITERION 4 
    4. The recommended pipe friction rates for different applications are listed and discussed. 

    ASSESSMENT CRITERION 5 
    5. The expansion tank type and position is determined correctly. 

    SPECIFIC OUTCOME 2 
    Determine the required pipe sizes. 

    ASSESSMENT CRITERIA     

    ASSESSMENT CRITERION 1 
    1. A sketch showing the piping layout is drawn correctly. 

    ASSESSMENT CRITERION 2 
    2. The water quantities in the pipe sections are correctly entered. 

    ASSESSMENT CRITERION 3 
    3. The correct pipe sizing charts are used. 

    ASSESSMENT CRITERION 4 
    4. All piping is correctly sized considering all design parameters. 
    ASSESSMENT CRITERION RANGE 
    Length of parallel circuits, pipe size reductions, future extensions.
     

    SPECIFIC OUTCOME 3 
    Select the required fittings and accessories for flow control and maintenance. 

    ASSESSMENT CRITERIA     

    ASSESSMENT CRITERION 1 
    1. The required fittings are selected correctly. 
    ASSESSMENT CRITERION RANGE 
    All fittings including but not limited to bends, tees, unions, reducers, drains, pipe supports, anti vibration supports, etc.
     

    ASSESSMENT CRITERION 2 
    2. The required accessories for flow control are selected correctly. 
    ASSESSMENT CRITERION RANGE 
    Control valves, regulating valves, orifices, flow meters, flow indicators.
     

    ASSESSMENT CRITERION 3 
    3. The required insulation methods and insulation materials are selected correctly. 

    ASSESSMENT CRITERION 4 
    4. The required accessories for ease of maintenance are selected correctly. 
    ASSESSMENT CRITERION RANGE 
    All accessories including but not limited to: shut-off valves, expansion tank, drains, pressure gauges, thermometers, etc.
     

    SPECIFIC OUTCOME 4 
    Determine the pump duty. 

    ASSESSMENT CRITERIA     

    ASSESSMENT CRITERION 1 
    1. All pressure losses in the system sections are calculated or determined correctly. 
    ASSESSMENT CRITERION RANGE 
    Losses in piping, fittings, accessories and equipment and static head.
     

    ASSESSMENT CRITERION 2 
    2. The total pressure loss in the entire system is determined correctly. 
    ASSESSMENT CRITERION RANGE 
    (series and parallel circuits to be considered).
     

    ASSESSMENT CRITERION 3 
    3. Consideration is given to reselecting pipe sections to reduce costs or pressure losses. 

    ASSESSMENT CRITERION 4 
    4. The pump duty is correctly specified. 

    SPECIFIC OUTCOME 5 
    Select the pump required for the system. 

    ASSESSMENT CRITERIA     

    ASSESSMENT CRITERION 1 
    1. The most suitable type of pump is selected. 

    ASSESSMENT CRITERION 2 
    2. The correct pump curves are used. 

    ASSESSMENT CRITERION 3 
    3. The most suitable pump is selected considering all design parameters. 
    ASSESSMENT CRITERION RANGE 
    Efficiency, maximum capacity, pressure, pump-shaft and impeller materials, type of drive, motor size and type.
     

    SPECIFIC OUTCOME 6 
    Write a specification. 

    ASSESSMENT CRITERIA     

    ASSESSMENT CRITERION 1 
    1. Pipe sizes, materials and types are correctly specified. 

    ASSESSMENT CRITERION 2 
    2. All accessories are correctly specified. 

    ASSESSMENT CRITERION 3 
    3. The insulation materials and thickness is correctly specified. 

    ASSESSMENT CRITERION 4 
    4. Construction and installation methods are correctly specified. 

    ASSESSMENT CRITERION 5 
    5. A neat diagrammatic sketch of the system is made. 


    UNIT STANDARD ACCREDITATION AND MODERATION OPTIONS 
    Any person wishing to be assessed against this unit standard may apply to an assessment agency, assessor or provider institution accredited by the relevant ETQA, who may appoint a moderator to be present at the assessment.

    The assessor must have knowledge and experience of air-conditioning or refrigeration. 

    UNIT STANDARD ESSENTIAL EMBEDDED KNOWLEDGE 
    Names, functions and characteristics of water reticulation equipment and accessories
    Implications of selecting unsuitable operating parameters for water reticulation equipment and accessories
    The effect of selection of equipment on the capital and running cost of the plant 


    Critical Cross-field Outcomes (CCFO): 

    UNIT STANDARD CCFO IDENTIFYING 
    Identify and solve problems
  • Interpret drawings in order to obtain information required to solve problems and carry out tasks 
    		•

    UNIT STANDARD CCFO COLLECTING 
    Collect, analyze, organize and critically evaluate information
  • Interpreting manufacturer`s specifications and instructions
  • Interpret graphs and tables 
    		•

    UNIT STANDARD CCFO SCIENCE 
    Use science and technology effectively and critically
  • Selecting the correct water reticulation method and system 
    		•

    UNIT STANDARD CCFO DEMONSTRATING 
    Demonstrate an understanding of the world as a set of related systems
  • Be aware of the effect of pipe sizing and maintenance and running costs 
    		•

    UNIT STANDARD NOTES 
    On assessment the learner must be provided with all the details and catalogues required. 

    QUALIFICATIONS UTILISING THIS UNIT STANDARD: 
      ID QUALIFICATION TITLE PRE-2009 NQF LEVEL NQF LEVEL STATUS END DATE PRIMARY OR DELEGATED QA FUNCTIONARY
    Core  20722   National Diploma: Air Conditioning, Refrigeration and Ventilation  Level 5  Level TBA: Pre-2009 was L5  Passed the End Date -
    Status was "Registered"     		 2004-06-13  MERSETA 


    PROVIDERS CURRENTLY ACCREDITED TO OFFER THIS UNIT STANDARD: 
    This information shows the current accreditations (i.e. those not past their accreditation end dates), and is the most complete record available to SAQA as of today. Some Primary or Delegated Quality Assurance Functionaries have a lag in their recording systems for provider accreditation, in turn leading to a lag in notifying SAQA of all the providers that they have accredited to offer qualifications and unit standards, as well as any extensions to accreditation end dates. The relevant Primary or Delegated Quality Assurance Functionary should be notified if a record appears to be missing from here.
     
    NONE 


    All qualifications and part qualifications registered on the National Qualifications Framework are public property. Thus the only payment that can be made for them is for service and reproduction. It is illegal to sell this material for profit. If the material is reproduced or quoted, the South African Qualifications Authority (SAQA) should be acknowledged as the source.