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SOUTH AFRICAN QUALIFICATIONS AUTHORITY 
REGISTERED UNIT STANDARD THAT HAS PASSED THE END DATE: 

Plot air-conditioning processes on the psychometric chart and determine plant operating parameters 
SAQA US ID UNIT STANDARD TITLE
9516  Plot air-conditioning processes on the psychometric chart and determine plant operating parameters 
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 4  NQF Level 04  7 
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 is replaced by: 
US ID Unit Standard Title Pre-2009 NQF Level NQF Level Credits Replacement Status
116411  Plot air-conditioning processes on the psychometric chart and determine plant operating parameters  Level 4  NQF Level 04  7   

PURPOSE OF THE UNIT STANDARD 
Discuss and plot the psychrometric processes occurring in typical air-conditioning, refrigeration and evaporative cooling plants on the psychrometric chart.

Determine the entering and leaving conditions for the different plant component.

Determine the cooling and/or heating load, the humidification and/or de-humidification requirements and the air quantity required for satisfactory operation. 

LEARNING ASSUMED TO BE IN PLACE AND RECOGNITION OF PRIOR LEARNING 
  • Determine the properties of air from a psychrometric chart and carry out basic calculations involving heat and mass transfer.
  • List the commonly applied air-conditioning systems, and explain their operation. 
    		•

    UNIT STANDARD RANGE 
    Sensible cooling, latent cooling, total cooling, heating, humidification with sprays, humidification with steam, de-humidification by cooling, chemical de-humidification, heating and humidification, evaporative cooling and evaporative chilling processes.

    Operating parameters include entering and leaving temperatures, bypass factors and calculation of air quantities required for all processes. 

    Specific Outcomes and Assessment Criteria: 

    SPECIFIC OUTCOME 1 
    Plot the processes occurring in the plants on the psychrometric chart. 

    ASSESSMENT CRITERIA     

    ASSESSMENT CRITERION 1 
    1. The various processes are explained and reasons for use discussed. 

    ASSESSMENT CRITERION 2 
    2. The psychrometric chart for the correct altitude and temperature range is selected. 

    ASSESSMENT CRITERION 3 
    3. The state points for the conditions given are correctly plotted. 

    ASSESSMENT CRITERION 4 
    4. The entering and leaving conditions for the plant components are determined correctly. 

    ASSESSMENT CRITERION 5 
    5. The correct SI units and symbols are used. 

    ASSESSMENT CRITERION 6 
    6. Consequences of inaccurate plotting are listed and discussed. 

    SPECIFIC OUTCOME 2 
    Calculate the amount of sensible and latent heat added or removed. 

    ASSESSMENT CRITERIA     

    ASSESSMENT CRITERION 1 
    1. The amount of sensible, latent and total heat added or removed is calculated correctly from pre-determined or given state points. 

    ASSESSMENT CRITERION 2 
    2. The correct SI units and symbols are used. 

    SPECIFIC OUTCOME 3 
    Calculate the amount of moisture added or removed. 

    ASSESSMENT CRITERIA     

    ASSESSMENT CRITERION 1 
    1. The amount of water evaporated or vapour condensed is calculated correctly from pre-determined or given state points. 

    ASSESSMENT CRITERION 2 
    2. The correct SI units and symbols are used. 

    SPECIFIC OUTCOME 4 
    Calculate the air volume required for the various processes for a particular load. 

    ASSESSMENT CRITERIA     

    ASSESSMENT CRITERION 1 
    1. The air volume required to meet the particular load for the various processes is calculated correctly. 

    ASSESSMENT CRITERION 2 
    2. The correct SI units and symbols are used. 

    ASSESSMENT CRITERION 3 
    3. The consequences of inaccurate or faulty calculations are listed and explained. 


    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 
    The processes taking place in the various systems to provide the required internal conditions. 


    Critical Cross-field Outcomes (CCFO): 

    UNIT STANDARD CCFO IDENTIFYING 
    Identify and solve problems
  • Selecting the appropriate application 
    		•

    UNIT STANDARD CCFO COLLECTING 
    Collect, analyse, organise and critically evaluate information
  • Selecting the right information 
    		•

    UNIT STANDARD CCFO SCIENCE 
    Use science and technology effectively and critically
  • Use of psychrometric charts 
    		•

    UNIT STANDARD NOTES 
    This unit standard has been replaced by unit standard 116411, which is "Plot air-conditioning processes on the psychometric chart and determine plant operating parameters", Level 4, 7 credits.

    Commonly used psychrometric charts are to be provided. 

    QUALIFICATIONS UTILISING THIS UNIT STANDARD: 
      ID QUALIFICATION TITLE PRE-2009 NQF LEVEL NQF LEVEL STATUS END DATE PRIMARY OR DELEGATED QA FUNCTIONARY
    Elective  20721   National Certificate: Air Conditioning, Refrigeration and Ventilation  Level 4  NQF Level 04  Passed the End Date -
    Status was "Registered"     		 2004-06-13  Was MERSETA until Last Date for Achievement 


    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.