Refrigeration Practice NCV Level 3 — Document
November 2018 — NCV Level 3 — Refrigeration Practice
NCV Level 3
2018
NCV Engineering
Preparing document
📋 Document Analysis
See full analysis
Questions — A Preview of What to Expect in the Document
49
This section provides a quick preview of questions from the document. It may not display every question or the complete wording of each one. For the full content, including diagrams, tables and other information, view the original PDF above.
Q1— Section header —
1.1Define the specific heat capacity of a substance (2\
1.2The three phase in which matter can exist are solid, liquid, vapour or gas. Choose a description from COLUMN B that matches a description in COLUMN A. Write only the letter (A E\next to the question number
1.2.5\ the ANSWER BOOK. COLUMN A COLUMN B
1.2.5Heat of condensation Latent heat of ice Heat of fusion Heat of vapori ation Heat of sublimation
1.32 630 J is supplied to condense 1,8 kg of refrigerant (R22\vapour. The specific heat of R22 refrigerant is 1,03 kj/kg and the initial temperature is 322 K. Calculate the following:
1.3.1Increase in temperature
1.3.2
1.4What is energy (2\
1.5A refrigerant cylinder with a mass of 35 kg is lifted through a vertical height of 32 m by a light cable in 8s at a constan t velocity. Calculate the following:
1.5.1The work done to lift the mass/cylinder
1.5.2
1.6Compare the following terms, work and energy and indicate their similarities. (2\
1.7A gauge on a vessel rea ds 302 Kpa. If the atmospheric pressure is 88 Kpa, calculate the absolute pressure inside the vessel. (2\
1.8Calculate the mass flow through the compressor if the volume flow is 0,8 /s and the specific volume of the gas is 0,06 m /kg. (2\ [25] (6030053\25
Q2— Section header —
2.1What is fusible plug (2\
2.2As a refrigeration mechanic, you become aware that a compressor of a refrigeration plant does not stop (runs continuously\ Give THREE possible causes of such condition. (3\
2.3Give THREE corr ective actions to be taken in order to overcome the problem
Q2— Section header —
2.4Give the specific term of the following:
2.4.1A unit where the components of a refrigeration system are packaged together in a factory.
2.4.2
3.1Refrigerants are categorised into groups in accordance with their dominant characteristics. Give each group a nd their dominant characteristic/s. (8\
3.2What is the objective of SANS 10147? (6\
3.3In which group does ammonia refrigerant belong? (1\ [15]15
Q4— Section header —
4.1Identify the following symbols and write the correct name next to the question number (4.1.1
4.1.3\n the ANSWER BOOK.
4.1.3
4.2Name THREE main component s which form part of a condensing unit of a refrigeration system. (3\
4.3Draw a complete load diagram of the above condensing unit by indicating the load and other accessories such as: Current type starting with relay, overload, compressor terminals , fan motor, voltmeter and ammeter across the
4.4What kind of load is the fan motor? (1\
Q4— Section header —
4.6Your supervisor has requested you to test the compressor motor and your finding s are as follows: Common (C\ and the body of the compressor = 0 Running winding (R\ and the body of the compressor = 34 Starting winding (S\nd the body of the compressor = 25
4.7List FOUR tools you would use if the compressor motor must be removed from the system/plant due to its failure. (4\
4.8List FOUR factors that must be considered when selecting a cable for a ny specific application. (4\ [25]25
Q5— Section header —
5.1List FOUR types of expansion devices/valves that are used in refrigeration systems. (4\
5.2State the name of a device which senses the temperature within the cabinet of a refrigerator/freezer an d in turn acts to control the refrigeration circuit. (1\
5.3It is important to obtain as much information as possible when one enters into a refrigeration plant. State TWO reasons why service records for the plant should be inspected prior to wo rk. (2\
5.4Rearrange the following procedure in the correct alphabetical order (A E\for dismantling the refrigeration system. Remove the refrigerant
5.5The following fault is diagnosed during fault finding on site. The entire plant fails to start.
5.5.1Give FOUR possible causes of the fault.
5.5.2Give FOUR reme
Q5— Section header —
Q6— Section header —
6.1Name the THREE water related problems that appear in the system
6.2When metals are destr oyed by chemicals or electrochemical means, what would you call this process? (2\ [5] TOTAL: 1005
Mark Allocation
Total100 marks
Sections25 + 15 + 25 + 20 + 5 = 90 marks
Paper information
TitleDocument
SubjectRefrigeration Practice
LevelNCV Level 3
Document typeQuestion paper
Year2018
MonthNovember
Pages6
Downloads3
Examination context
Decade2010s
Years ago8y
SeasonSpring (SH)
Start dayThursday
Exam periodNovember 2018
Days since exam2,901
About Refrigeration Practice examination preparation
This TVET examination resource can be used as part of a structured revision programme. Past papers are most useful when learners attempt questions independently, work within a realistic time limit, and review their answers afterwards.
How to use this resource for revision
A TVET past examination paper is most useful when it is treated as an active revision exercise. Try the questions yourself before checking the corresponding memorandum. Where you make an error, identify the reason — was it a knowledge gap, a calculation mistake, an interpretation issue, or an examination technique problem?
For stronger examination practice, complete the paper without unnecessary interruptions and keep track of the questions that take the most time. Afterwards, review the memorandum and separate knowledge gaps from mistakes caused by interpretation, calculation, structure, or examination technique.
understanding question requirements
applying subject knowledge
working under time constraints
checking answers
identifying revision priorities
A practical revision approach
Start by completing the resource without looking at the memorandum. Review incorrect and incomplete answers afterwards and make a short revision list based on the areas that caused difficulty.
File details
File size207 KB
Pages6
Archived on8 September 2026
File age46d
ContributorFreeMode
Fingerprint022342F80D9A
Questions and learner discussion
Log in to ask a question or leave a review.
No questions or discussions have been posted yet.