Refrigeration Practice NCV Level 3 — Document

November 2019 — NCV Level 3 — Refrigeration Practice

NCV Level 3 2019 NCV Engineering

↓ Download PDF 📄 302.1 KB

Preparing document

📋 Document Analysis

🎯 1 marks ⏱️ 3h 📄 7 pages 📝 46 items found

See full analysis

Questions — A Preview of What to Expect in the Document

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 —

1.1What can be done to increase the pressure in a gas? Increase the volume Increase the temperature and the

1.2The motor used in household refrigerators is DC series motor

1.3

1.4highly toxic and inflammable non toxic

1.5Where does the lowest temperature occur in a vapour compression cycle? ondenser vaporator

1.6In a refrigeration cycle, the flow of the refrigerant is controlled by the compressor

1.7At lower temperatures and pressures, the latent heat of vaporisation of a refrigerant occur in the compressor

1.8The high sensible heat high latent heat

1.9The moisture in a refrigerant is removed by filter dryer evaporator

1.10

Q2— Section header —

2.1State the first law of thermodynamics. (2\

2.2What is the difference between sensible heat and latent heat (4\

2.3

2.4

2.5A refri gerant cylinder with a mass of 93 kg is lifted through a vertical height of 78 m by a light cable in 11s at a constant velocity. Calculate the following:

2.5.1Work done to lift the mass in oules

2.5.2

2.6Define the term airflow. (2\ [17] &# &.48:::9741.,+** (6030053\17

Q3— Section header —

3.1FIGURE 1: PVC CABLE

3.1.1What is the function of PVC (polyvinyl chloride\electrical cables?

3.1.2

3.2Describe trunking as a method used in electrical cable construction. (2\

3.3Which FOUR basic steps w ould you follow to isolate an earth leakage problem? (4\

3.4FIGURE 2: SIMPLE TRANSFORMER

3.4.1Explain how a trans former works. (3\

3.4.2State the function of a transformer. (2\

3.5What is the function of a surge protection device? (2\

3.6What is a circuit breaker (2\

3.7What is a conduit (2\

3.8Name TWO disadvantages of using metal conduit. (2\ [23] (6030053\23

Q4— Section header —

4.1Laboratory analysis of the refrigeration oil may be desired. Explain how you can obtain refrigeration oil from a refrigeration system. (4\

4.2It is important to use the correct refrigeration oil in the refri geration system. Explain the consequences of using incorrect refrigeration oil in the refrigeration system. (2\

4.3Give an appropriate name for each of the following refrigeration tools

4.3.6

4.4Refrigeration compressor failure is a big, expensive problem in the refrigeration industry. List SEVEN causes of refrigeration compressor failure in the refrigeration industry. (7\ [25]25

Q5— Section header —

5.1What does the term ransfer switch or changeover switch mean? (2\

5.2List and describe the TWO requirements regarding refrigerant detectors according to SANS 10147 (4\

5.3List and describe the SEVEN requirements of ventilating plant rooms in accordance with SANS 10147 (14\ [20]20

Q6— Section header —

6.1Define water treatment (2\

6.2What is the effect of drinking non treated water on human beings? (3\ [5] TOTAL: 1005

Mark Allocation

Total100 marks

Sections10 + 17 + 23 + 25 + 20 + 5 = 100 marks

Paper information

TitleDocument

SubjectRefrigeration Practice

LevelNCV Level 3

Document typeQuestion paper

Year2019

MonthNovember

Pages7

Downloads4

Examination context

Decade2010s

Years ago7y

SeasonSpring (SH)

Start dayFriday

Exam periodNovember 2019

Days since exam2,537

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 size302.1 KB

Pages7

Archived on8 September 2026

File age47d

ContributorFreeMode

Fingerprint45FEDC0F635A

Questions and learner discussion

No questions or discussions have been posted yet.