100+ Free C&G 2079-11 F-Gas Category I Practice Questions

Pass your City & Guilds 2079 Level 2 Award in F-Gas & ODS Regulations (Category I) exam on the first try — instant access, no signup required.

✓ No registration✓ No credit card✓ No hidden fees✓ Start practicing immediately

100+ Questions

100% Free

Loading practice questions...

Same family resources

Explore More City & Guilds UK Trade Qualifications

Continue into nearby exams from the same family. Each card keeps practice questions, study guides, flashcards, videos, and articles in one place.

2026 Statistics

Key Facts: C&G 2079-11 F-Gas Category I Exam

Exam Questions (MCQ)

City & Guilds 2079-11

60%

Passing Score (24/40)

City & Guilds

80 minutes

Time Limit

City & Guilds

Category I

Covers Any System Size

F-Gas Regulation

5 g/year

Detector Sensitivity Required

EU 517/2014

100

Free Practice Questions

OpenExamPrep

The City & Guilds 2079 Level 2 Award in F-Gas & ODS Regulations (Category I), qualification number 2079-11, is the legally required certificate of competence for handling fluorinated gases on stationary RACHP equipment in the UK. Category I is the broadest tier: it permits leak checking, recovery, installation, servicing and maintenance on systems of any refrigerant charge. The award is assessed by a 40-question on-screen multiple-choice exam lasting 80 minutes (60%, or 24 marks, to pass) together with a practical assessment, graded Pass/Fail. The theory covers the refrigeration cycle and p-h diagrams, refrigerants and the retained EU F-Gas Regulation 517/2014 (with CO2-equivalent leak-check thresholds and the HFC phase-down), system components, leak detection and repair, recovery/recycling/reclamation, environmental impact (GWP/ODP) and safety legislation. This free prep includes 100 research-based practice questions with explanations and an AI tutor.

Sample C&G 2079-11 F-Gas Category I Practice Questions

Try these sample questions to test your C&G 2079-11 F-Gas Category I exam readiness. Each question includes a detailed explanation. Start the interactive quiz above for the full 100+ question experience with AI tutoring.

1In a basic vapour-compression refrigeration cycle, which component absorbs heat from the space or product being cooled?

A.The condenser

B.The compressor

C.The evaporator

D.The expansion valve

Explanation: The evaporator is where low-pressure liquid refrigerant boils (evaporates), absorbing latent heat from the surrounding air or product and producing the cooling effect. The other three components either reject heat, raise pressure, or reduce pressure.

2Which of the four main refrigeration components raises the pressure and temperature of the refrigerant vapour?

A.The evaporator

B.The compressor

C.The condenser

D.The receiver

Explanation: The compressor draws in low-pressure superheated vapour from the evaporator and compresses it, raising both its pressure and temperature so that it can subsequently reject heat in the condenser. It is the only component that adds work to the system.

3What happens to the refrigerant as it passes through the expansion (throttling) device?

A.Its pressure and temperature both fall

B.Its pressure rises and temperature falls

C.Its pressure and temperature both rise

D.Its enthalpy increases sharply

Explanation: The expansion valve or capillary tube throttles high-pressure liquid to low pressure. Both pressure and temperature drop, and a small fraction of the liquid flash-evaporates. The process is essentially constant-enthalpy (isenthalpic), shown as a vertical line on the p-h diagram.

4On a pressure-enthalpy (p-h) diagram, the throttling process through the expansion valve is represented by which type of line?

A.A horizontal line of constant pressure

B.A vertical line of constant enthalpy

C.A curved line following the saturation dome

D.A diagonal line of constant entropy

Explanation: Throttling is an isenthalpic process: enthalpy is constant, so it appears as a vertical line on the p-h diagram (enthalpy on the horizontal axis, pressure on the vertical axis). Pressure drops while enthalpy stays the same.

5What is meant by 'superheat' in a refrigeration system?

A.The temperature of the refrigerant above its saturation temperature in the vapour state

B.The temperature of the liquid below its saturation temperature

C.The pressure rise across the compressor

D.The latent heat absorbed in the evaporator

Explanation: Superheat is the number of degrees the refrigerant vapour is heated above its saturation (boiling) temperature at the prevailing pressure. Adequate superheat at the compressor suction protects the compressor from liquid floodback (liquid slugging).

6What does 'sub-cooling' describe in the refrigeration cycle?

A.Cooling the vapour leaving the compressor

B.Cooling the liquid refrigerant below its saturation temperature

C.Heating the vapour above its saturation temperature

D.Reducing the suction pressure

Explanation: Sub-cooling is cooling the liquid refrigerant leaving the condenser to below its saturation temperature for the prevailing pressure. It ensures only liquid (not flash gas) enters the expansion device, improving capacity and efficiency.

7In the evaporator, refrigerant absorbs heat mainly by which mechanism?

A.Sensible heating of the vapour

B.Latent heat of vaporisation as the liquid boils

C.Heat of compression

D.Conduction through the receiver

Explanation: Inside the evaporator the low-pressure liquid refrigerant boils, absorbing latent heat of vaporisation from the air or product. Because a phase change absorbs a large amount of energy at constant temperature, this is what gives the system its cooling capacity.

8Which statement about the condenser in a vapour-compression system is correct?

A.It boils the refrigerant at low pressure

B.It rejects heat and condenses the high-pressure vapour to liquid

C.It reduces the refrigerant pressure

D.It compresses the refrigerant vapour

Explanation: The condenser receives hot, high-pressure superheated vapour from the compressor, de-superheats it, then condenses it to liquid by rejecting heat to the ambient air or water. The total heat rejected equals the cooling load plus the compressor work.

9On a p-h diagram, the area inside the curved 'saturation dome' represents refrigerant that is in which state?

A.Sub-cooled liquid only

B.Superheated vapour only

C.A mixture of liquid and vapour (two-phase)

D.Supercritical fluid

Explanation: The region under the saturation dome is the two-phase region, where liquid and vapour coexist. To the left of the dome the refrigerant is sub-cooled liquid; to the right it is superheated vapour. Evaporation and condensation both take place inside the dome at constant pressure.

10Why must liquid refrigerant be prevented from returning to the compressor suction?

A.Liquid is incompressible and can cause mechanical damage (liquid slugging)

B.Liquid lowers the system GWP

C.Liquid increases superheat

D.Liquid improves lubrication

Explanation: Liquid refrigerant is effectively incompressible, so if it reaches the compressor cylinders it can cause hydraulic shock or 'liquid slugging', damaging valves and bearings. Maintaining adequate suction superheat ensures only vapour enters the compressor.

About the C&G 2079-11 F-Gas Category I Exam

The City & Guilds 2079 Level 2 Award in F-Gas & ODS Regulations (Category I, qualification number 2079-11) is the UK certificate of competence required to legally handle fluorinated gases on stationary refrigeration, air-conditioning and heat-pump equipment. Category I covers all activities, leak checking, recovery, installation, service and maintenance, on systems of any charge size. Assessment is a 40-question on-screen multiple-choice exam (60% to pass) plus a practical assessment.

Assessment

40 on-screen (GOLA) multiple-choice questions over 80 minutes plus a practical assessment, graded Pass/Fail; 60% (24/40) is required on the theory paper. This practice bank is 100 selected-response items.

Time Limit

80 minutes (multiple-choice paper)

Passing Score

60% (24 of 40)

Exam Fee

Typically £300-£600 for the course, exam and certification (varies by centre) (City & Guilds (delivered through approved training centres))

C&G 2079-11 F-Gas Category I Exam Content Outline

18%

Refrigeration Cycle & p-h Diagrams

Vapour-compression cycle, the four main components, latent and sensible heat, superheat and sub-cooling, pressure-enthalpy diagrams, COP and basic thermodynamics

22%

Refrigerants, F-Gas & ODS Regulations

CFCs, HCFCs, HFCs, HFOs and blends, retained EU 517/2014, CO2-equivalent thresholds, service bans, HFC phase-down, certification and record keeping

14%

System Components

Compressors, condensers, evaporators, expansion devices, receivers, filter driers, sight glasses, accumulators, service valves, gauges and charging tools

16%

Leak Detection & Repair

Direct and indirect leak-check methods, statutory frequencies, detector sensitivity, fixed detection, pressure testing and follow-up checks after repair

12%

Recovery, Recycling & Reclamation

Recovering without venting, recovery cylinders and fill limits, avoiding cross-contamination, recycling vs reclamation, destruction and record keeping

10%

Environmental Impact (GWP/ODP)

Global Warming Potential, Ozone Depletion Potential, the Montreal Protocol and Kigali Amendment, TEWI, low-GWP and natural refrigerants and efficiency

Safety & Legislation

Safe isolation, PPE and cold-burn hazards, oxygen-free nitrogen, asphyxiation risk, HASAWA 1974, COSHH, BS EN 378 and refrigerant flammability

How to Pass the C&G 2079-11 F-Gas Category I Exam

What You Need to Know

Passing score: 60% (24 of 40)
Assessment: 40 on-screen (GOLA) multiple-choice questions over 80 minutes plus a practical assessment, graded Pass/Fail; 60% (24/40) is required on the theory paper. This practice bank is 100 selected-response items.
Time limit: 80 minutes (multiple-choice paper)
Exam fee: Typically £300-£600 for the course, exam and certification (varies by centre)

Keys to Passing

Complete 500+ practice questions
Score 80%+ consistently before scheduling
Focus on highest-weighted sections
Use our AI tutor for tough concepts

C&G 2079-11 F-Gas Category I Study Tips from Top Performers

1Be fluent with the four components and the cycle: compressor, condenser, expansion device, evaporator, and what happens to pressure, temperature and enthalpy at each stage

2Know the CO2-equivalent leak-check bands cold: 5 t = 12-monthly, 50 t = 6-monthly, 500 t = 3-monthly, with a fixed leak detector doubling each interval

3Remember CO2 equivalent = refrigerant mass (tonnes) x GWP, and that GWP measures climate impact while ODP measures ozone damage

4Distinguish recovery, recycling and reclamation, and remember that venting F-gases is illegal and detectors must sense 5 g/year

5Learn the key refrigerant facts: CFCs/HCFCs have ODP, HFCs have zero ODP but high GWP, and virgin R-404A (GWP ~3922) is service-banned above 40 t CO2e

6Complete all 100 practice questions and review every miss with the AI tutor before sitting the exam

Frequently Asked Questions

How many questions are on the C&G 2079-11 F-Gas Category I exam and how long is it?

The theory assessment is 40 on-screen multiple-choice questions to be answered within 80 minutes as a closed-book exam. You also complete a separate practical assessment. The qualification is graded Pass/Fail.

What score do I need to pass the F-Gas Category I exam?

You need 60% on the multiple-choice paper, which is 24 correct answers out of 40, and you must also pass the practical assessment. Both elements must be achieved to gain the Category I certificate.

What does F-Gas Category I (2079-11) allow me to do?

Category I is the most comprehensive tier. It legally permits leak checking, refrigerant recovery, installation, servicing and maintenance on stationary refrigeration, air-conditioning and heat-pump systems of any refrigerant charge size.

What topics does the F-Gas Category I exam cover?

It covers the refrigeration cycle and p-h diagrams, refrigerants and the retained EU F-Gas/ODS Regulations, system components, leak detection and repair, recovery/recycling/reclamation, environmental impact (GWP and ODP) and safety legislation.

Do I need prior qualifications to take C&G 2079 Category I?

It is recommended that you hold or are working towards a Level 2 NVQ in Refrigeration & Air Conditioning, or can demonstrate equivalent knowledge and practical experience. Many candidates take an assessed 3-5 day course at an approved centre.

Is this free F-Gas Category I practice as good as paid prep?

Our 100 practice questions cover the same content as the official 2079 syllabus, with a teaching explanation for every answer plus free daily AI tutor interactions. All content is free forever and updated for 2026.

100+ Free C&G 2079-11 F-Gas Category I Practice Questions

Explore More City & Guilds UK Trade Qualifications

City & Guilds 2365 Level 2 Diploma in Electrical Installations

City & Guilds 2365 Level 3 Diploma in Electrical Installations

City & Guilds 2382-22 18th Edition Wiring Regulations (BS 7671)

City & Guilds 2391-50 Initial Verification of Electrical Installations

City & Guilds 2391-51 Periodic Inspection & Testing of Electrical Installations

City & Guilds 2391-52 Combined Inspection & Testing of Electrical Installations