100+ Free ITI/NCVT RAC Mechanic (AITT Theory) Practice Questions

Pass your DGT/NCVT Craftsmen Training Scheme — Refrigeration and Air Conditioning Technician (Job role: Mechanic Refrigeration and Air Conditioner, NCO 7127.0100) All India Trade Test Trade Theory 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 ITI/NCVT Trade AITT Theory (India)

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

ITI Solar Technician (Electrical) Trade Theory (NCVT/NSQF, India)

Practice Questions100 questions

ITI Technician Mechatronics Trade Theory (NCVT/NSQF, India)

Practice Questions100 questions

Sample ITI/NCVT RAC Mechanic (AITT Theory) Practice Questions

Try these sample questions to test your ITI/NCVT RAC Mechanic (AITT Theory) exam readiness. Each question includes a detailed explanation. Start the interactive quiz above for the full 100+ question experience with AI tutoring.

1Before opening a refrigeration system that may contain refrigerant, which PPE practice best matches CTS RAC workshop safety?

A.Use only cotton gloves soaked in compressor oil for grip

B.Wear safety goggles/face protection and gloves suited to refrigerant and oil contact

C.Remove eye protection because fogging makes gauge reading impossible

D.Work bare-handed so you can feel pipe temperature more accurately

Explanation: CTS RAC theory emphasises trade-related hazards and PPE for refrigerant handling, pressure work and chemical contact. Eye/face protection and suitable gloves reduce injury from spray, oil and cold burns.

2During oxy-acetylene brazing of copper refrigeration tubing, which safety practice is correct?

A.Purge the work area with refrigerant vapour to displace oxygen

B.Keep cylinders upright and secured, use flashback arrestors, and clear flammables from the work area

C.Braze with oil-soaked rags wrapped around nearby joints for cooling

D.Lay acetylene cylinders on their side to improve hose reach

Explanation: Gas welding/brazing safety in the CTS syllabus requires upright secured cylinders, proper flashback protection and a clear work area. Acetylene cylinders must not be used lying down; oil-soaked rags and refrigerant purging create fire and toxicity hazards.

3When testing live electrical circuits on a window air conditioner, which practice is safest?

A.Bridge the fuse with thick copper wire so the circuit cannot trip during diagnosis

B.Touch both line and neutral with wet fingers to feel if voltage is present

C.Stand on a wet floor to improve body earthing for better meter readings

D.Use insulated tools, verify meter category rating, and de-energise before opening live terminals when possible

Explanation: CTS electrical safety outcomes require safe measurement practice, proper tools and isolation when opening terminals. Bridging fuses, wet floors and body contact with live conductors are classic shock and fire risks.

4A trainee suddenly feels dizziness after a large refrigerant leak in a poorly ventilated plant room. What is the first priority action?

A.Move the person to fresh air, stop work, ventilate the area and seek medical help if symptoms persist

B.Instruct the trainee to re-enter and tighten joints while still dizzy

C.Pour water on the person to dissolve refrigerant from the skin

D.Immediately light a match to check whether the refrigerant is flammable

Explanation: Many refrigerants displace oxygen or cause narcotic effects in high concentrations. First response is remove the person to fresh air, ventilate and get help. Ignition tests, water dousing for inhalation exposure, or continuing work while impaired are unsafe.

5How should full refrigerant cylinders be stored in an ITI RAC workshop?

A.With valves fully open to equalise room pressure

B.Stacked loosely on wooden shelves near oxy-acetylene sets

C.Upright, secured against falling, away from heat sources, with valves protected and caps fitted when not in use

D.Horizontal in direct sunlight so pressure rises for faster charging

Explanation: CTS refrigerant-handling outcomes require upright secured storage, valve protection and separation from heat/ignition. Sun heating, open valves and loose stacking near welding gases create rupture and accident risks.

6What is the purpose of flaring the end of soft copper refrigeration tubing?

A.To reduce tube wall thickness so refrigerant flows faster

B.To harden the tube permanently so it never needs insulation

C.To form a conical seat so a flare nut and fitting can make a mechanical leak-tight joint

D.To convert soft copper into steel for higher pressure rating

Explanation: Flaring creates a cone that seats against a flare fitting under the flare nut, forming a serviceable mechanical joint used widely in RAC work. It does not harden copper into steel or replace insulation.

7Compared with a flare joint, when is copper-tube swaging typically used in RAC practice?

A.To enlarge one tube end so another tube of the same size can be inserted for a brazed socket joint

B.To crimp aluminium fins onto a steel condenser only

C.To thread the tube for a pipe wrench connection

D.To flatten the tube completely as a permanent shut-off

Explanation: Swaging expands one tube end to receive another tube of equal OD for brazing. It is a common copper joining technique in the CTS RAC tools module, not a threading or shut-off method.

8Why is dry nitrogen often purged through copper tubing while brazing a refrigeration circuit?

A.To increase system refrigerant charge during brazing

B.To freeze the joint so filler metal solidifies faster

C.To displace oxygen inside the tube and reduce internal oxide scale that can clog capillaries and damage compressors

D.To chemically convert copper into brass

Explanation: Internal oxidation during open-flame brazing creates scale that travels to expansion devices and compressors. A low-pressure dry nitrogen purge displaces oxygen and limits scale.

9After sawing a mild-steel plate for a RAC equipment bracket, which finishing step best matches basic fitting practice?

A.File the cut edges square and remove burrs before drilling or assembly

B.Oil the cut heavily and skip deburring

C.Leave sharp burrs so paint adheres better

D.Hammer the edge until it curls under without filing

Explanation: CTS fitting outcomes include sawing, filing flat/square and removing burrs for safe, accurate assembly. Burrs injure hands and prevent proper mating of parts.

10Which sequence best describes making a simple sheet-metal duct collar in CTS sheet-metal practice?

A.Drill holes randomly then bend without marking

B.Only paint the sheet; cutting is never required

C.Weld first, then mark dimensions on the finished weld

D.Mark out, cut, bend/form, then join by riveting or soldering as specified

Explanation: Sheet-metal learning outcomes cover marking, cutting, bending, riveting and soldering in a planned sequence. Marking after welding or skipping layout produces inaccurate work.

About the ITI/NCVT RAC Mechanic (AITT Theory) Exam

The CTS Refrigeration and Air Conditioning Technician trade (often still searched as ITI Mechanic Refrigeration & Air-Conditioning) trains candidates to install, service, leak-test, evacuate, charge and troubleshoot domestic refrigerators, window/split/inverter and car AC, commercial cabinets, ice plants, cold storage and basic central/VRF HVAC. Professional knowledge spans safety, fitting/tubing/brazing, electrics and starters, vapour-compression theory, refrigerants/recovery, compressors, heat exchangers/expansion devices and air-side psychrometry. Successful trainees earn the National Trade Certificate (NTC) after AITT.

Assessment

Two-year CTS trade (2400 hours + 300 hours OJT/group project), NSQF Level 4, trade code DGT/1010. Summative AITT includes Trade Practical plus Computer-Based Test. Engineering-trade CBT: 75 questions / 150 marks / 2 hours covering Trade Theory (with Workshop Science & Calculation and Engineering Drawing items) and Employability Skills. Formative assessment and attendance gates apply for hall tickets per session guidelines.

Time Limit

2 hours for CBT (AITT July 2026 DGT guidelines). Practical duration follows the DGT/State Directorate schedule for the sitting.

Passing Score

33% minimum in Trade Theory and in Employability Skills; 60% minimum in Trade Practical and Formative Assessment (DGT CTS pass regulation / AITT July 2026 guidelines). No grace marks.

Exam Fee

CBT fee ₹213 per trainee for AITT July 2026 mains (plus applicable payment-gateway charges). Practical and other institute fees are notified separately on SIDH — confirm with your ITI. (Directorate General of Training (DGT), Ministry of Skill Development and Entrepreneurship)

ITI/NCVT RAC Mechanic (AITT Theory) Exam Content Outline

Workshop Safety & PPE

Trade hazards, PPE, electrical and brazing safety, refrigerant-leak response and cylinder storage (ELE/N1002).

Fitting, Sheet Metal & Copper Tubing

Marking/filing/drilling, sheet-metal joints, tube cutting, flaring, swaging, brazing with nitrogen purge and thermal insulation.

10%

Electricity, Electronics & Starters

Ohm’s law, earthing, multimeters, diodes/resistors, capacitors/relays, DOL and star-delta starting, inverter drive basics.

12%

Refrigeration Fundamentals & Cycle

Vapour-compression components, latent heat, P-T relations, superheat/subcooling, COP and ton of refrigeration.

Refrigerants, Recovery & Retrofit

CFC/HFC/ozone and GWP issues, recovery (no venting), leak test, evacuation, filter-driers, weighing charge and compatibility.

12%

Compressors & Motors

Hermetic terminals C/S/R, oil, commercial reciprocating service, HP cut-outs, DOR, burnout flush and selection.

10%

Condensers, Evaporators & Expansion

Air/water-cooled condensers, cooling towers, capillaries/TXVs, frost, receivers and chiller evaporators.

Domestic Refrigerators

Direct-cool vs frost-free, thermostats, gaskets, inverter fridges, airflow, capillary/drier service and door-switch faults.

14%

Window, Split, Inverter & Car AC

Window install, split line sets, multi/cassette/ducted types, inverter part-load control, drains, car clutch and performance checks.

Commercial Refrigeration

Water coolers, deep freezers, ice plants, bottle/visible coolers, walk-in/cold storage maintenance and pump-down.

HVAC Psychrometry, Central & VRF

DBT/WBT/RH, ducts, AHU/dampers, package AC, central plant concepts and VRF/VRV identification.

How to Pass the ITI/NCVT RAC Mechanic (AITT Theory) Exam

What You Need to Know

Passing score: 33% minimum in Trade Theory and in Employability Skills; 60% minimum in Trade Practical and Formative Assessment (DGT CTS pass regulation / AITT July 2026 guidelines). No grace marks.
Assessment: Two-year CTS trade (2400 hours + 300 hours OJT/group project), NSQF Level 4, trade code DGT/1010. Summative AITT includes Trade Practical plus Computer-Based Test. Engineering-trade CBT: 75 questions / 150 marks / 2 hours covering Trade Theory (with Workshop Science & Calculation and Engineering Drawing items) and Employability Skills. Formative assessment and attendance gates apply for hall tickets per session guidelines.
Time limit: 2 hours for CBT (AITT July 2026 DGT guidelines). Practical duration follows the DGT/State Directorate schedule for the sitting.
Exam fee: CBT fee ₹213 per trainee for AITT July 2026 mains (plus applicable payment-gateway charges). Practical and other institute fees are notified separately on SIDH — confirm with your ITI.

Keys to Passing

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

ITI/NCVT RAC Mechanic (AITT Theory) Study Tips from Top Performers

1Weight revision to high Professional Knowledge hours: split/window AC service, compressors/motors, vapour-compression diagnostics (superheat/subcooling), and refrigerant recovery/retrofit—not only component name recall.

2Pair each theory topic with workshop practice: flare/swage/braze joints, nitrogen leak tests, deep vacuum before weigh-in charging, multimeter winding checks and condenser cleaning.

3For commercial and HVAC modules, prioritise safety, airflow/psychrometry basics, AHU/damper purpose and VRF identification over memorising unverifiable numeric setpoints not published in the CTS PDF.

Frequently Asked Questions

Is ITI Mechanic (Refrigeration & Air-Conditioning) the same as Refrigeration and Air Conditioning Technician?

Yes for current CTS naming: DGT’s curriculum title is Refrigeration and Air Conditioning Technician (trade code DGT/1010; NCO 7127.0100 Mechanic Refrigeration and Air Conditioner). Older materials and search queries often still say Mechanic (RAC); practice content follows the current CTS learning outcomes.

How many questions are on the AITT CBT for this engineering trade?

Per DGT AITT July 2026 guidelines, the CBT is 75 multiple-choice questions for 150 marks in two hours: 50 questions (100 marks) in the Trade Theory block (38 trade theory + 6 WSC + 6 engineering drawing) and 25 Employability Skills questions (50 marks). This practice bank provides 100 trade-theory-focused MCQs for revision.

What is the pass mark for AITT Trade Theory?

DGT requires at least 33% in Trade Theory and 33% in Employability Skills, and at least 60% in Trade Practical and Formative Assessment. There are no grace marks. Confirm any session-specific notifications on the DGT exam corner or SIDH.

What is the CBT examination fee?

For AITT July 2026 mains, DGT notified a CBT fee of ₹213 per trainee (plus payment-gateway charges), payable online via SIDH. Practical fees are separate — ask your ITI for the exact amount for your sitting.