South Carolina - Refrigeration Practice Exam
Free Practice Exam
Test your knowledge with 10 questions from our pool of 20 free questions.
- 10 questions per attempt
- 30 minute time limit
- Unlimited attempts
- A new mix each time
- Instant results
Full Practice Exam
Complete exam simulation matching the real PSI test format.
- 50 questions (same as real exam)
- 180 minute time limit
- 7 topic areas covered
- 284 questions in pool
- Detailed explanations
Texts preferred · 9am–9pm Central
South Carolina - Refrigeration Practice Exam Guide
What's on the exam
Questions per topic, out of 50This practice exam follows the official content outline for the South Carolina - Refrigeration exam: Code Compliance, HARV General, HARV Maintenance, HARV Controls, Piping - General, Piping - Dimensioning and Design, Safety.
You have two ways to practice. The free practice exam gives you 10 questions per attempt, and you can retake it as often as you like. The full practice exam gives you 50 questions on a 3 hours clock, with a new draw from our question bank every attempt.
Code Compliance 7 items
Our study plan for this topic: Permit requirements, application procedures, and fees; Inspections and testing requirements for mechanical systems; Authority and duties of the code official; Refrigerant classification, allowable quantities, and occupancy restrictions; Machinery room construction and ventilation requirements; Refrigerant piping materials, joints, and installation standards; Equipment listing, labeling, and approval requirements; OSHA general safety and health provisions for construction contractors.
HARV General 11 items
Our study plan for this topic: Compression refrigeration cycle components and operation; Refrigerant classification, properties, and environmental impact (ODP, GWP, Clean Air Act); Refrigerant handling equipment: cylinders, gauge manifolds, service valves, and pressure gauges; Refrigerant recovery, recycling, reclaiming, and evacuation procedures; Leak detection methods and refrigerant charge verification (superheat and subcooling); Metering devices: capillary tubes, TXVs, AXVs, EEVs, and fixed-orifice types; Heat exchangers: evaporator and condenser types, construction, and defrost methods; Refrigerant flow components: filter-driers, sight glasses, liquid receivers, check valves, and solenoid valves.
HARV Maintenance 8 items
Our study plan for this topic: Refrigerant charge verification using subcooling and superheat methods; Refrigerant recovery procedures (passive and active methods); System evacuation and leak detection techniques; Compressor inspection and testing (hermetic and open-drive); Filter-drier and sight glass inspection and replacement; Electrical component testing using voltmeters, ammeters, and ohmmeters; Condenser and evaporator cleaning and maintenance; Motor lubrication, belt tension, and bearing inspection.
HARV Controls 8 items
Our study plan for this topic: Thermostat sensing elements and switching devices (bimetal strips, thermistors, mercury switches, reed switches); Heat and cooling anticipators (operation, adjustment, and effect on system overshoot and lag); Thermostat types by voltage class (line-voltage, low-voltage 24 Vac, millivolt); Thermostat terminal identification and wiring conventions (R, W, Y, G, C, O/B terminals); Programmable and digital thermostat features (scheduling, override, wireless/Wi-Fi, power-stealing); Zoned system controls (zone control panels, damper types, bypass dampers, master-slave thermostats); Thermostat diagnostics and troubleshooting procedures (voltage measurements, jumper tests, multistage systems); Control system range and differential adjustment (cut-in, cut-out, set point effects on run time and cycle interval).
Piping - General 3 items
Our study plan for this topic: Types of refrigerant tubing and pipe (ACR copper, stainless steel, aluminum); Non-refrigerant piping materials (copper water tubing, plastic pipe, steel pipe); Tubing cutting, reaming, and bending procedures; Flared, soldered, brazed, and swaged tubing connections; Pipe joining methods (threaded, solvent-cemented, welded, mechanical joints); Hydronic piping materials standards and fitting requirements; Fuel oil piping materials, joints, and installation requirements; Pipe support spacing and hanger requirements.
Piping - Dimensioning and Design 9 items
Our study plan for this topic: Pipe and tubing dimensions by material type (copper ACR, Type K/L/M, steel schedules, plastic); Setback and length of bend calculations for standard angles (15° through 180°); Offset bend calculations (travel, run, and offset relationships); Fitting laying lengths and center-to-end dimensions for elbows, tees, and reducers; Pipe support spacing requirements based on pipe material, size, and temperature; Hydronic piping material standards and approved joint types per SC Mechanical Code; Pipe expansion allowances and thermal compensation methods; Minimum bending radius requirements for tubing and pipe.
Safety 4 items
Our study plan for this topic: Lockout/tagout (LOTO) procedures for electrical and mechanical systems; Personal protective equipment (PPE) selection and requirements; Refrigerant, chemical, and breathing hazards identification; Fire hazards, fire extinguisher classes, and fire prevention; Fall protection systems and requirements (guardrails, safety nets, personal fall arrest); Confined space entry requirements and permit procedures; SC 811 excavation notification requirements, locate requests, and excavator responsibilities; Hazard communication, safety data sheets (SDS), and toxic/hazardous substance exposure limits.
Sample 1 — HARV General
Question: You are selecting a thermostatic expansion valve for a commercial evaporator coil. Your measurements show a measurable pressure drop between the evaporator inlet and the evaporator outlet, and you must decide whether an internally equalized valve will provide accurate superheat control. An externally equalized valve should be used when the pressure drop through the evaporator exceeds what value?
- A. 12 psi
- B. 8 psi
- C. 4 psi
- D. 20 psi
Correct Answer: C
Modern Refrigeration and Air Conditioning (22nd ed.), Section 45.1.2 (Page 1083), states that an equalizer should be used if the pressure drop between the inlet of the evaporator and the outlet is more than 4 psi (28 kPa). The external equalizer delivers suction-line pressure at the sensing bulb location to the underside of the diaphragm, compensating for evaporator pressure drop so superheat can be adjusted accurately. Internally equalized valves sense evaporator inlet pressure and do not provide accurate control with large pressure drops; uncompensated pressure drop increases the superheat effect and leads to a starved evaporator. The 20 psi figure is the approximate opening differential of a receiver pressure regulator (ORD valve), not an equalizer criterion.
Reference: Modern Refrigeration and Air Conditioning (22nd ed.), Page 1083
Sample 2 — Piping - Dimensioning and Design
Question: In a lift check valve, the disc is designed to move in which direction when the valve opens and closes?
- A. Pivoting on a hinge pin in an arc
- B. Rotating around a central spindle axis
- C. Vertical, rising and falling freely
- D. Horizontal, sliding across the seat
Correct Answer: C
The working parts of lift check valves consist of a valve disc positioned so that it is free to rise and fall in a vertical direction. Pressure from the flowing liquid raises the disc, and when flow stops, the disc drops back to a closed position by gravity.
Reference: Pipefitter's Handbook (3rd ed.), Chapter 1 (Full Text), Check Valves — Description
Sample 3 — HARV Maintenance
Question: You are troubleshooting a large commercial compressor that uses a pressure lubrication system. Compared to a splash lubrication system, what is an operational advantage of the pressure system?
- A. It eliminates the need for any oil in the crankcase
- B. It requires fewer moving parts and lower maintenance costs
- C. It allows greater bearing clearances while running quieter
- D. It does not require oil passages drilled in the crankshaft
Correct Answer: C
A pressure lubrication system delivers oil under pressure to all bearing surfaces, providing better protection than a splash system. A compressor with pressure lubrication will run quieter even though it has greater bearing clearances, because the pressurized oil cushions the bearing surfaces.
Reference: Modern Refrigeration and Air Conditioning (20th ed.), Chapter 18, Section 18.3.4 — Pressure Lubrication
Treat your first attempt as a checkup, not a verdict. After every attempt, the results page breaks your score down by outline topic, so you can see which topics need work. Compare your score with the real exam's passing score, 35 correct answers out of 50 scored questions, and keep practicing until you pass consistently.
- Answer what you know first. Go through every question once, answer the ones you know, and bookmark the rest. Our practice exams let you bookmark and come back.
- Come back to your bookmarks. Work them out on your second pass.
- Watch your pace. The real exam works out to about 3 minutes 36 seconds per question.
- Look up every miss. After each attempt, find each missed question's reference in your book and read the section.
| Questions | 50 questions |
| Time limit | 3 hours |
| Passing score | 35 correct answers out of 50 scored questions |
| Books in the exam room | Open book |
| Exam fee | $78 |
- Your score is given immediately after the examination on screen and on a printed official report, with a diagnostic report of strengths and weaknesses if you do not pass.
- Except for Burglar and Fire Alarm, an examination may be taken only 2 times in a 12-month period and thereafter only once in six months, and a candidate who passes an exam may not take it again.
Source: Commercial Contractor Candidate Information Bulletin, Updated 8/27/2026. Check the bulletin before test day: fees and rules can change.