Idaho Limited Electrical Refrigeration, Heating & Air Conditioning Installer Practice Exam
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Test your knowledge with 10 questions from our pool of 20 free questions.
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Full Practice Exam
Complete exam simulation matching the real PSI test format.
- 45 questions (same as real exam)
- 120 minute time limit
- 7 topic areas covered
- 253 questions in pool
- Detailed explanations
Texts preferred · 9am–9pm Central
Idaho Limited Electrical Refrigeration, Heating & Air Conditioning Installer Practice Exam Guide
What's on the exam
Questions per topic, out of 45This practice exam follows the official content outline for the Idaho Limited Electrical Refrigeration, Heating & Air Conditioning Installer exam: 2017 National Electrical Code, NFPA – Introduction, 2017 National Electrical Code, NFPA – Chapter 1, 2017 National Electrical Code, NFPA – Chapter 2, 2017 National Electrical Code, NFPA – Chapter 3, 2017 National Electrical Code, NFPA – Chapter 4, 2017 National Electrical Code, NFPA – Chapter 7, 2017 National Electrical Code, NFPA Calculations.
- Free practice exam: 10 questions per attempt, retake as often as you like.
- Full practice exam: 45 questions on a 2 hours clock, a new draw from our bank every attempt.
2017 National Electrical Code, NFPA – Introduction 2 items
Our study plan for this topic: Purpose and scope of the NEC (practical safeguarding of persons and property); NEC scope: covered and not-covered installations (90.2); Code arrangement and chapter hierarchy (90.3); Authority having jurisdiction (AHJ): enforcement powers and special permission; Mandatory vs. permissive rules and explanatory material (shall/shall not vs. shall be permitted); Equipment examination, listing, and approval for safety (90.7); Units of measurement: SI and inch-pound dual system (90.9); Wiring planning for future expansion and circuit enclosure limitations (90.8).
2017 National Electrical Code, NFPA – Chapter 1 3 items
Our study plan for this topic: Key NEC definitions and terminology (Article 100); Equipment approval, listing, and labeling requirements; Electrical connections, splices, and conductor temperature limitations; Working space and clearance requirements around electrical equipment; Guarding of live parts and arc-flash hazard warning; Equipment marking and identification of disconnecting means; Enclosure type selection for environmental conditions; Wiring integrity, conductor materials, and approved wiring methods.
2017 National Electrical Code, NFPA – Chapter 2 10 items
Our study plan for this topic: Grounding and bonding requirements for services and separately derived systems; Grounding electrode system types, installation, and sizing; Equipment grounding conductor types, sizing, and identification; Bonding of piping systems, structural metal, and service equipment; GFCI and AFCI protection requirements for branch circuits; Branch-circuit load calculations and conductor ampacity requirements; Overcurrent protection devices, ratings, and location requirements; Feeder and service load calculation methods including demand factors.
2017 National Electrical Code, NFPA – Chapter 3 6 items
Our study plan for this topic: Conductor ampacity tables and temperature correction/adjustment factors (Article 310); Conductor types, insulation designations, and permitted uses by location (Article 310); Protection of cables and raceways against physical damage through framing members and structural elements (Article 300); Underground wiring installation requirements and minimum burial depths (Article 300); Wiring in ducts, plenums, and air-handling spaces (Article 300); Box and conduit body fill calculations and minimum sizing for outlet, device, pull, and junction boxes (Article 314); Installation requirements for flexible conduit types: FMC, LFMC, and LFNC — uses, securing, and grounding (Articles 348, 350, 356); Installation requirements for rigid and nonmetallic conduit systems: RMC, EMT, and PVC — supports, bends, and grounding (Articles 344, 358, 352).
2017 National Electrical Code, NFPA – Chapter 4 16 items
Our study plan for this topic: Motor branch-circuit conductor sizing and ampacity requirements (Article 430, Part II); Motor overload protection selection and settings (Article 430, Part III); Motor branch-circuit short-circuit and ground-fault protective device ratings (Article 430, Part IV); Motor disconnecting means types, ratings, and location requirements (Article 430, Part IX); Motor controller ratings, markings, and design requirements (Article 430, Parts VII–VIII); Air-conditioning and refrigerating equipment branch-circuit conductors, disconnecting means, and overload protection (Article 440); Fixed electric space-heating equipment branch circuits, overcurrent protection, and disconnecting means (Article 424); Appliance branch-circuit ratings, overcurrent protection, and disconnecting means (Article 422).
2017 National Electrical Code, NFPA – Chapter 7 7 items
Our study plan for this topic: Class 1, Class 2, and Class 3 circuit definitions and classifications; Power source requirements for Class 1, Class 2, and Class 3 circuits; Overcurrent protection for Class 1 circuits; Wiring methods for Class 1, Class 2, and Class 3 circuits; Separation requirements between Class 2/Class 3 and power circuits; Cable types and listing requirements for Class 2, Class 3, and PLTC cables; Installation of Class 2 and Class 3 cables in specific locations (plenums, risers, ducts); Circuits and equipment operating at less than 50 volts.
2017 National Electrical Code, NFPA Calculations 1 item
Our study plan for this topic: Branch-circuit conductor sizing for motor loads (125% rule, Article 430.22); Motor branch-circuit short-circuit and ground-fault protective device ratings (Table 430.52); Motor overload protection selection and trip current percentages (Article 430.32); Hermetic refrigerant motor-compressor branch-circuit conductor ampacity (Article 440.32); Branch-circuit short-circuit and ground-fault protection for hermetic refrigerant motor-compressors (Article 440.22); Feeder and service load calculations including motor loads (Articles 220.40, 220.50); Conductors supplying multiple motors or combined motor and other loads (Articles 430.24, 440.33); Full-load current values from NEC motor tables (Tables 430.247, 430.248, 430.249, 430.250).
Sample 1 — 2017 National Electrical Code, NFPA – Chapter 4
Question: You are servicing a large stationary ac motor in a mechanical room, and the disconnecting means is a general-use isolating switch plainly marked "Do not operate under load." This type of disconnect is permitted only for stationary ac motors rated more than how many horsepower?
- A. 40 hp
- B. 20 hp
- C. 100 hp
- D. 75 hp
Correct Answer: C
NEC 430.109(E) permits a general-use or isolating switch plainly marked "Do not operate under load" to serve as the disconnecting means for stationary motors rated more than 40 hp dc or 100 hp ac. The 40 hp figure applies to dc motors only.
Reference: NEC 2017 Section 430.109(E)
Sample 2 — 2017 National Electrical Code, NFPA – Chapter 2
Question: A service call takes you to an older dwelling that still uses plug fuses. To verify that the fuses installed are rated 15 amperes or lower, you check the shape of the window, cap, or other prominent part of the fuse. Which configuration identifies a plug fuse of 15-ampere or lower rating?
- A. Octagonal configuration
- B. Hexagonal configuration
- C. Triangular configuration
- D. Square configuration
Correct Answer: B
Per NEC 2017, 240.50(C), plug fuses of 15-ampere and lower rating shall be identified by a hexagonal configuration of the window, cap, or other prominent part to distinguish them from fuses of higher ampere ratings.
Reference: NEC 2017 Section 240.50(C)
Sample 3 — 2017 National Electrical Code, NFPA – Chapter 7
Question: The input leads of a transformer supplying a Class 2 circuit are permitted to be smaller than 14 AWG, but not smaller than 18 AWG, provided the insulation is suitable and the leads do not exceed what length?
- A. 450 mm (18 in.)
- B. 250 mm (10 in.)
- C. 150 mm (6 in.)
- D. 305 mm (12 in.)
Correct Answer: D
The exception to NEC 2017, 725.127 permits input leads of a transformer or other power source supplying Class 2 and Class 3 circuits to be smaller than 14 AWG but not smaller than 18 AWG, if they are not over 305 mm (12 in.) long and have insulation complying with 725.49(B).
Reference: NEC 2017 Section 725.127 Exception
- Your results break the score down by outline topic.
- The real exam's passing score: a minimum score of 70.
- Keep practicing until you pass consistently, not just once.
- Answer what you know first and bookmark the rest. Our practice exams let you bookmark and come back.
- Work your bookmarks on the second pass.
- Real exam pace: about 2 minutes 40 seconds per question.
- After each attempt, look up every miss in your book.
| Questions | 45 questions |
| Time limit | 2 hours |
| Passing score | a minimum score of 70 |
| Books in the exam room | Open book |
| Exam fee | $75 |
- Your score is shown on screen at the end of the exam and a score report is provided, with a diagnostic report of strengths and weaknesses if you fail.
- If you do not pass, you may retake the exam as many times as needed, paying an examination fee for each attempt.
Source: Examination Scheduling Procedures / Examination Guide (Idaho PSI Candidate Bulletin), Effective 7/9/2026. Check the bulletin before test day: fees and rules can change.