CRST Study Guide 2026
Everything you need to pass the CRST exam in one place: the exam format, every topic to study, real practice questions with explanations, flashcards, and full-length practice tests. Free, no sign-up needed.
📋 CRST Exam Format at a Glance
📚 CRST Topics to Study (37)
✍️ Sample CRST Questions & Answers
1. A refrigeration system uses a flooded evaporator. What distinguishes it from a dry-expansion evaporator?
In a flooded evaporator, the entire heat exchanger is filled with liquid refrigerant, maximizing heat transfer surface contact.
2. What refrigerant is classified as R-717 and widely used in large industrial refrigeration systems?
R-717 is ammonia (NH3), a natural refrigerant with excellent thermodynamic properties and zero ODP/GWP widely used in industrial cold storage and food processing.
3. What type of oil is required in systems using R-410A refrigerant?
R-410A and other HFC refrigerants require POE oil because it is miscible with HFCs, ensuring adequate lubrication and oil return throughout the system.
4. What is a common cause of refrigeration system failure?
Refrigerant leaks are a very common and critical cause of refrigeration system failure. A loss of refrigerant reduces the system's cooling capacity, increases energy consumption, and can eventually lead to compressor damage due to overheating. Detecting and repairing leaks promptly is vital for system longevity, efficiency, and environmental protection.
5. What is the correct procedure before working on energized refrigeration electrical panels according to NFPA 70E?
NFPA 70E requires an arc flash risk assessment and appropriate arc-rated PPE before working on or near energized electrical equipment.
6. When brazing copper-to-copper refrigeration joints, which brazing alloy family is self-fluxing and most commonly used in the industry?
BCuP (silver-phosphorus-copper) alloys are self-fluxing on copper-to-copper joints because phosphorus acts as its own flux, making them the industry standard for refrigeration brazing.
🎯 Free CRST Practice Tests
📖 CRST Guides & Articles
What Practice Test Geeks adds beyond an AI chat for CRST
An AI chatbot can quiz you, but it can't reproduce the exam conditions or keep your record. Here you get:
- A timed, full-length CRST mock exam — 100 questions in 120 minutes with a 70% pass mark, modeled on the official exam's question count and time limit, followed by a score report broken down by exam domain.
- A fixed CRST question bank: the same test every attempt, so your score is comparable from one try to the next instead of changing with every regenerated quiz.
- Progress saved on your device: completed tests, scores and missed questions stay in My Progress, so you can retake only what you got wrong.
- A printable CRST cheat sheet you can print or save as a PDF.
- CRST flashcards built from the same question bank.
- Free CRST practice tests with the correct answer shown after each question.