CARO Study Guide 2026
Everything you need to pass the CARO 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.
📋 CARO Exam Format at a Glance
📚 CARO Topics to Study (21)
✍️ Sample CARO Questions & Answers
1. Why is it important to pitch refrigerant suction lines toward the compressor?
Suction lines are pitched toward the compressor so that oil and any liquid refrigerant flow back naturally, preventing oil logging in the evaporator and liquid slugging in the compressor.
2. A low-pressure controller on an ammonia system is set to cut out at a specific suction pressure. What does a cut-in pressure setting represent?
The cut-in pressure is the suction pressure at which the low-pressure controller closes and allows the compressor to restart after conditions have returned to acceptable levels.
3. Why is preventive maintenance critical in refrigeration systems?
Preventive maintenance is critical in refrigeration systems because it helps identify and address minor issues before they escalate into major failures. Regular inspections, cleaning, and adjustments reduce wear and tear, optimize system performance, and significantly extend the operational lifespan of expensive refrigeration equipment. This proactive approach ultimately saves on costly repairs and replacements.
4. A refrigeration system has high suction pressure and high discharge pressure. What is the most likely cause?
A dirty condenser restricts heat rejection, causing both condensing pressure (discharge) and suction pressure to rise as the system struggles to remove heat from the refrigerant.
5. What PPE is most essential when handling refrigerants?
When handling refrigerants, gloves and safety goggles are essential PPE because refrigerants can cause severe frostbite if they come into contact with skin or eyes due to their extremely low temperatures. Some refrigerants can also cause chemical burns or irritation. This PPE provides critical protection against direct exposure and potential splashes.
6. A pilot-operated pressure regulating valve (PRV) in refrigeration is used to:
A pilot-operated pressure regulating valve uses a small pilot valve to sense downstream pressure and modulate the main valve to maintain a constant set pressure, enabling precise automatic pressure control.