🔍 Key Concepts
• Follow the refrigerant flow path from the compressor discharge, through the condenser/receiver, expansion devices, evaporators, and back to the compressor suction.
• Recall that refrigerant is coldest immediately after expansion and in the evaporator/suction line, and warmest at compressor discharge.
• Compare where valves 16, 18, 20, and 32 are located in relation to the evaporators (K and J) and the compressor (A).
💭 Think About
• Identify which of the numbered valves is located in, or closest to, the lowest-pressure, low‑temperature side of the system (evaporator/suction side).
• Ask yourself for each valve: Is the refrigerant here high‑pressure liquid, condensing, evaporating, or hot discharge gas? Which of those states corresponds to the lowest temperature?
• Look at how the suction lines from the evaporators join together: through which of the listed valves does that combined cold vapor pass before heading to the compressor?
✅ Before You Answer
• Verify which side of compressor A each valve (16, 18, 20, 32) is on: discharge (hot, high pressure) vs suction (cold, low pressure).
• Confirm which of the listed valves is downstream of the evaporators (J and K) and still in the low‑temperature region, before any compression or heat addition occurs.
• Make sure you are not choosing any valve that is clearly in the hot-gas discharge line or in the high‑pressure liquid line coming from the condenser/receiver.