USCG Exam PracticeRefrigeration and air conditioning
A refrigeration compressor trips on the high-pressure cutout. Which of the following conditions is LEAST likely to be the cause?
- A. Fouled or scaled condenser tubes reducing heat rejection
- B. Loss of seawater cooling flow to the condenser
- C. Non-condensable air trapped in the condenser shell
- ✓ Loss of refrigerant charge causing a starved evaporatorCorrect
Why D is correct
NAVEDTRA 14075 §6-2 and §6-3 identify fouled condenser tubes, lost cooling water, and non-condensable air as causes of elevated high-side pressure that can trip the high-pressure cutout. Loss of refrigerant charge causes suction pressure to fall, which trips the low-pressure cutout, not the high-pressure cutout.