Coast Guard Exams
Question 77Refrigeration/AC - QMED70% to pass

An increasing head pressure in a refrigeration system, without any corresponding change in the cooling water inlet temperature, would probably be caused by which of the following?

AI Explanation
The correct answer is D) air and non-condensable gases in the condenser. An increasing head pressure in a refrigeration system, without any corresponding change in the cooling water inlet temperature, is typically caused by the presence of air and non-condensable gases in the condenser. These gases reduce the condenser's ability to effectively condense the refrigerant, leading to a rise in the system's head pressure. The other answer choices are incorrect because: A) water in the refrigerant would not cause a rise in head pressure without a change in cooling water temperature, B) a restriction in the liquid line would affect the low-pressure side, not the high-pressure side, and C) flooding back of liquid refrigerant would actually decrease the head pressure.