Question 127Refrigeration & AC - Assistant Engineer

The correct answer is B. The machine has a suspected leak because the pressure is only 10 psig, which is lower than the typical operating pressure for an R-134a chiller. To properly check for leaks, the refrigerant pressure should be raised to 35 psig by adding refrigerant, as stated in answer choice B. This is in accordance with the leak test procedures decision tree, which indicates that if the system pressure is below the normal operating range, refrigerant should be added to bring the pressure up to the normal range before performing the leak test. The other answer choices are incorrect because adding nitrogen (choice A) is not the appropriate method, the machine does not definitely not have a leak (choice C), and checking for leaks without adjusting the pressure (choice D) would not provide an accurate assessment of the system's leak status.