Question 133Refrigeration & AC - Assistant Engineer

The correct answer is B) system leaks on the low side. In a low-pressure refrigeration system, excessive running of the purge recovery unit generally indicates a system leak on the low side. The purge recovery unit is designed to remove non-condensable gases, such as air, from the system. Excessive running of this unit suggests that there is a leak on the low-pressure side of the system, allowing air to be drawn into the system, which then needs to be continuously purged out. The other answer choices are incorrect because a faulty purge system vent valve (A) would not cause excessive purge unit running, a leak on the high side (C) would not significantly impact the low-side purge unit, and an overcharged system (D) would not necessarily lead to excessive purge unit operation.