Question 162Refrigeration & AC - Assistant Engineer

The correct answer is A) low-pressure in the evaporator at low load. Surging in a centrifugal air conditioning compressor is caused by low-pressure in the evaporator at low load conditions. When the compressor is operating at low load, the pressure in the evaporator drops, which can cause the airflow through the compressor to become unstable and lead to surging. This unstable airflow can damage the compressor. The other options are incorrect because low-pressure in the condenser does not directly cause surging in the compressor, and low-pressure in the evaporator at high load would not lead to surging.