Question 128Refrigeration & AC - Assistant Engineer

The correct answer is B) lack of refrigerant. A refrigeration unit will short cycle (cycle on and off frequently) when there is a lack of refrigerant in the system. This is because insufficient refrigerant leads to improper cooling, causing the compressor to constantly turn on and off in an attempt to maintain the desired temperature. The other answer choices are incorrect because starting conditions (A), hot gas defrost (C), and heavy loads (D) do not directly cause short cycling on their own. Short cycling is primarily a symptom of low refrigerant levels in the system.