Question 112Refrigeration & AC - QMED

The correct answer is C) a restricted liquid line strainer. A restricted liquid line strainer can cause the running suction pressure at the refrigeration compressor to be below normal in a TXV controlled air-cooled refrigeration system. This is because a restricted strainer will limit the flow of liquid refrigerant to the expansion valve, reducing the amount of refrigerant entering the evaporator. This results in lower suction pressure at the compressor. The other options are incorrect because: A) a dirty condenser would cause the head pressure to be high, not low suction pressure; B) overfeeding by the expansion valve would result in high suction pressure; and D) a refrigerant overcharge would also cause high head pressure, not low suction pressure.