Question 192Refrigeration & AC - Assistant Engineer

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