Question 85Refrigeration & AC - 1st Asst/Chief

The correct answer is D) 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 reduce the flow of liquid refrigerant to the expansion valve, causing it to not open fully. This reduction in refrigerant flow will result in lower suction pressure at the compressor. The other options are incorrect because: A) overfeeding by the expansion valve would cause higher suction pressure, not lower; B) a dirty condenser would cause higher head pressure, not lower suction pressure; and C) a refrigerant overcharge would cause higher head pressure and suction pressure, not lower suction pressure.