Question 22Refrigeration/AC - 1st Asst/Chief70% to pass
Which of the conditions listed could cause excessively low refrigerant pressure at the compressor suction of a TXV controlled refrigeration system?
AI Explanation
The correct answer is B) The system is low on refrigerant.
In a TXV controlled refrigeration system, a low refrigerant charge will cause excessively low pressure at the compressor suction. This is because the TXV regulates the flow of refrigerant into the evaporator based on the superheat at the evaporator outlet. With a low refrigerant charge, there is insufficient refrigerant in the system to maintain the proper pressure and temperature relationships, leading to low suction pressure at the compressor.
The other options are incorrect because:
A) The high pressure cutout would not affect the low suction pressure.
C) The box solenoid valve being stuck open would not cause low suction pressure.
D) Insufficient condenser cooling water would cause high, not low, suction pressure.
Related Questions
#20 When the relief valve opens on a refrigeration compressor discharge line, it discharges high-pressure refrigerant vapor to what location? #21 During the initial cooling down of a box temperature in a refrigeration system, which of the devices listed is used to prevent excessive gas pressure at the compressor suction for the purpose of prevention of overloading of the compressor driver? #23 An excessive charge of refrigerant in a thermostatically controlled, air-cooled, refrigeration system using a TXV as an expansion device can cause which of the following? #24 Low compressor head pressure in a refrigeration system can be caused by which of the following? #25 A reciprocating refrigeration compressor may be tested for leaking discharge valves by stopping the compressor, turning the discharge service valve all the way in, and then turning the compressor over by hand. If the discharge valves are leaking, the compound gage will show pressures which react in which way?