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The principal purpose of sub-cooling liquid refrigerant prior to its entering the expansion valve is to _____.

  • A.increase the refrigerating effect, by decreasing the amount of flash gas
  • B.allow the refrigerant to enter the throttling device in a saturated condition
  • C.increase the refrigerating effect by increasing the amount of flash gas
  • D.minimize the temperature drop of the liquid as it passes through the solenoid valve to the outlet side
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