單項選擇題Air entering an air-cooled refrigeration system is indicated by ().

A.frosting of the liquid line
B.higher than normal head pressure
C.a clear sight glass
D.abnormally cold reefer boxes


您可能感興趣的試卷

你可能感興趣的試題

1.單項選擇題When installing a hydraulic hose, which of the following precautions should be taken?()

A.The hose should not be twisted
B.The hose should be protected with a sleeve if it is subjected to rubbing
C.There should be some slack in the hose
D.All of the above

3.單項選擇題Which pump installation would require an external source of sealing water?()

A.Main circulator pump jacket water cooling
B.Salt water service pump
C.Auxiliary condensate pump
D.Bilge pump

4.單項選擇題The accumulation of air and other non-condensable gases in a refrigeration system will ().

A.cause a loss of the liquid seal
B.create a vapor lock in the liquid receiver
C.collect in the condenser
D.cause foaming of the oil in the crankcase

5.單項選擇題Pressure in an operating hydraulic system is developed ().

A.only by the pump as its primary function
B.by resistance to the fluid flow through the system
C.by the thermal input to the systems fluid
D.solely by the charge applied by the accumulators