A.the compressor short cycling on high pressure cut out switch
B.high suction pressure
C.high head pressure
D.bubbles in the sight glass
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A.The two objects must be in physical contact
B.The two objects must be the same size
C.There must be an existing temperature differential
D.There must be an existing weight differential
A.insufficient lubrication
B.insufficient refrigerant
C.excess refrigerant
D.excessive opening of the expansion valve
A.increase compressor discharge pressure on demand
B.increase compressor operating speed as necessary
C.allow the motor to turn the compressor opposed only by friction
D.reduce the compressor frictional load when starting
A.Radiation
B.Conduction
C.Convection
D.Each of the above
A.Shortage of refrigerant oil
B.Slight shortage of refrigerant
C.Excessive condenser cooling water flow
D.Faulty expansion valve
A.vary their speed according to temperature and load
B.start and come up to speed before air compression begins
C.change speed according to overload demands
D.reduce compressed air charge density
A.radiation
B.conduction
C.convection
D.condo-radiation
A.used in either the fully dosed or fully opened position
B.installed with the stem down
C.used for steam service only
D.used to throttle or regulate the flow of liquid
A.Radiation
B.Conduction
C.Natural convection
D.All of the above
A.A gate valve
B.A globe valve
C.Any check valve
D.Any needle valve
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