單項(xiàng)選擇題Before charging a refrigeration unit, the refrigerant charging lines should be()

A.flushed with clean refrigerant oil
B.purged with the refrigerant
C.washed with an ammonia and alcohol solution
D.grounded to compressor


您可能感興趣的試卷

你可能感興趣的試題

1.單項(xiàng)選擇題In the presence of an open flame or hot surfaces, chlorinated fluorocarbon refrigerants decomposes and from ()

A.petroleum crystals
B.phosgene gas
C.water vapor
D.carbon monoxide

2.單項(xiàng)選擇題In an operating refrigeration system low on refrigerant, a liquid line sight glass will()

A.be clear
B.be blue
C.be light green
D.show bubbles

3.單項(xiàng)選擇題The thermal expansion valve reacts directly to the ()

A.temperature in the space being cooled
B.liquid refrigerant pressure at the solenoid valve
C.pressure drop across the evaporator coils
D.refrigerant gas superheat at the coil outlet

4.單項(xiàng)選擇題When transmitted by a reduction gear, diesel engine speed is reduced and the torque available for work ()

A.remains the same
B.is reduced
C.is increased
D.is eliminated

5.單項(xiàng)選擇題Pitting in the area close to the pitch line and on the same end of each gear tooth of a reduction gear unit would be caused by ()

A.corrosion on the gears
B.excessive gear speed
C.dirt in the oil
D.misalignment of the gears

最新試題

Which one is NOT the ‘clear grounds’ for a more detailed inspection?()

題型:?jiǎn)雾?xiàng)選擇題

When does auxiliary burner of incinerator put into operation? ()Ⅰ. start incinerator when it is coldⅡ. the sludge for dealing with is littleⅢ. the sludge for dealing with is largeⅣ. the water and impurity in sludge are too muchⅤ. the temperature in incinerator is lowⅥ. dealing with little solid rubbish

題型:?jiǎn)雾?xiàng)選擇題

By comparing the exhaust gas temperature of each cylinder, the operator can determine if the load is balanced throughout the engine. The device most commonly used is a()

題型:?jiǎn)雾?xiàng)選擇題

Refrigerant entering the compressor of a refrigeration system should be in which of the following conditions?()

題型:?jiǎn)雾?xiàng)選擇題

Thermostatic steam pressure reducing valves are used in the fuel oil service system to control the()

題型:?jiǎn)雾?xiàng)選擇題

The shipboard oil pollution emergency plan will be invalid after ()

題型:?jiǎn)雾?xiàng)選擇題

Which of the diesel engine components listed increase air density and helps to improve engine operating efficiency?()

題型:?jiǎn)雾?xiàng)選擇題

()connectors hold best if a wire is accidentally pulled or a connection becomes loose.

題型:?jiǎn)雾?xiàng)選擇題

Which of the following items don’t belong to dock repair works?()

題型:?jiǎn)雾?xiàng)選擇題

The main purpose of port State control is not to()

題型:?jiǎn)雾?xiàng)選擇題