海船船员考试
单选题If the head pressure is too high,（）A the relief valve should open before the high-pressure cutoutB the relief valve should open and let excess refrigerant go to receiverC the high-pressure cutout switch should operate before the relief valve opensD clo
题目
the relief valve should open before the high-pressure cutout
the relief valve should open and let excess refrigerant go to receiver
the high-pressure cutout switch should operate before the relief valve opens
close in on the suction valve
相似问题和答案
第1题：
If fuel injection to a four-stroke/cycle diesel engine begins earlier than designed, ignition may be delayed because the
A.cylinder compression pressure may not be high enough
B.cylinder compression temperature may be too high
C.fuel oil injection pressure may not be high enough
D.scavenge and purge process is incomplete
第2题：
If the head pressure of a reciprocating refrigeration compressor is excessive
A.the relief valve should open before the high pressure cutout
B.the relief valve should open and allow the excess refrigerant to flow to the receiver
C.the high pressure cutout switch should operate before the relief valve opens
D.you should close the discharging valve
第3题：
It can be inferred that the high rate of dropouts lies in_________
A． the too low salary for PhD
B． the too rigid academic requirement
C． the too high salary for dropouts
D． 1000 positions
可由倒数第二段This may also be an indication of the fact that top salaries in the academic fields．where the PhD’s tend to rise to the highest salaries，are still lagging behind other fields．推出A项正确。B项“学术要求太严”只是某些人辍学的原因。C项错误，因为辍学者有一部分人工资高于博士生。D项文中没有提到。
第4题：
A barometer showing falling pressure indicates the approach of a ______.
A.high pressure system
B.low pressure system
C.high dew point
D.low dew point
气压计显示气压下降，表示低气压临近。
第5题：
In the refrigeration system, a shortage of refrigerant is indicated by
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
第6题：
If a refrigeration compressor is short cycling on high head pressure, you should
A.purge the condenser if the waterside is dirty
B.check for proper water flow through the condenser
C.increase the high pressure cutout setting
D.reduce the cooling water flow
第7题：
When adding oil to a refrigeration system, precautions must be taken to ensure that
A.the compressor suction pressure is not too high
B.all air is purged from the pump and charging fittings
C.the high pressure cutout switch is held open to prevent accidental starting
D.the condenser is completely shutdown first
第8题：
Care must be taken not to wash or iron synthetic fibers at _____.
A、a too high temperature
B、too a high temperature
C、too high a temperature
D、a temperature too high
第9题：
The head line is too tight.
第10题：
B.attend
C.contribute
D.turn