单项选择题
A.discharge service valve as a vapor B.suction service valve as a liquid C.charging valve as a liquid D.condenser purge valve as a vapor
When adding oil to a refrigeration system, precautions ...
单项选择题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
In a refrigeration system, if the cooling water to the ...
单项选择题In a refrigeration system, if the cooling water to the condenser fails, the（）.
A.box temperature solenoid valve will close B.expansion valve will close C.compressor will shutdown D.king valve will open
Accidental flooding of the engine room bilges by the bi...
单项选择题Accidental flooding of the engine room bilges by the bilge main is prevented by （）.
A.stop-check valves installed in the bilge manifolds B.using a positive displacement reciprocating bilge pump C.installing eductors in all bilge rose boxes D.installing a swing check before each bilge valve
