单项选择题
A.compressor B.condenser C.receiver D.evaporator
The FIRST thing to do to ensure that a refrigeration un...
单项选择题The FIRST thing to do to ensure that a refrigeration unit will not start while undergoing repairs, is to （）.
A.secure and tag the electrical circuit B.place a crow bar in the flywheel of the unit C.inform all persons in the area not to start the unit D.make a log book entry
One of the main differences between the various types o...
单项选择题One of the main differences between the various types of screw pumps is in the （）.
A.stuffing box diameter B.direction of rotation of the screws C.pitch of the screws D.type of driving gears
The temperature at which water vapor in the atmosphere ...
单项选择题The temperature at which water vapor in the atmosphere begins to condense is called the （）.
A.dew point temperature B.condensation temperature C.psychometric temperature D.absolute humidity temperature
