单项选择题
A.Differential B.Trunk C.Barrel D.Valve-in-head
A cracked diaphragm in a thermostatic expansion valve w...
单项选择题A cracked diaphragm in a thermostatic expansion valve will cause the valve to （）.
A.return to a neutral position B.flood the evaporator C.open D.close
If an air compressor is used to supply air primarily to...
单项选择题If an air compressor is used to supply air primarily to the combustion control system and other pneumatic controllers, the entire system is known as the （）.
A.control air system B.forced draft air system C.supply air system D.ships service air system
When it is necessary to open a refrigeration system for...
单项选择题When it is necessary to open a refrigeration system for repairs and the system will be open for more than a few minutes, the open ends of the system should be （）.
A.dehydrated B.purged C.plugged D.evacuated
