单项选择题 A thermostatic expansion valve is properly controlling evaporator superheatAdjusting this valve to lower the superheat will result in a/an （）.

单项选择题 It is possible to mount a double suction centrifugal pump impeller with the vanes facing in the wrong directionThis would cause the pump （）.

单项选择题 Water allowed to accumulate in the hydraulic system oil will cause an oxidation process producing by- products which are normally （）.