If the thermal bulb of an expansion valve is incorrectly placed at the center of the coil instead of the end, it will （）.

If the head pressure of a reciprocating refrigeration compressor is excessive, （）.

The amount of fluid friction or internal friction inherent in a mineral lubricating oil is reflected as a measure of its （）.

The control mode in which the final control element is moved from one of two flexed positions to the other is known as （）.

A salinity indicator is used to determine the （）.

Which of the following problems could cause the high pressure cutout switch to shut down the compressor in a refrigeration system?（）

A gradual decrease in the discharge pressure of an operating hydraulic pump can be caused by （）.

The rate of heat transfer from a hot region to a cold region is affected most by the （）.

Pitting in the suction areas of a centrifugal pump bronze impeller is usually caused by （）.

One cause of high head pressure occurring in a refrigeration system can be （）.