Question

in its 430 Modern Refrigeration and Air Conditioning Workbook 58. A traditional mechanical refrigeration system maintains suction and head pressures during normal operation, and a compound refrigeration system maintains refrigerant circuits during normal operation. A. only one pressure value B. two pressure values C. three pressure values D. four pressure values

Answer 1

In simple refrigeration systems the compressor is controlled by simple pressure switch, with the expansion performed by a capillary tube or thermostatic expansion valve. But in compound systems in addition to operational controls separate high pressure and low pressure switches are normally used to provide secondary protection to the compressor and other components. So there are two pressure valves in compound refrigeration systems.

So the correct option is B. "Two pressure valaves"