单项选择题
A.a shortage of refrigerant
B.the compressor running continuously
C.liquid refrigerant returning to the compressor
D.the compressor short cycling on the high pressure cutout
单项选择题 The primary reason low pressure evaporators produce distillate more efficiently, and with less scale formation, than high pressure evaporators is （）.
单项选择题 Vessel propellers are classified as being right hand or left handA right hand propeller turns clockwise when viewed from（）.
单项选择题 Less scale formation occurs in a flash evaporator than in a submerged tube evaporator because （）.