网友您好， 请在下方输入框内输入要搜索的题目：
题目内容
（请给出正确答案）
单选题
Refrigerant entering the compressor of a refrigeration system should be in which of the following conditions?（）
A
Sub-cooled liquid
B
Sub-cooled vapor
C
Superheated vapor
D
Liquid
参考答案
参考解析
解析：
暂无解析
更多 “单选题Refrigerant entering the compressor of a refrigeration system should be in which of the following conditions?（）A Sub-cooled liquidB Sub-cooled vaporC Superheated vaporD Liquid” 相关考题
考题
Which of the conditions listed will cause a refrigeration compressor to run constantly without simultaneously decreasing the temperature in the refrigerated space?( )A.Shortage of refrigerant oilB.Slight shortage of refrigerantC.Excessive condenser cooling water flowD.Faulty expansion valve
考题
If the refrigeration compressor crankcase is sweating, the cause may be due toA.a shortage of refrigerantB.the compressor running continuouslyC.liquid refrigerant returning to the compressorD.the compressor short cycling on the high pressure cutout
考题
Low compressor head pressure in a refrigeration system can be caused by ___.A.insufficient condenser cooling waterB.excessive condenser cooling waterC.air in the refrigeration systemD.excessive refrigerant in the system
考题
In the refrigeration system, a shortage of refrigerant is indicated byA.the compressor short cycling on high pressure cut out switchB.high suction pressureC.high head pressureD.bubbles in the sight glass
考题
If the suction pressure at the refrigeration compressor is below normal, the cause can beA.refrigerant overchargeB.overfeeding by the expansion valveC.a restricted suction strainerD.due to short cycling of the compress
考题
Sweating of the refrigeration system compressor crankcase is caused by_______ .A.too much superheatB.insufficient superheatC.suction pressure too lowD.excessive refrigerant returning to the compressor
考题
Which of the following problems could cause the high pressure cutout switch to shut down the compressor in a refrigeration system?A.A shortage of liquid refrigerant.B.Excessive frost on the evaporator.C.Excessive condenser cooling water.D.Insufficient condenser cooling water flow.
考题
In a chilled(冷的) water air conditioning unit using a reciprocating compressor, the refrigerating effect of the primary refrigerant can be increased by ______.A.increasing refrigerant pressure in the coilB.increasing chilled water flow through the coolerC.sub-cooling the refrigerant in the condenserD.superheating the refrigerant in the compressor
考题
单选题Low compressor head pressure in a refrigeration system can be caused by（）.A
insufficient condenser cooling waterB
excessive condenser cooling waterC
air in the refrigeration systemD
excessive refrigerant in the system
考题
单选题A refrigeration system compressor crankcase is sweating or unusually coldThis is an indication of（）.A
a shortage of refrigerant in the systemB
air in the systemC
an accumulation of liquid refrigerant in the crankcaseD
a shortage of oil in the crankcase
考题
单选题If a refrigeration system compressor crankcase is sweating, you should （）.A
add refrigerant to the systemB
adjust the thermal expansion valve to the proper settingC
adjust the float valve to the proper holding pressureD
open the hand expansion valve
考题
单选题Which of the conditions listed will cause a refrigeration compressor to run constantly without simultaneously decreasing the temperature in the refrigerated space?（）A
Shortage of refrigerant oilB
Slight shortage of refrigerantC
Excessive condenser cooling water flowD
Faulty expansion valve
考题
单选题Insufficient refrigerant in a refrigeration plant may result in （）.A
high discharge pressureB
frosting of the crankcaseC
high temperature of the overboard waterD
low suction pressure of compressor
考题
单选题If a refrigeration system were short of refrigerant, the condition would result in （）.A
continuous running of the compressorB
high suction pressureC
high discharge pressureD
short cycling of the compressor on the water failure switch
考题
单选题Refrigerant is normally sub-cooled in a refrigeration or air conditioning system condenser to （）.A
maintain adequate coil back pressureB
prohibit flashing in the liquid lineC
reduce refrigerant volume in the systemD
reduce compressor discharge line loading
考题
单选题If a refrigeration compressor is running continuously without lowering the temperature in the refrigerated space, the trouble may be （）.A
a shortage of compressor oilB
warm food in the refrigeratorC
excessive condenser cooling waterD
a shortage of refrigerant
考题
单选题If a refrigeration compressor will not start, the reason may be （）.A
the pressure regulating valve is not closingB
an excessive lack of refrigerant in the systemC
badly leaking discharge valvesD
worn piston rings
考题
单选题Before charging a refrigeration unit, the refrigerant charging lines should be（）A
flushed with clean refrigerant oilB
purged with the refrigerantC
washed with an ammonia and alcohol solutionD
grounded to compressor
考题
单选题If the refrigeration compressor crankcase is sweating, the cause may be due to （）.A
a shortage of refrigerantB
the compressor running continuouslyC
liquid refrigerant returning to the compressorD
the compressor short cycling on the high pressure cutout
考题
单选题Foaming of the oil in a refrigeration compressor crankcase is caused by （）.A
refrigerant boiling out of solution from the lube oilB
liquid refrigerant flooding the compressor and systemC
lube oil viscosity being reduced by refrigerant dilutionD
compressor suction pressure suddenly increasing
考题
单选题In a chilled water air conditioning unit using a reciprocating compressor, the refrigerating effect of the primary refrigerant can be increased by （）.A
increasing refrigerant pressure in the coilB
increasing chilled water flow through the coolerC
sub-cooling the refrigerant in the condenserD
superheating the refrigerant in the compressor
考题
单选题An excessive charge of refrigerant in an air-cooled refrigeration system can cause （）.A
oil foaming in the compressorB
higher than normal suction and discharge pressures with a higher box temperatureC
higher than normal discharge pressure with a normal box temperatureD
the compressor to run continuously
考题
单选题Which of the following may cause that the compressor cuts off on high pressure cutout in a refrigeration plant? （） (1) faulty condensing (2) too few refrigerant (3) high discharge pressureA
any of (1) and (3)B
any of (1) and (2)C
any of (2) and (3)D
any of (1), (2) and (3)
考题
单选题Under normal conditions, the refrigerant enters the compressor in an operating refrigeration system as a （）.A
liquidB
dry saturated gasC
wet saturated gasD
superheated vapor
考题
单选题Sweating of the refrigeration system compressor crankcase is caused by （）.A
too much superheatB
insufficient superheatC
suction pressure too lowD
excessive refrigerant returning to the compressor
考题
单选题When a refrigeration compressor has developed a high head pressure as a result of a refrigerant overcharge, you should （）.A
increase the amount of cooling water to the condenserB
decrease the amount of cooling water to the condenserC
add more refrigerant to the systemD
remove some refrigerant from the system
考题
单选题The receiver used in a refrigeration system（）A
stores liquid refrigerantB
collects non-condensable gasesC
allows refrigerant sub-coolingD
prevents compressor surging
热门标签
最新试卷