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
A pressure drop through the refrigerant liquid line may cause （）.
A
solenoid valve to seize
B
compressor to hunt
C
formation of flash gas in the liquid line
D
expansion valve to freeze open
参考答案
参考解析
解析：
暂无解析
更多 “单选题A pressure drop through the refrigerant liquid line may cause （）.A solenoid valve to seizeB compressor to huntC formation of flash gas in the liquid lineD expansion valve to freeze open” 相关考题
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
The temperature of the refrigerant in the evaporator coil depends mostly upon the ___.A.refrigerant pressure in the evaporatorB.cooling water temperature to the condenserC.heat load in the refrigerator compartmentD.solenoid valve in the liquid line
考题
To add refrigerant to the low side of an air conditioning system, the refrigerant should be introduced through the_______ .A.suction service valve as a vaporB.suction service valve as a liquidC.discharge service valve as a vaporD.charging valve as a liquid
考题
If the superheat value of a thermostatic expansion valve is set too low, the _.A.the suction line will be abnormally cold and liquid may slug back to the compressorB.the suction line will be hot due to a reduced amount of refrigerant returning to the compressorC.the temperature of the refrigerant within the condenser will remain the sameD.the temperature of the refrigerant passing through the sub-cooler will decrease
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Which of the problems listed could be indicated if a sight glass in the refrigerant liquid line is full of bubbles?（）A
Proper refrigerant chargeB
Faulty expansion valveC
Insufficient refrigerantD
Solenoid valve stuck open
考题
单选题As the refrigerant passes through the valve orifice, its pressure is reduced and part of the refrigerant turns into （）.A
liquidB
oily mixtureC
emulsionD
vapor
考题
单选题Refrigerant enters the condenser as a （）.A
high pressure liquidB
low pressure vaporC
high pressure vaporD
low pressure liquid
考题
单选题In an operating refrigeration system low on refrigerant, a liquid line sight glass will（）A
be clearB
be blueC
be light greenD
show bubbles
考题
单选题An increasing head pressure in a refrigeration system, without any corresponding change in the cooling water inlet temperature, would probably be caused by （）.A
restriction in refrigerant pipingB
air and non-condensable gases in the condenserC
water in the refrigerantD
flooding back of liquid refrigerant from the evaporator
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The only means of removing the latent heat of condensation from a refrigerant in the normal refrigeration cycle is by （）.A
passing it through the expansion valveB
condensing refrigerant in the system condenserC
passing the gaseous refrigerant through the heat interchanger on the suction side of the compressorD
maintaining a high pressure on the systems receiver
考题
单选题A liquid indicator sight glass is useful in determining whether or not a refrigeration system is sufficiently chargedIt is generally located in the（）.A
high pressure liquid lineB
low pressure liquid lineC
high pressure vapor lineD
low pressure vapor line
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The temperature of the refrigerant in the evaporator coil depends mostly upon the （）.A
refrigerant pressure in the evaporatorB
cooling water temperature to the condenserC
heat load in the refrigerator compartmentD
solenoid valve in the liquid line
考题
单选题Moisture in the refrigerant may （）.A
freeze on the expansion valve seat and reduce the flow of liquid refrigerantB
emulsify the oil in the condenserC
freeze in the king valveD
clog the oil trap
考题
单选题In a compression refrigeration plant the hot, high pressure refrigerant gas is cooled by the sea water and becomes liquid in the （）.A
compressorB
condenserC
throttle valveD
evaporator
考题
单选题The thermal expansion valve reacts directly to the （）A
temperature in the space being cooledB
liquid refrigerant pressure at the solenoid valveC
pressure drop across the evaporator coilsD
refrigerant gas superheat at the coil outlet
考题
单选题The static suction head of is the （）A
distance of the suction liquid level above the line of the pumpB
distance the suction liquid level is below the center line of the pumpC
force necessary to overcome frictional losses in the pump and pipingD
amount in inches of mercury the total suction head is below atmospheric pressure
考题
单选题To add refrigerant to the low side of an air conditioning system, the refrigerant should be introduced through the （）A
suction service valve as a vaporB
suction service valve as a liquidC
discharge service valve as a vaporD
charging valve as a liquid
考题
单选题“Flooding back” is a condition where the liquid refrigerant （）.A
vaporizes in the condenserB
reaches the compressor through the suction lineC
flashes in the liquid lineD
condenses in the receiver
考题
单选题While troubleshooting a refrigeration system for low head pressure, liquid refrigerant flooding back from the evaporator is determined to be the causeIt may be necessary to （）.A
change the expansion valve adjustmentB
readjust the water regulating valve to increase the flow of waterC
purge air from the condenserD
clean the waterside of the condenser
考题
单选题The principal purpose of sub-cooling liquid refrigerant prior to its entering the expansion valve is to （）.A
increase the refrigerating effect, by decreasing the amount of flash gasB
allow the refrigerant to enter the throttling device in a saturated conditionC
increase the refrigerating effect by increasing the amount of flash gasD
minimize the temperature drop of the liquid as it passes through the solenoid valve to the outlet side
考题
单选题The purpose of the low pressure cut-out switch is to （）.A
maintain liquid refrigerant at the suction of the compressorB
maintain a preset suction pressure to the compressorC
start and stop the compressor at preset operating pressuresD
operate at minimum efficiency
考题
单选题A pressure drop in the liquid line of a refrigeration system may cause（）A
the solenoid valve to seizeB
the compressor to huntC
flash gas to form in the liquid lineD
the expansion valve to freeze open
考题
单选题A sight glass is installed in the liquid line to indicate the condition of the refrigerant charge and may also indicate the （）.A
condition of the expansion valveB
moisture in the systemC
condition of the compressor suction valvesD
condenser temperature
考题
单选题The presence of bubbles in a refrigeration system liquid line may （）.A
promote refrigerant dehydrationB
be absorbed in the receiverC
cause low condensing pressureD
carry moisture and lead to corrosion
热门标签
最新试卷
