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
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 oil
B
Slight shortage of refrigerant
C
Excessive condenser cooling water flow
D
Faulty expansion valve
参考答案
参考解析
解析:
暂无解析
更多 “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” 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
Which of the listed conditions can be considered as the single greatest cause of accidents?A.SpeedB.Excessive knowledge or skillC.Human errorD.Excitement
考题
单选题When lighting off an auxiliary boiler, which of the problems listed could cause the burners to sputter?()A
cold fuel oilB
low fuel oil pressureC
low atomizing steam pressureD
water in the fuel oil
考题
单选题Which of the listed problems can be a cause of low compression pressure in a diesel engine?()A
clogged air filterB
compression strokeC
burned exhaust valvesD
all of the above
考题
单选题Which of the listed conditions can cause a diesel engine to use too much lube oil?()A
Dirty lube oil filterB
Too much piston ring wearC
High lube oil viscosityD
Low lube oil temperature
考题
单选题Which of the listed operations will cause an automatically controlled refrigeration compressor to restart?()A
Closing of the solenoid valveB
Closing of the expansion valveC
An increase in the suction pressureD
Decreasing the suction pressure
考题
单选题The three conditions which cause engine shutdown are overspeed,low lube oil pressure,and().A
High lube oil pressureB
High jacket water pressureC
High jacket water temperatureD
Low jacket water pressure
考题
单选题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 refrigerantB
Excessive frost on the evaporatorC
Excessive condenser cooling waterD
Insufficient condenser cooling water flow
考题
单选题Which of the listed diesel engine operating conditions should be checked immediately after any diesel engine is started?()A
Exhaust temperatureB
Lube oil levelC
Lube oil pressureD
Water level in the expansion tank
考题
单选题Which of the listed conditions will occur if a diesel engine exhaust valve is leaking?()A
Loss of compression for that cylinderB
Misfiring or rough runningC
Damage to the valveD
All of the above
考题
单选题Which of the listed cylinder liner surface conditions indicates proper lubrication?()A
Dull black appearanceB
Bright appearanceC
Thin layer of lacquerD
Thick oily film
考题
单选题Which of the listed conditions can cause lacquer to be deposited on a piston skirt?()A
High sulphur content fuelB
High lube oil temperaturesC
High vanadium content fuelD
Excessive piston slap
考题
单选题Which of the listed conditions can be considered as the single greatest cause of accidents?()A
SpeedB
Excessive knowledge or skillC
Human errorD
Excitement
考题
单选题As engine RPM is increased from idle speed to full load speed, which of the conditions listed will decrease?()A
Compression ratioB
Fuel/Air ratioC
Compression pressureD
Lube oil pressure
考题
单选题Which of the listed conditions can be used to determine if lube oil has been diluted by fuel? ()A
Viscosity is decreasedB
Octane number is alteredC
Pump speed is decreasedD
Blower’s speed is decreased
考题
单选题Which cause of following will not lead to refrigeration plant short-cycle?()A
lack of refrigerantB
refrigerant with much waterC
set defectively low pressure relayD
no cooling water
考题
单选题Which of the following conditions could be a cause of excessive fuel dilution of diesel engine lube oil?()A
Leaking fuel injectorsB
Lower than normal compressionC
Delayed fuel injectionD
All of the above are correct
考题
单选题Which of the conditions listed represents the greatest effect of excess frost accumulation on the evaporator coils?()A
Keeps the refrigerated space coolerB
Reduces the efficiency of the plantC
Takes the load off the compressorD
Has no affect on the system
考题
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
考题
单选题Under which of the listed conditions can the engine room retake the throttle control from the bridge().A
Any time it is deemed necessaryB
Only with the masters permissionC
After a 10 minute delay to the input commandD
Only after the throttle has been placed in stop
考题
单选题Which of the listed conditions will cause the feed water that has not flashed to vapor in the first-stage of a flash evaporator, to flow into the second-stage?()A
Gravity siphon effectB
Higher vacuum in the second-stageC
Difference in brine density between first and second stagesD
lower pressure in first-stage
考题
单选题Which of the listed statements is correct concerning refrigeration systems?()A
Dehydrators must be used continuously in a refrigeration systemB
A 25 ton refrigeration system has the same cooling effect as melting 25 tons of ice in 24 hoursC
A thermostatic expansion valve is used to control refrigerated space temperatureD
The liquid receiver functions to collect and remove non- condensable gases
考题
单选题Which of the listed refrigeration system components keeps the refrigerant circulating through the system?()A
Expansion valveB
CondenserC
EvaporatorD
Compressor
考题
单选题Which of the following conditions would cause carbon deposits to form in the piston ring belt of a diesel engine?()A
faulty combustionB
excessive ring temperatureC
over lubricationD
all of the above
考题
单选题When one cylinder has a lower compression pressure and higher exhaust gas temperature than any of the other engine cylinders, which of the conditions listed will indicated?()A
Advanced ignitionB
Clogged air intakeC
Leaky exhaust valveD
High exhaust pressure
考题
单选题Which of the listed components is considered to separate the high pressure side of a refrigeration cycle from the low pressure side of the cycle?()A
The condenser and the expansion valveB
The king valve and the solenoid valveC
The compressor and the expansion valveD
The condenser and the solenoid valve
考题
单选题Which of the problems listed would came the discharge temperature of an R-12 refrigeration compressor to increase?()A
Thermal expansion valve frozen openB
Suction gas heat exchanger bypassedC
Condenser clogged or fouledD
High pressure cutout switch inoperative
热门标签
最新试卷