Technician Grade II (Refrigeration Mechanic) – Kerala Cooperative Milk Marketing Federation Limited
PROVISIONAL ANSWER KEY
Question Paper Code: 73/2022/OL
Category Code: 014/2022
Exam: Technician Grade II (Refrigeration Mechanic)
Date of Test 31-08-2022
Department Kerala Cooperative Milk Marketing Federation Limited
Alphacode A
Question1:-Which extinguishes the fire of flammable liquids ?
A:-Water
B:-Air
C:-𝐶𝑂2
D:-Oil
Correct Answer:- Option-C
Question2:-The best way of avoiding accidents is by
A:-Doing work in ancient way
B:-Doing work in one’s own way
C:-Observing safety rules related to job, machine and work place
D:-Using safety equipment
Correct Answer:- Option-C
Question3:-What is smoothering in fire extinguishing ?
A:-Pouring of CTC
B:-Flashing with dry powder
C:-Use water to low temperature
D:-Stop the supply of oxygen
Correct Answer:- Option-D
Question4:-An outside micrometer has a negative error. The correct reading can be taken by
A:-Adding the negative error in the actual reading.
B:-Deducting the negative error from the actual reading
C:-Adding twice the negative error in the actual reading.
D:-Deducting twice the negative error from the actual reading.
Correct Answer:- Option-A
Question5:-Which type of taper is provided in the drill shank ?
A:-Pin taper
B:-Metric taper
C:-Morse taper
D:-Jerno taper
Correct Answer:- Option-C
Question6:-Why the cutting faces of files are slightly bellied on lengthwise ?
A:-Get proper grip over workpiece
B:-Filing flat surfaces is made easier
C:-Permit clearance between file face and the workpiece
D:-Ensure more pressure on workpiece while filing
Correct Answer:- Option-B
Question7:-Which one of the following sheets is used for making highly corrosive acid tanks ?
A:-Black iron sheets
B:-Galvanised iron sheets
C:-Stainless steel sheets
D:-Lead sheets
Correct Answer:- Option-D
Question8:-What is the use of feeler gauge ?
A:-Check the width
B:-Check the height
C:-Check the length
D:-Check the gap between the mating parts
Correct Answer:- Option-D
Question9:-Which type of screw threads are rounded at the crest and root ?
A:-B.A. thread
B:-B.S.F. thread
C:-B.S.W. thread
D:-A.C.M.E. thread
Correct Answer:- Option-B
Question10:-Which tool is used for trimming the edges of a sheet metal cylinder ?
A:-Straight snips
B:-Bent snips
C:-Tube cutter
D:-Scissors
Correct Answer:- Option-B
Question11:-The diode used for voltage regulation is
A:-Rectifier diode
B:-Zener diode
C:-Signal diode
D:-Varicap diode
Correct Answer:- Option-B
Question12:-Which tool is used for bending, seaming and forming of sheet metal ?
A:-Bench vice
B:-Hand vice
C:-Stakes
D:-Shear
Correct Answer:- Option-C
Question13:-One of the functions of electrode coating is
A:-To increase welding current
B:-To stabilize the arc
C:-To prevent rusting
D:-To control arc temperature
Correct Answer:- Option-B
Question14:-The correct flame for preheating before cutting is
A:-Oxidizing flame
B:-Neutral flame
C:-Carburizing flame
D:-Slightly carburizing flame
Correct Answer:- Option-B
Question15:-What is the tool used to remove slag from the welding ?
A:-Tongs
B:-Chipping hammer
C:-Cross pean hammer
D:-Ball pean hammer
Correct Answer:- Option-B
Question16:-Which motor has the least starting torque ?
A:-CSIR
B:-CSR
C:-RSIR
D:-PSC
Correct Answer:- Option-C
Question17:-The squirel cage three phase induction motor is started by
A:-DOL starter
B:-Star Delta starter
C:-Both (1) and (2)
D:-Stator-Rotor starter
Correct Answer:- Option-C
Question18:-Which electronic component is the voltage regulator ?
A:-Zener diode
B:-Transistor
C:-Triac
D:-Diac
Correct Answer:- Option-A
Question19:-Which gas is produced by the chemical reaction of carbide and water ?
A:-Oxygen
B:-Nitrogen
C:-Acetylene
D:-Carbondioxide
Correct Answer:- Option-C
Question20:-A flaring tool consist of
A:-Flaring block and yoke
B:-Flaring cone and block
C:-Flaring bush and cone
D:-Flaring cone and yoke
Correct Answer:- Option-A
Question21:-The size of tube cutter can be specified by
A:-Length of tube cutter
B:-Cutting wheel size
C:-Maximum diameter of tube which it can cut
D:-Cutting wheel thickness
Correct Answer:- Option-C
Question22:-A lever type tube bender can form bends up to
A:-90°
B:-135º
C:-45º
D:-180º
Correct Answer:- Option-D
Question23:-Pinching tool is used for
A:-Enlarging copper tube ends
B:-Remove burrs from tube end
C:-Sealing or closing the copper tubes
D:-Fixing copper tubes in swaging tool
Correct Answer:- Option-C
Question24:-Heat required to increase the temperature of 1 gram of water by 1 degree centigrade is called
A:-Calorie
B:-BTU
C:-CHU
D:-None of these
Correct Answer:- Option-A
Question25:-The boiling point of water in Fahrenheit scale is
A:-100º
B:-232º
C:-212°
D:-32º
Correct Answer:- Option-C
Question26:-The freezing point of mercury is
A:-− 45ºC
B:-– 39ºC
C:-– 4ºC
D:-– 20ºC
Correct Answer:- Option-B
Question27:-The heat required for changing the state of any object without changing its temperature is called
A:-Sensible heat
B:-Latent heat
C:-Specific heat
D:-None of these
Correct Answer:- Option-B
Question28:-Which thermodynamic law presents the concept of temperature ?
A:-Zeroth law
B:-First law
C:-Second Law
D:-Third law
Correct Answer:- Option-A
Question29:-Dry ice is
A:-Solid carbon dioxide
B:-Solid nitrogen
C:-Solid hydrogen
D:-Solid oxygen
Correct Answer:- Option-A
Question30:-The liquid refrigeration system is also called
A:-Chemical refrigeration system
B:-Expandable refrigeration system
C:-Water vapour system
D:-Both (1) and (2)
Correct Answer:- Option-D
Question31:-In vapour absorption system which energy is used ?
A:-Mechanical energy
B:-Heat energy
C:-Chemical energy
D:-Potential energy
Correct Answer:- Option-B
Question32:-The cylinder volume between TDC and BDC is known as
A:-Clearance volume
B:-Total volume
C:-Swept volume
D:-All of these
Correct Answer:- Option-C
Question33:-A centrifugal compressor is also called
A:-Turbo compressor
B:-Radial compressor
C:-Scroll compressor
D:-Both (1) and (2)
Correct Answer:- Option-D
Question34:-An example of dynamic compressor is
A:-Rotary vane compressor
B:-Reciprocating compressor
C:-Rotary scroll compressor
D:-Centrifugal compressor
Correct Answer:- Option-D
Question35:-Rotary screw compressor is used for industrial and commercial applications with a capacity range of
A:-5 to 10 tons
B:-20 to 750 tons
C:-11 to 15 tons
D:-Above 1000 tons
Correct Answer:- Option-B
Question36:-The size of the gasket specified by its
A:-Material
B:-Thickness
C:-Strength
D:-Both (1) and (3)
Correct Answer:- Option-B
Question37:-The main disadvantage of water cooled condenser is
A:-Expensive
B:-Low heat transfer rate
C:-Used in low capacity plants
D:-They have fans mounted in them
Correct Answer:- Option-A
Question38:-The condenser both air and water used as cooling medium is
A:-Evaporative condenser
B:-Plate type condenser
C:-Shell and coil condenser
D:-Shell and tube condenser
Correct Answer:- Option-A
Question39:-The efficiency of condenser increases due to
A:-De scaling
B:-Scaling
C:-Painting
D:-Both (2) and (3)
Correct Answer:- Option-A
Question40:-In natural cooling tower, its sides are
A:-Closed
B:-Opened
C:-Partially opened
D:-None of these
Correct Answer:- Option-B
Question41:-In hard water the calcium carbonate contents is
A:-Less than 60 PPM
B:-120 to 180 PPM
C:-More than 180 PPM
D:-60 to 120 PPM
Correct Answer:- Option-B
Question42:-The difference between the cooling tower water inlet and outlet temperature is known as
A:-Approach
B:-Blow down
C:-Range
D:-Efficiency
Correct Answer:- Option-C
Question43:-Thermostatic expansion valves are generally set for a super heat of around
A:-10 to 15ºC
B:-0 to 3ºC
C:-4.4 to 5.5ºC
D:-16 to 20ºC
Correct Answer:- Option-C
Question44:-In which type of expansion valve has high efficiency ?
A:-Capillary Tube
B:-Automatic expansion valve
C:-Hand expansion valve
D:-Thermostatic expansion valve
Correct Answer:- Option-D
Question45:-The location of an expansion valve in a system is
A:-Between condenser and drier
B:-Between compressor and condenser
C:-Between evaporator and accumulator
D:-Between liquid receiver and evaporator
Correct Answer:- Option-D
Question46:-The evaporator is also known as
A:-Chilling coil
B:-Freezing coil
C:-Cooling coil
D:-All of the above
Correct Answer:- Option-D
Question47:-The evaporator which is used in high capacity refrigeration systems is
A:-Dry expansion evaporator
B:-Plate surface evaporator
C:-Flooded evaporator
D:-Bare tube evaporator
Correct Answer:- Option-C
Question48:-Which process is done first in split AC for shifting from one place to another ?
A:-Flushing
B:-Evacuation
C:-Pump down
D:-Vacuumisation
Correct Answer:- Option-C
Question49:-A compressor coupled to a motor externally is called
A:-Sealed compressor
B:-Semi sealed compressor
C:-Open type compressor
D:-None of the above
Correct Answer:- Option-C
Question50:-The device which divides the high pressure side and the low pressure side of a refrigerating system is known as
A:-Condenser
B:-Evaporator
C:-Receiver
D:-Expansion device
Correct Answer:- Option-D
Question51:-The leakage in a refrigeration system using ammonia is detected by
A:-Halide torch
B:-Sulphur sticks
C:-Soap and water
D:-All of these
Correct Answer:- Option-B
Question52:-One ton of refrigeration is equal to
A:-2880,000 BTU/hr
B:-20,000 BTU/hr
C:-12,000 BTU/hr
D:-200 BTU/hr
Correct Answer:- Option-C
Question53:-The undesirable property of a refrigerant is
A:-Non toxic
B:-Non flammable
C:-Non explosive
D:-High boiling point
Correct Answer:- Option-D
Question54:-The conditioned air supplied to the room must have the capacity to take up
A:-Room sensible heat load only
B:-Room latent heat load only
C:-Both room sensible heat and latent heat loads
D:-None of the above
Correct Answer:- Option-C
Question55:-Thermostatic expansion valve is used to maintain
A:-Constant degree of superheat
B:-Constant degree of sub-cooling
C:-Constant degree of superheat and sub-cooling
D:-None of these
Correct Answer:- Option-A
Question56:-In a refrigeration system, why are expansion devices located closer to the evaporator ?
A:-To avoid the flow of refrigerant
B:-To minimize the heat gain
C:-To ease the flow of refrigerant
D:-To maximize the heat gain
Correct Answer:- Option-B
Question57:-The window type AC is installed slight slanting at the back. What is the reason for doing so ?
A:-To get more air flow on condenser surface
B:-To minimize sound level due to vibration
C:-To make condensate water flow into the drain pipe
D:-To get more cooling effect inside the room
Correct Answer:- Option-C
Question58:-What type of compressor motor is used in inverter split AC ?
A:-Constant speed compressor motor
B:-Centrifugal compressor motor
C:-Open type compressor motor
D:-Variable speed motor
Correct Answer:- Option-D
Question59:-Which of the following is not an advantage of capillary tube ?
A:-The cost of capillary tube is less
B:-A high starting motor is not required
C:-No receiver is needed
D:-A capillary tube designed for a specific condition will also work efficiently for other conditions
Correct Answer:- Option-D
Question60:-The CSIR wiring of visible cooler has no
A:-Starting capacitor
B:-Running capacitor
C:-Relay
D:-OLP
Correct Answer:- Option-B
Question61:-What is the value of starting capacitor used for 1.5 TR capacity window AC ?
A:-40 to 60 MFD
B:-80 to 100 MFD
C:-130 to 160 MFD
D:-150 to 160 MFD
Correct Answer:- Option-B
Question62:-What is the cause for water cooler runs continuously ?
A:-Outside low temperature
B:-Poor insulation
C:-Correct charge
D:-Less water consumption
Correct Answer:- Option-B
Question63:-Separate thermostats are used in split AC units of the type
A:-Ductable split unit
B:-Multi split unit
C:-Ceiling mounted unit
D:-Floor mounted unit
Correct Answer:- Option-B
Question64:-Which of the following statement is wrong ?
A:-The value of C.O.P. is always greater than one
B:-In a vapour compression system, the condition of refrigerant before entering the compressor is dry saturated vapour
C:-The space between the saturated liquid line and saturated vapour line, in a pressure enthalpy chart, is wet vapour region
D:-None of the above
Correct Answer:- Option-D
Question65:-Materials form deposits inside the condenser water tubes is called
A:-Water rusting
B:-Water corrosion
C:-Water fouling
D:-Water failing
Correct Answer:- Option-C
Question66:-Why are ice cans made tapered in height ?
A:-To reduce weight
B:-To facilitate dumping
C:-To improve appearance
D:-All of the above
Correct Answer:- Option-B
Question67:-What is the gas used in ice plants ?
A:-Nitrogen
B:-Ammonia
C:-Laughing gas
D:-All of the above
Correct Answer:- Option-B
Question68:-The most common insulating material used in deep freezer is
A:-PUF
B:-Thermocool
C:-Cork
D:-Glass wool
Correct Answer:- Option-A
Question69:-Which type of evaporator is used in household refrigerators ?
A:-Frosting evaporator
B:-Defrosting evaporator
C:-Non-frosting evaporator
D:-Non-corrosive evaporator
Correct Answer:- Option-A
Question70:-What is Air Condititiong ?
A:-Air conditioning is the process of adding heat and increasing the humidity
B:-Air conditioning is the process of removing heat and controlling the humidity of air in a closed space
C:-Air conditioning is the process of controlling air moisture in an open area by adding heat
D:-None of the mentioned
Correct Answer:- Option-B
Question71:-Which of the following is not a factor affecting the capacity of evaporator ?
A:-Velocity of refrigerant
B:-Thickness of the evaporator coil wall
C:-Material
D:-Evaporator pressure
Correct Answer:- Option-D
Question72:-The grill of an air conditioner should be washed with
A:-Carbon tetrachloride
B:-Petrol
C:-Soap solution
D:-Hydrochloric acid
Correct Answer:- Option-C
Question73:-Which arrangement avoids cooling water overflow in storage type water cooler ?
A:-Bubbler
B:-Faucet
C:-Float
D:-Tap
Correct Answer:- Option-C
Question74:-In a vapour compression cycle the condition of refrigerant is saturated liquid
A:-After passing through the condenser
B:-Before passing through the condenser
C:-After passing through the expansion throttle valve
D:-Before entering the expansion valve
Correct Answer:- Option-A
Question75:-Which component is used to maintain the brine solution temperature evenly in a Ice candy plant ?
A:-Humidistat
B:-Blower
C:-Agitator
D:-Fan
Correct Answer:- Option-C
Question76:-In an Ice plant where the refrigerant after condensation is stored ?
A:-Accumulator
B:-Liquid receiver
C:-Evaporator
D:-Expansion device
Correct Answer:- Option-B
Question77:-Brine solution is the mixture of
A:-Calcium chloride and water
B:-Calcium carbonate and water
C:-Calcium hydroxide and water
D:-Calcium silicate and water
Correct Answer:- Option-A
Question78:-How the walk in coolers wall panels are connected ?
A:-Through gasket
B:-Through ceiling panels
C:-Through wood panel
D:-Through in build lock
Correct Answer:- Option-D
Question79:-Which indication gives if the red bulb blinking outside the cold room ?
A:-Door is left open
B:-Compressor has tripped
C:-Someone is locked inside
D:-Decrease in refrigerant level
Correct Answer:- Option-C
Question80:-Which electrically operated valve is used in cold storage plants ?
A:-Service valve
B:-King valve
C:-Butterfly valve
D:-Solenoid valve
Correct Answer:- Option-D
Question81:-Why the relative humidity is kept above 90% in cold storage plants storing vegetables ?
A:-To prevent moisture loss
B:-To improve moisture loss
C:-To reduce weight
D:-To increase weight
Correct Answer:- Option-A
Question82:-Specific humidity is also called
A:-Saturation humidity
B:-Absolute humidity
C:-Humidity ratio
D:-Relative humidity
Correct Answer:- Option-C
Question83:-Wet bulb temperature of air whose relative humidity is 100% will be
A:-Equal to dew point temperature
B:-Greater than dew point temperature
C:-Less than dew point temperature
D:-More or less depending dry bulb temperature
Correct Answer:- Option-A
Question84:-What is Room Sensible Heat Factor (RSHF) ?
A:-RLH / (RSH+RLH)
B:-RSH/(RSH+RLH)
C:-RSH/RLH
D:-RLH/RSH
Correct Answer:- Option-B
Question85:-Standard atmospheric pressure is
A:-101.325 bar
B:-10.1325 bar
C:-1.03325 bar
D:-1.01325 bar
Correct Answer:- Option-D
Question86:-What is one of the daily routine maintenance in a central Ac plant ?
A:-Cooling tower sump cleaning
B:-Descaling of condenser
C:-Checking of refrigerant level, cold air temperature
D:-Liquid line drier cleaning
Correct Answer:- Option-C
Question87:-In summer air conditioning the process is
A:-Sensible cooling
B:-Cooling and dehumidification
C:-Heating and humidification
D:-Cooling and humidification
Correct Answer:- Option-B
Question88:-Which controls the refrigerant flow in a package AC unit ?
A:-Thermostat
B:-King valve
C:-Evaporator
D:-Expansion valve
Correct Answer:- Option-D
Question89:-VRV stands for
A:-Variable Refrigerant value
B:-Variable Recirculated Value
C:-Variable Recirculated Volume
D:-Variable Refrigerant Volume
Correct Answer:- Option-D
Question90:-Glass wool is an example for
A:-Flake insulation
B:-Fibrous insulation
C:-Granular insulation
D:-Cellular insulation
Correct Answer:- Option-B
Question91:-Which type of duct requires least material for carrying air ?
A:-Circular
B:-Rectangular
C:-Square
D:-Trapezoidal
Correct Answer:- Option-A
Question92:-AHU stands for
A:-Air Humidity Unit
B:-Air Humidity Utility
C:-Air Handling Unit
D:-Air Having Unit
Correct Answer:- Option-C
Question93:-The ducts are mostly made by
A:-Iron sheet
B:-Glass
C:-Wood
D:-Galvanized Iron sheet
Correct Answer:- Option-D
Question94:-The space between the main ceiling and false ceiling is referred as
A:-Damper
B:-Diffuser
C:-Plenum
D:-Ventilator
Correct Answer:- Option-C
Question95:-In HEPA filter, what stands for HEPA ?
A:-Height Efficient Particular Air
B:-High Efficiency Particulate Air
C:-Height Efficient Pre Air
D:-High Efficiency Prior Air
Correct Answer:- Option-B
Question96:-In an electronic filter the air is filtered by passing through a
A:-Electromotive field
B:-Electrodynamic field
C:-Electromagnetic field
D:-Electrostatic field
Correct Answer:- Option-D
Question97:-Which filter removes smoke and other odours ?
A:-Electronic filter
B:-Fine filter
C:-Coarse filter
D:-Pre filter
Correct Answer:- Option-A
Question98:-The condenser of car AC is
A:-Evaporative cooled
B:-Water cooled
C:-Air cooled
D:-Both air cooled and oil cooled
Correct Answer:- Option-C
Question99:-For what purpose dye is adding to the car AC system with refrigerant ?
A:-To lubricating the compressor
B:-To identify gas leak
C:-For easy refrigerant flow
D:-For better cooling
Correct Answer:- Option-B
Question100:-The refrigerant used in automobile AC is
A:-R134A
B:-R600A
C:-R717
D:-R290
Correct Answer:- Option-A
