Refrigerant Machine Operator Test #3

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| By Catherine Halcomb
Catherine Halcomb
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  • 1/100 Questions

    A COMPRESSOR THAT USES A SHAFT WITH A MECHANICAL SEAL, WHAT IS THE VALVE PLATE MADE OF?

    • METAL/CARBON
    • PLASTIC
    • RUBBER
    • SILICON
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About This Quiz

A refrigerant machine operator is an important person for the transportation of items that need a specified degree of temperature. Are you one of them or just interested? If so, take up the test and all the best.

Refrigerant Machine Operator Test #3 - Quiz

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  • 2. 

    WHAT DOES A FILTER DRIER DO? 

    • REMOVES PARTICLES

    • REMOVES MOISTURE

    • REMOVES ACID

    • ALL OF THE ABOVE

    Correct Answer
    A. ALL OF THE ABOVE
    Explanation
    A filter drier is a device used in HVAC systems to remove particles, moisture, and acid from the refrigerant. It helps to maintain the cleanliness and efficiency of the system by preventing clogs, corrosion, and damage caused by these contaminants. By removing particles, moisture, and acid, the filter drier ensures that the refrigerant circulates properly and that the system operates effectively. Therefore, the correct answer is "ALL OF THE ABOVE."

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  • 3. 

    REGARDLESS OF THE SAFETY CLASSIFICATION OF THE REFRIGERANT IN USE, IN THE EVENT OF REFRIGERANT ESCAPE, THE RMO SHOULD BE AWARE OF:

    • A REFRIGERANT FIRE

    • REFRIGERANT POISONING

    • OXYGEN DEPRIVATION

    • ATMOSPHERIC SUPERHEATING

    Correct Answer
    A. OXYGEN DEPRIVATION
    Explanation
    In the event of a refrigerant escape, regardless of the safety classification of the refrigerant in use, the RMO (Responsible Managing Officer) should be aware of oxygen deprivation. When refrigerant escapes, it can displace the oxygen in the surrounding area, leading to a lack of oxygen for individuals in that space. This can be dangerous and potentially life-threatening if not addressed promptly. Therefore, it is crucial for the RMO to be aware of this risk and take appropriate measures to ensure the safety of all personnel.

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  • 4. 

    THE TRUE POWER CONSUMED BY AN INDUCTION MOTOR CAN BEST BE DESCRIBED BY THE FOLLOWING FORMULA:

    • CURRENT x VOLTAGE x POWER FACTOR

    • CURRENT x VOLTAGE

    • VOLTAGE x RESISTANCE

    • CURRENT x RESISTANCE

    Correct Answer
    A. CURRENT x VOLTAGE x POWER FACTOR
    Explanation
    The true power consumed by an induction motor can best be described by the formula CURRENT x VOLTAGE x POWER FACTOR. This formula takes into account the current flowing through the motor, the voltage applied to it, and the power factor, which represents the efficiency of the motor in converting electrical power into mechanical power. By multiplying these three factors together, we can determine the actual power consumed by the motor.

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  • 5. 

    YOU ARE A RMO AND YOU WANT TO WORK ON THE MACHINES PRESSURE RELIEF VALVE ON A DUAL PRESSURE RELIEF VALVE SYSTEM.  WHAT VALVE WOULD YOU INSTALL TO WORK ON ONE PRESSURE RELIEF VALVE WHILE ALLOWING THE OTHER ONE TO OPERATE IN THE SYSTEM?

    • GATE VALVE

    • BUTTERFLY VALVE OR PLUG VALVE

    • TWO WAY VALVE

    • THREE WAY VALVE

    Correct Answer
    A. THREE WAY VALVE
    Explanation
    A three-way valve would be the appropriate choice in this situation because it allows the RMO to work on one pressure relief valve while still allowing the other one to operate in the system. The three-way valve has three ports, which can be used to divert the flow of fluid. By positioning the valve correctly, the RMO can isolate one pressure relief valve from the system while still allowing the other one to function properly. This provides a safe and efficient way to work on the machines' pressure relief valve without disrupting the overall operation of the system.

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  • 6. 

    YOU ARE AN RMO AND YOU START THE MACHINE AND THE MACHINE DOESN'T START.  YOUR FUSES, CIRCUIT BREAKERS AND ELECTRICAL COMPONENTS ARE ALL GOOD.  WHAT WOULD YOU CHECK NEXT?

    • SIGHTGLASS

    • THERMOSTAT

    • LOW PRESSURE CUT OUT, PRESSURE SWITCH

    • REFRIGERANT CHARGE

    Correct Answer
    A. LOW PRESSURE CUT OUT, PRESSURE SWITCH
    Explanation
    If the fuses, circuit breakers, and electrical components are all good, the next thing to check would be the low pressure cut out and pressure switch. These components are responsible for monitoring the pressure in the system and can shut off the machine if the pressure is too low. If these components are faulty or not functioning properly, they could be preventing the machine from starting. Therefore, checking the low pressure cut out and pressure switch would be the logical next step in troubleshooting the issue.

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  • 7. 

    WHAT IS USED TO TRACK SPEED IN A STEAM TURBINE?

    • TACHOMETER

    • SPEEDOMETER

    • PEDOMETER

    • TRACKOMETER

    Correct Answer
    A. TACHOMETER
    Explanation
    A tachometer is used to track speed in a steam turbine. A tachometer is a device that measures the rotational speed of a shaft or disk. In the context of a steam turbine, it is used to measure the speed at which the turbine is rotating. This information is important for monitoring and controlling the operation of the turbine, as well as for maintenance and troubleshooting purposes.

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  • 8. 

    YOU ARE USING COPPER TUBING TO REPLACE A PART OF A REFRIGERATION SYSTEM.  WHAT IS USED TO BEND THE TUBING? 

    • PIPE HICKEY

    • SPRING TYPE TUBE BENDER

    • VISE

    • PINCH BAR

    Correct Answer
    A. SPRING TYPE TUBE BENDER
    Explanation
    A spring type tube bender is used to bend the copper tubing in a refrigeration system. This tool is specifically designed to create smooth and accurate bends in tubing without causing any damage or kinks. It uses a spring mechanism to provide the necessary leverage and control for bending the tubing to the desired shape. Using a spring type tube bender ensures that the tubing maintains its structural integrity and allows for proper flow of refrigerant through the system.

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  • 9. 

    WHY IS GLYCOL A BETTER BRINE THAN SODIUM CHLORIDE?

    • MORE CONDUCTIVE

    • COST LESS

    • NO CORROSION

    • HIGHER FREEZING POINT

    Correct Answer
    A. NO CORROSION
    Explanation
    Glycol is a better brine than sodium chloride because it does not cause corrosion. This means that when glycol is used as a brine, it does not damage or deteriorate the equipment or pipes it comes into contact with. In contrast, sodium chloride can cause corrosion over time, leading to potential damage and maintenance costs. Therefore, glycol is a preferable option as a brine due to its non-corrosive properties.

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  • 10. 

    WHICH OF THE FOLLOWING ELECTRICAL COMPONENTS HAVE THE ABILITY TO STORE ELECTRICITY AND ARE SOMETIMES USED TO START MOTORS?

    • RESISTOR

    • RECTIFIER

    • GENERATOR

    • CAPACITOR

    Correct Answer
    A. CAPACITOR
    Explanation
    A capacitor is an electrical component that has the ability to store electric charge. It consists of two conductive plates separated by an insulating material known as a dielectric. When a voltage is applied across the plates, one plate accumulates positive charge while the other accumulates negative charge. This stored charge can be discharged rapidly when needed, making capacitors useful for starting motors. When a motor is started, a large amount of current is required, and capacitors can provide this initial surge of electricity. Therefore, capacitors are the correct answer to the question.

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  • 11. 

    WHAT INFORMATION MUST BE STAMPED ON A FUSIBLE PLUG?

    • TYPE OF REFRIGERANT IT CAN BE USED WITH

    • MELTING POINT OF ALLOY

    • RELEASE PRESSURE

    • RESET PRESSURE

    Correct Answer
    A. MELTING POINT OF ALLOY
    Explanation
    The information that must be stamped on a fusible plug is the melting point of the alloy. This is important because the melting point determines at what temperature the plug will melt and release the pressure in the system. By knowing the melting point, technicians can ensure that the plug is compatible with the operating conditions and will function properly in case of excessive pressure buildup.

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  • 12. 

    WHY CAN'T YOU USE A FLARE FITTING 3/4" OR LARGER?

    • CAN'T FLARE THAT LARGE

    • CAN'T TIGHTEN TO GET A GOOD SEAL

    • AGAINST THE LAW

    • EASIER TO SWEAT

    Correct Answer
    A. CAN'T TIGHTEN TO GET A GOOD SEAL
    Explanation
    A flare fitting that is 3/4" or larger cannot be used because it cannot be tightened enough to create a good seal. Flare fittings rely on the compression of the flare against the fitting to create a tight seal, and larger flare fittings may not be able to achieve this level of compression. Therefore, it is easier and more effective to use a different method, such as sweating or soldering, for larger fittings.

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  • 13. 

    WHEN WATER TURNS TO ICE, WHAT TAKES PLACE?

    • SUPERHEAT

    • HEAT OF FUSION

    • HEAT OF EVAPORATION

    • SUBCOOLING

    Correct Answer
    A. HEAT OF FUSION
    Explanation
    When water turns to ice, heat energy is released from the water and transferred to the surroundings. This process is known as the heat of fusion. The heat of fusion is the amount of energy required to change a substance from a liquid to a solid state at its melting point. In the case of water, this is the energy released when it freezes and forms ice.

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  • 14. 

    WHAT IS THE TOTAL MAXIMUM AMOUNT OF REFRIGERANT YOU CAN STORE IN THE MACHINERY ROOM APART FROM YOUR REFRIGERANT IN YOUR MACHINE?

    • 100 LBS

    • 150 LBS

    • 300 LBS

    • 5 DRUMS

    Correct Answer
    A. 300 LBS
    Explanation
    The total maximum amount of refrigerant that can be stored in the machinery room, apart from the refrigerant in the machine, is 300 lbs. This means that any additional refrigerant stored in the machinery room cannot exceed this weight limit.

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  • 15. 

    AN OPEN TYPE COMPRESSOR IS KEEPING THE REFRIGERANT FROM ESCAPING BY TIGHTENING A SEAL MADE OF:

    • RUBBER

    • GRAPHITE LOADED FIBER

    • CARBON AND METAL

    • FORTIFIED PLASTIC

    Correct Answer
    A. CARBON AND METAL
    Explanation
    An open type compressor is keeping the refrigerant from escaping by tightening a seal made of carbon and metal. Carbon and metal are both strong materials that can withstand the pressure and temperature fluctuations in a compressor. They provide a tight and secure seal to prevent any leakage of the refrigerant.

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  • 16. 

    AFTER LEAK DETECTING WITH MOISTURE OF NITROGEN AND A TRACE OF R-22, THE RMO:

    • HAS TO RECOVER ONLY THE R-22

    • CAN VENT THE MIXTURE TO THE ATMOSPHERE

    • RECOVER BOTH INTO THE SAME CONTAINER

    • RECOVER BOTH, BUT IN SEPARATE CYLINDERS

    Correct Answer
    A. CAN VENT THE MIXTURE TO THE ATMOSPHERE
    Explanation
    The correct answer is "CAN VENT THE MIXTURE TO THE ATMOSPHERE." This means that after leak detecting with moisture of nitrogen and a trace of R-22, the RMO is allowed to release the mixture of nitrogen and R-22 into the atmosphere. This suggests that the mixture is not considered harmful or hazardous, and it is acceptable to vent it into the surrounding environment.

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  • 17. 

    ON A CENTRIFUGAL WATER PUMP THE CONDITIONS ARE CORRECTLY PRIMED WHEN:

    • IT IS FULL OF WATER AND ALL AIR HAS BEEN PURGED OUT

    • WATER IS LEAKING FROM THE PACKING

    • THE PACKING WILL MAINTAIN THE WATER IN THE PUMP

    • NO REFRIGERANT IS LEAKING

    Correct Answer
    A. IT IS FULL OF WATER AND ALL AIR HAS BEEN PURGED OUT
    Explanation
    The correct answer is that the pump is full of water and all air has been purged out. This is because for a centrifugal water pump to function properly, it needs to be completely filled with water and any air trapped inside needs to be removed. Air pockets can cause cavitation and reduce the pump's efficiency. Therefore, the conditions are correctly primed when the pump is full of water and all air has been purged out.

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  • 18. 

    IF YOU HAVE A 3 LINE CABLE SUPPLYING ENERGY TO YOUR EQUIPMENT, AND ONLY TWO LINES HAVE FUSES, THE UNFUSED LINE WOULD BE?

    • CONNECT THE EXTRA LINE TO MAKE 3 PHASE

    • 2 UNFUSED WIRES DO NOT NEED TO BE INSULATED

    • THE NEUTRAL LINE OF A 120/240 CIRCUIT

    • THIS WOULD PRESENT AN UNSAFE CONDITION

    Correct Answer
    A. THE NEUTRAL LINE OF A 120/240 CIRCUIT
    Explanation
    The correct answer is THE NEUTRAL LINE OF A 120/240 CIRCUIT. In a 120/240 circuit, there are three lines: two hot lines and one neutral line. The neutral line is not fused because it carries the return current from the equipment back to the power source. Fusing the neutral line would disrupt the flow of current and could cause an unsafe condition. Therefore, in a 3-line cable with only two fused lines, the unfused line would be the neutral line.

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  • 19. 

    A RECIPROCATING COMPRESSOR SHAFT SEAL IS MADE UP OF:

    • PLASTIC

    • RUBBER

    • GRAPHITE FIBER HEMP

    • METAL

    Correct Answer
    A. METAL
    Explanation
    A reciprocating compressor shaft seal is made up of metal because metal seals are known for their durability, strength, and ability to withstand high pressures and temperatures. Metal seals also provide a tight and reliable seal, preventing any leakage of the compressed gas. Additionally, metal seals are resistant to wear and tear, making them suitable for the reciprocating motion of the compressor shaft.

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  • 20. 

    LIQUID LEVEL GAUGES (EXCEPT BULL'S EYE TYPE) SHALL HAVE SHUT OFF VALVES:

    • MANUAL ONLY

    • AUTOMATIC ONLY

    • VALVES NOT NEEDED

    • MANUAL AND AUTOMATIC

    Correct Answer
    A. MANUAL AND AUTOMATIC
    Explanation
    Liquid level gauges (except bull's eye type) should have shut off valves that can be operated manually and automatically. This means that the shut off valves can be closed manually by an operator and can also be closed automatically in case of any emergency or abnormal conditions. Having both manual and automatic shut off valves ensures that the liquid level can be controlled and the flow can be stopped promptly when required, providing safety and control in the operation of the liquid level gauges.

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  • 21. 

    WHAT IS A SUPERHEATED VAPOR?

    • VERY HIGH TEMPERATURE GAS MIXED WITH LIQUID

    • DRY VAPOR

    • DRY VAPOR AT ITS BOILING POINT

    • DRY VAPOR ABOVE ITS BOILING POINT

    Correct Answer
    A. DRY VAPOR ABOVE ITS BOILING POINT
    Explanation
    A superheated vapor refers to a vapor that is in a gaseous state and is at a temperature higher than its boiling point. In other words, it is a dry vapor that has been heated beyond the point where it would normally condense into a liquid. This can occur when heat is added to a vapor without increasing its pressure, causing the temperature to rise above the boiling point.

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  • 22. 

    IF 10 BTUs IS TRANSFERRED TO 10 LBS. OF WATER, THE INCREASE IN TEMPERATURE IS CLOSEST TO:

    • 10°F

    • 10°C

    • 1°F

    • 1°C

    Correct Answer
    A. 1°F
    Explanation
    When 10 BTUs of heat is transferred to 10 lbs. of water, the increase in temperature is closest to 1°F. This is because the specific heat capacity of water is 1 BTU/lb°F, which means that it takes 1 BTU of heat to raise the temperature of 1 lb. of water by 1°F. Therefore, when 10 BTUs of heat is transferred to 10 lbs. of water, the temperature will increase by 1°F.

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  • 23. 

    WHEN YOU ARE FINISHED LEAK TESTING WITH NITROGEN AND R-22, THEN THE NEXT STEP WOULD BE:

    • VENT REFRIGERANT AND NITROGEN TO OPEN AIR

    • REMOVE REFRIGERANT AND NITROGEN AT RECOVERY MACHINE

    • ADD REFRIGERANT

    • ADD REFRIGERANT IF NEEDED AND PUT SYSTEM BACK ONLINE

    Correct Answer
    A. VENT REFRIGERANT AND NITROGEN TO OPEN AIR
  • 24. 

    WHAT IS THE MAIN DISADVANTAGE OF THE SUCTION LINE FILTER DRIER COMPARED TO THE LIQUID LINE FILTER DRIER?

    • SUCTION LINE FILTER DRIER IS HARDER TO CHANGE THAN THE LIQUID LINE FILTER DRIER

    • IS LESS EFFICIENT THAN THE LIQUID LINE FILTER DRIER DUE TO DENSITY OF REFRIGERANT

    • SUCTION LINE FILTER DRIER IS TOO BIG AND BULKY

    • IF IT GETS CLOGGED THE SUCTION LINE FILTER DRIER REDUCES MORE OF THE CAPACITY OF THE COMPRESSOR THAN THE LIQUID LINE FILTER DRIER

    Correct Answer
    A. IF IT GETS CLOGGED THE SUCTION LINE FILTER DRIER REDUCES MORE OF THE CAPACITY OF THE COMPRESSOR THAN THE LIQUID LINE FILTER DRIER
    Explanation
    The main disadvantage of the suction line filter drier compared to the liquid line filter drier is that if it gets clogged, the suction line filter drier reduces more of the capacity of the compressor than the liquid line filter drier.

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  • 25. 

    WHAT WOULD BEST DESCRIBE THE REFRIGERANT IN THE LAST EVAPORATOR COIL?

    • VAPOR

    • SATURATED VAPOR

    • SUPERHEATED VAPOR

    • DRY VAPOR

    Correct Answer
    A. SUPERHEATED VAPOR
    Explanation
    The refrigerant in the last evaporator coil would be best described as superheated vapor. Superheated vapor refers to a state where the refrigerant has absorbed additional heat energy beyond its saturation point, resulting in a higher temperature than the boiling point at a given pressure. This means that the refrigerant has transitioned from a saturated vapor state to a superheated vapor state, which is important for efficient heat transfer in the refrigeration cycle.

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  • 26. 

    1000 BTUs OF HEAT IS ADDED TO 100 LBS. OF WATER.  HOW MANY DEGREES DID THE TEMPERATURE OF WATER INCREASE?

    • 10°C

    • 10°F

    • 1°C

    • 1°F

    Correct Answer
    A. 10°F
    Explanation
    When 1000 BTUs of heat is added to 100 lbs. of water, the temperature of the water increases by 10°F.

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  • 27. 

    WHEN A THERMOSTATIC EXPANSION VALVE IS OPERATING PROPERLY, THE END OF THE COIL WILL CONTAIN

    • SATURATED VAPOR

    • SUPERHEATED VAPOR

    • LOW TEMPERATURE LIQUID

    • HOT VAPOR

    Correct Answer
    A. SUPERHEATED VAPOR
    Explanation
    When a thermostatic expansion valve is operating properly, the end of the coil will contain superheated vapor. This is because the expansion valve is designed to regulate the flow of refrigerant into the evaporator coil. As the high-pressure liquid refrigerant passes through the expansion valve, it undergoes a phase change and turns into a mixture of saturated liquid and vapor. The saturated liquid further evaporates inside the coil, absorbing heat from the surroundings and becoming superheated vapor. Therefore, the correct answer is superheated vapor.

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  • 28. 

    TO RAISE 10 LBS. OF WATER 1°F, HOW ANY BTUs DO YOU NEED?

    • 1

    • 5

    • 20

    • 10

    Correct Answer
    A. 10
    Explanation
    To raise 10 lbs. of water by 1°F, you would need 10 BTUs. The BTU (British Thermal Unit) is a unit of energy commonly used to measure the heat energy required to raise the temperature of water. In this case, since the question specifies the amount of water (10 lbs.) and the temperature increase (1°F), the answer is simply 10 BTUs.

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  • 29. 

    THE CENTER PORT OF THE GAUGE MANIFOLD IS CONNECTED TO?

    • RECOVERY MACHINE

    • CHARGING CYLINDER

    • VACUUM PUMP

    • ALL OF THE ABOVE

    Correct Answer
    A. ALL OF THE ABOVE
    Explanation
    The center port of the gauge manifold is connected to all of the above options, which include the recovery machine, charging cylinder, and vacuum pump. This means that the center port serves as a connection point for these different components, allowing for the transfer of gases or fluids between them.

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  • 30. 

    HOW LONG DOES IT TAKE TO WARM UP A STEAM TURBINE?

    • 15-20 MINUTES

    • 30-40 MINUTES

    • NO LESS THAN 60 MINUTES

    • DOESN'T NEED WARM UP

    Correct Answer
    A. 15-20 MINUTES
    Explanation
    A steam turbine takes approximately 15-20 minutes to warm up. This is because the turbine needs to reach its optimal operating temperature before it can efficiently generate power. During the warm-up period, the turbine gradually increases in temperature to ensure that all components expand uniformly and reduce the risk of thermal stress. Once the turbine reaches the desired temperature, it is ready to operate at its full capacity.

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  • 31. 

    ON A VALVE PLATE, WHERE ARE THE SUCTION AND DISCHARGE VALVES LOCATED?

    • SUCTION ON TOP, DISCHARGE ON BOTTOM

    • SUCTION ON BOTTOM, DISCHARGE ON TOP

    • SUCTION AND DISCHARGE ON TOP

    • SUCTION AND DISCHARGE ON BOTTOM

    Correct Answer
    A. SUCTION ON BOTTOM, DISCHARGE ON TOP
    Explanation
    On a valve plate, the suction and discharge valves are located with the suction valve on the bottom and the discharge valve on the top.

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  • 32. 

    IF YOU NEED TO ADD ANOTHER PUMP ONLINE, HOW DO YOU DO IT?

    • OPEN SUCTION SIDE VALVE AND PUT DISCHARGE IN THE THROTTLE POSITION

    • OPEN SUCTION, CLOSE DISCHARGE

    • CLOSE SUCTION, OPEN DISCHARGE

    • OPEN SUCTION AND SLOWLY FULLY OPEN DISCHARGE

    Correct Answer
    A. OPEN SUCTION SIDE VALVE AND PUT DISCHARGE IN THE THROTTLE POSITION
  • 33. 

    THE PUMP SEAL PREVENTS WATER FROM LEAKING ON A CENTRIFUGAL WATER PUMP WHEN UNDER POSITIVE PRESSURE.  WHAT OTHER FUNCTION MAY IT HAVE?

    • TO ALLOW WATER TO LEAK OFF WHEN USING MECHANICAL SEAL TYPE

    • SHOWS THAT WATER IS INSIDE WHEN IT IS DRIPPING

    • PREVENTS AIR FROM ENTERING WHEN IT IS UNDER NEGATIVE PRESSURE

    • STEAM CREATES POSITIVE PRESSURE TO PREVENT STEAM LEAKAGE

    Correct Answer
    A. PREVENTS AIR FROM ENTERING WHEN IT IS UNDER NEGATIVE PRESSURE
    Explanation
    The pump seal prevents air from entering when it is under negative pressure.

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  • 34. 

    BEFORE USING A VOLTMETER, THE TECHNICIAN SHOULD ALWAYS:

    • ZERO THE OHM ADJUSTMENT

    • TOUCH THE TWO LEADS TOGETHER TO ENSURE CONTINUITY

    • SET THE RANGE SELECTOR TO A SETTING HIGHER THAN THE VOLTAGE EXPECTED TO BE READ

    • TURN THE POWER OFF

    • NONE OF THE ABOVE

    Correct Answer
    A. SET THE RANGE SELECTOR TO A SETTING HIGHER THAN THE VOLTAGE EXPECTED TO BE READ
    Explanation
    The technician should always set the range selector to a setting higher than the voltage expected to be read before using a voltmeter. This is because if the range selector is set too low, it may not be able to accurately measure the voltage and could potentially damage the voltmeter. By setting the range selector higher, the technician ensures that the voltmeter can handle the voltage being measured and provides a more accurate reading.

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  • 35. 

    WHAT TYPE OF BEARING IS USED FOR TURBINE ROTOR SHAFT?

    • NEEDLE BEARING

    • SLEEVE BEARING

    • BALL BEARING

    • KINGSBURY BEARING

    Correct Answer
    A. KINGSBURY BEARING
    Explanation
    A Kingsbury bearing is used for the turbine rotor shaft. Kingsbury bearings are commonly used in high-speed rotating machinery, such as turbines, where they provide excellent support and stability. These bearings consist of multiple pads or shoes that are arranged in a circular pattern around the shaft. The pads are lubricated and allow for smooth rotation of the shaft, even at high speeds. Kingsbury bearings are designed to handle heavy loads and provide reliable operation in demanding applications, making them suitable for use in turbine rotor shafts.

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  • 36. 

    A HALIDE TORCH IS TO BE USED OUTSIDE ON A ROOFTOP TO CHECK FOR LEAKS ON A REFRIGERATION UNIT.  WHY SHOULD YOU NOT GENERALLY USE THIS DEVICE OUTSIDE?

    • RAIN CAN GET IN AND AFFECT ITS PERFORMANCE

    • WIND CAN AFFECT THE FLAME SIZE

    • YOU WILL NOT BE ABLE TO DETECT THE CHANGE IN COLOR DUE TO THE BRIGHTNESS OUTSIDE

    • OXYGEN OUTSIDE MAY CAUSE EXPLOSION

    Correct Answer
    A. YOU WILL NOT BE ABLE TO DETECT THE CHANGE IN COLOR DUE TO THE BRIGHTNESS OUTSIDE
    Explanation
    Using a halide torch outside on a rooftop to check for leaks on a refrigeration unit may not be effective because the brightness outside can make it difficult to detect the change in color that indicates a leak. The halide torch relies on a change in color to identify leaks, but if it is too bright outside, the color change may not be easily visible. Therefore, it is generally not recommended to use this device outside for leak detection purposes.

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  • 37. 

    WHAT IS THE ORDER OF COMPONENTS ON THE LIQUID LINE OF A RECIPROCATING SYSTEM FROM THE KING VALVE?

    • FILTER DRIER, SOLENOID VALVE, SIGHT GLASS, TEV TO EVAPORATOR

    • SOLENOID VALVE, FILTER DRIER, SIGHT GLASS, TEV TO EVAPORATOR

    • SIGHT GLASS, SOLENOID VALVE, FILTER DRIER, TEV TO EVAPORATOR

    • TEV, SIGHT GLASS, SOLENOID VALVE, FILTER DRIER TO EVAPORATOR

    Correct Answer
    A. FILTER DRIER, SOLENOID VALVE, SIGHT GLASS, TEV TO EVAPORATOR
    Explanation
    The correct order of components on the liquid line of a reciprocating system from the king valve is filter drier, solenoid valve, sight glass, TEV to evaporator. This order ensures that the refrigerant passes through the filter drier first to remove any contaminants, then through the solenoid valve to control the flow of refrigerant, followed by the sight glass to provide a visual indication of the refrigerant's condition, and finally through the TEV (Thermal Expansion Valve) to regulate the flow of refrigerant into the evaporator.

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  • 38. 

    THE RMO WANTS TO GET A TEMPERATURE READING FROM THE SUCTION LINE, BUT THERE ARE NO GAUGES:

    • THE RMO CAN TOUCH THE LINE AND USE HIS EXPERIENCE TO ESTIMATE WHAT THE TEMPERATURE IS

    • BUY A THERMOMETER AND STICK IT ON THE SUCTION LINE WITH PUTTY

    • GET TWO THERMOMETERS AND GET THE AVERAGE READINGS

    • TOUCH THE THERMOMETER ON THE SUCTION LINE AND GET A READING

    Correct Answer
    A. BUY A THERMOMETER AND STICK IT ON THE SUCTION LINE WITH PUTTY
    Explanation
    The best explanation for the given correct answer is that buying a thermometer and sticking it on the suction line with putty is the most accurate and reliable method to get a temperature reading. This method ensures that the thermometer is directly in contact with the suction line, providing an accurate measurement. Touching the line and using experience to estimate the temperature may not be as precise, and getting average readings from two thermometers may introduce additional variability.

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  • 39. 

    WHAT IS THE AUXILIARY OIL PUMP USED FOR?

    • STARTING UP

    • LUBRICATING THE MAIN PUMP BEARINGS

    • ONLY USED WHEN MAIN PUMP IS MALFUCTIONING

    • USED IN RECPRROCATING MACHINES

    Correct Answer
    A. STARTING UP
    Explanation
    The auxiliary oil pump is used for starting up the machine. It helps to provide the initial lubrication to the main pump bearings before the main pump takes over. This ensures that the bearings are properly lubricated and protected during the startup process.

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  • 40. 

    WHAT IS THE PURPOSE OF THE GLAND STEAM?

    • CREATE POSITIVE PRESSURE

    • ELIMINATE LEAKAGE AT THE END OF THE SHAFT

    • TO HEAT THE GLANDS

    • BOTH A AND B ARE CORRECT

    Correct Answer
    A. BOTH A AND B ARE CORRECT
    Explanation
    The purpose of the gland steam is to create positive pressure and eliminate leakage at the end of the shaft. Both options A and B are correct because the gland steam serves both functions. It creates positive pressure to prevent any external contaminants from entering the system and eliminates leakage at the end of the shaft to ensure a tight seal.

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  • 41. 

    IF REFRIGERANT OIL IS MEASURED TO HAVE A VISCOSITY AND THE VISCOSITY NUMBER IS LOW, WHAT DOES THAT MEAN?

    • DOESN'T FLOW

    • FLOWS EASILY, SMOOTHLY

    • FLOW IS SLOW

    • RESTRICTED FLOW

    Correct Answer
    A. FLOWS EASILY, SMOOTHLY
    Explanation
    If the refrigerant oil is measured to have a low viscosity number, it means that the oil flows easily and smoothly. Viscosity is a measure of a fluid's resistance to flow, so a low viscosity indicates that the oil has a thin consistency and can move easily. This is beneficial for the refrigeration system as it allows for smooth and efficient circulation of the oil, ensuring proper lubrication and cooling.

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  • 42. 

    WHEN OIL LEAVES THE SUMP IN A CENTRIFUGAL REFRIGERATION SYSTEM, WHERE DOES THE OIL GO?

    • TRAVELS WITH THE REFRIGERANT TO COOL THE REFRIGERATION SYSTEM

    • TRAVELS BACK TO THE OIL SUMP

    • IS COMPATIBLE WITH REFRIGERANT AND WILL TRAVEL THROUGH SYSTEM AND RETURN TO THE OIL SUMP

    • TRAVELS THROUGH THE SYSTEM AND IS DRAINED OUT OF THE SUMP BY A PETCOCK VALVE

    Correct Answer
    A. TRAVELS BACK TO THE OIL SUMP
    Explanation
    When oil leaves the sump in a centrifugal refrigeration system, it travels back to the oil sump. This means that the oil circulates within the system and returns to its original location.

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  • 43. 

    WHEN IS A CENTRIFUGAL WATER PUMP CONSIDERED A "LIFT PUMP"?

    • WHEN THE SUCTION INLET OF THE WATER SOURCE IS BELOW THE PUMP LEVEL

    • WHEN THE DISCHARGE IS 120' ABOVE

    • WHEN THE WATER IS LIFTED BY PUMP

    • WHEN THE PUMP WEIGHS LESS THAN 50 LBS.

    Correct Answer
    A. WHEN THE SUCTION INLET OF THE WATER SOURCE IS BELOW THE PUMP LEVEL
    Explanation
    A centrifugal water pump is considered a "lift pump" when the suction inlet of the water source is below the pump level. This means that the pump is able to lift water from a lower source to a higher discharge point. In this scenario, the pump is primarily responsible for creating the necessary suction force to draw water from the lower source and push it to a higher point.

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  • 44. 

    CENTRIFUGAL COMPRESSORS USE WHAT KIND OF REFRIGERANT?

    • CFCs

    • HIGH PRESSURE REFRIGERANT

    • LOW PRESSURE REFRIGERANT

    • ALL THE ABOVE

    Correct Answer
    A. ALL THE ABOVE
    Explanation
    Centrifugal compressors can use all of the above refrigerants, including CFCs, high-pressure refrigerants, and low-pressure refrigerants. The choice of refrigerant depends on various factors such as the specific application, desired performance, environmental regulations, and safety considerations.

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  • 45. 

    WATER WHEN MIXED WITH REFRIGERANT IN A RECIPROCATING SYSTEM WILL:

    • LUBRICATE THE SYSTEM

    • FORM ACIDS AND SLUDGE

    • CAUSE NON-CONDENSEABLES TO FORM

    • FREEZE UP IN CONDENSER

    Correct Answer
    A. FORM ACIDS AND SLUDGE
    Explanation
    When water is mixed with refrigerant in a reciprocating system, it can react with the refrigerant and other substances present in the system to form acids and sludge. This can be detrimental to the system as it can lead to corrosion, clogging of components, and reduced efficiency. Therefore, it is important to prevent water from entering the system and ensure proper maintenance to avoid the formation of acids and sludge.

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  • 46. 

    QUICK CONNECT FITTINGS ARE CONSIDERED AS:

    • LOW LOSS FITTINGS

    • SOLDERED FITTINGS

    • FLARE FITTINGS

    • AUTOMATIC LOSS FITTINGS

    Correct Answer
    A. LOW LOSS FITTINGS
    Explanation
    Quick connect fittings are considered as low loss fittings because they provide a tight and secure connection, minimizing the loss of fluid or gas during transfer. These fittings are designed to create a leak-free seal, reducing the chances of any leakage or wastage. They are commonly used in industries where efficiency and minimal loss are crucial, such as in plumbing, automotive, and hydraulic systems. The term "low loss" refers to the minimal loss of fluid or gas, making quick connect fittings an ideal choice for applications that require a reliable and efficient connection.

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  • 47. 

    WHAT IS THE PRESSURE OF R-22 AT 41°F?

    • 38 PSIG

    • 70 PSIG

    • 18.5" Hg

    • 81

    Correct Answer
    A. 70 PSIG
    Explanation
    The pressure of R-22 at 41°F is 70 PSIG. This indicates that the refrigerant R-22 is at a pressure of 70 pounds per square inch gauge at a temperature of 41°F.

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  • 48. 

    WHAT IS THE REASON TO PUT TWO LOW SIDE FLOATS IN PARALLEL?

    • YOU CAN MAKE A REPAIR WITHOUT INTERRUPTING THE OTHER

    • EACH ONE FEEDS ITS OWN EVAPORATOR

    • IF ONE CLOGS, FLOW WILL CONTINUE THROUGH THE SECOND

    • WHEN THE LOAD DECREASES IT WILL FEED FASTER

    Correct Answer
    A. EACH ONE FEEDS ITS OWN EVAPORATOR
    Explanation
    The reason to put two low side floats in parallel is that each one feeds its own evaporator. This means that if one of the floats clogs, the flow of refrigerant will continue through the second float, ensuring that both evaporators are still being supplied with refrigerant. Additionally, when the load decreases, the second float will feed faster, helping to maintain proper refrigerant flow and cooling capacity.

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  • 49. 

    WHICH IS BEST TO USE WHEN SOLDERING COPPER, IRON OR STEEL?

    • BRAZING ALLOYS

    • ANY LOW TEMPERATURE SOLDER

    • 50-50 TIN LEAD

    • SILVER SOLDER

    Correct Answer
    A. SILVER SOLDER
    Explanation
    Silver solder is the best option to use when soldering copper. It has a lower melting point compared to other soldering materials, making it easier to work with. Additionally, silver solder provides a strong and durable bond between copper surfaces, ensuring a reliable connection.

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Quiz Review Timeline (Updated): Jul 5, 2024 +

Our quizzes are rigorously reviewed, monitored and continuously updated by our expert board to maintain accuracy, relevance, and timeliness.

  • Current Version
  • Jul 05, 2024
    Quiz Edited by
    ProProfs Editorial Team
  • Feb 10, 2014
    Quiz Created by
    Catherine Halcomb
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