Examen HVAC: HVAC Exam Questions, 2018 - PDF

WRITTEN EXAM 1. The efficiency of the refrigerant cycle is affected by the operation of the condenser. Of the following, a more efficient centrifugal compressor operation results from: A. Raising the condenser liquid level to the maximum B. Lowering the chilled water set point C. Rising the condens...

WRITTEN EXAM 1. The efficiency of the refrigerant cycle is affected by the operation of the condenser. Of the following, a more efficient centrifugal compressor operation results from: A. Raising the condenser liquid level to the maximum B. Lowering the chilled water set point C. Rising the condenser head pressure D. Lowering the condensing pressure 2. The heat removed from the refrigerant in a condenser is: A. Sensible and latent heat B. Latent heat only C. Radiant heat only D. Sensible heat only 3. The refrigerant unit that you have been assigned to is being taken out of service for a major repair. You have been assigned to withdraw refrigerant for storage in suitable containers. According to the New York City fire code, you must ensure that the containers: A. Do not weigh more than 200 pounds when filled B. Are approved by the US Department of Transportation C. Are approved by the OSHA Association D. Do not exceed 55 Gallon in capacity 4. Which of the following best describes how the cylinder unloader works? A. Keep in the suction valve opened while the compressor is in the return stroke B. Controls the clearance volume in the compressor with a solenoid C. Controls the opening of the passage into the compressor with variable vanes D. Unloads the piston to create less pressure 5. In most semi Hermetic compressors, the suction vapor is used to: A. Removes oil from the motor housing B. Cools the motor C. Minimizes oil foaming D. Removes oil foam from the shaft 6. The amount of refrigerant that flows through the orifices of a economizer is determined by the: A. Number of economizer stages B. Temperature of the high side refrigerant C. Number of compressor stages d. Difference between the high side and low side pressure 9/19/18 7. The installation of an inline refrigerant cleaning system is advisable: A. For high pressure refrigerant systems B. To purge non-condensables C. For systems using toxic refrigerant D.To remove impurities from the system 8. The type of refrigerant system that is least likely to leak refrigerant into the building space that are being cooled: A. The direct vented closed system B. The direct closed system C. Any system using reciprocating compressor D. The indirect system 9. The suction pressure of a reciprocating compressor is 65 PSIG. The discharge pressure of this compressor is 120 PSIG. The atmospheric is 14.7 PSI. The compression ratio for the given condition is closest to: A. 2. 0 7 C.1. 6 9 B. 4.41 D. 1.84 10. A Superheated vapor is a: A. Dry vapor at the saturation temperature B. Dry saturated vapor C. Dry vapor above the saturation temperature D. Vapor with minimal amount of included liquid 11. A refrigerante engineer verifies that a condenser water pump is cavitating. Of the following the most likely cause for this condition is: A. A Faulty cooling tower water level controller B. Operating at sustaining high loads C. Too long a period between pump servicing D. Refrigerant leaks through the pumps packing 12. A Centrifugal water pump is known as a lift pump when the: A. The pump lifts the water into the pump upon startup B. the water supply to the pump suction inlet is below the pump level C. Thedischargeheadexceed150feet D. Thepumpisstartedwiththesuctionvalveopen 13. A TXV is used to maintain constant: A. Refrigerant flow B. Evaporator pressure C. Evaporator pressure drop D. Evaporator superheat 14. The chilled water supply to the building is 55F. if the chiller is being used for human comfort, should you be concerned about this, and why? A. Yes, this temperature is too low for human comfort purpose B. Yes, this temperature is too high for human comfort purpose C. No, 55F is within an acceptable range D. No, temperature gauges often give false high readings 15. The packing gland of a centrifugal pump serves to: A. Keep the bearing cooled B. Keeps air out of the pumps when the impeller housing is under negative pressure C. The drip part of the packing gland gives evidence that there is water in the pump D. Al of the answers are correct 16. Capacity control of a reciprocating hermetic compressor is typically achieved through A. Regulating the opening of the discharge valve B. Variation of the condenser water temperature C. Regulating the opening of the TXV D. Operation of the hot gas bypass valve 17. The most important reason to sub-cool the refrigerant in the condenser is to ensure that: A. A Pure liquid refrigerant will enter the metering device B. Liquid slugs will not enter the compressor C. The condenser is working efficiently D. The cooling tower has sufficient water 18. A Refrigeration engineer is logging reading from a reciprocating system. compressor discharge temperature have dropped significantly and the suction line pressure si high. which of the following that may be causing this set of condition. A. Compressor cycle B. An expansion valve that is open to wide C. Malfunction of a unloader D. Anexpansionvalvethatisclosedtomuch 19.A low side float valve is used to maintain: A. A constant refrigerant flow B. The water level in the cooling towers C. The level of refrigerant in the condenser D. The level of the refrigerant in the evaporator 20. Regarding fire safety, which ASHRAE refrigerant safety classification indicates no flammability and lower toxicity? A.A3 B.A1 C.B1 D.B2 21. When an expansion valve is operating properly, at the end of the evaporator will contain: A. Saturated liquid refrigerant B. Only liquid refrigerant C. Only vapor D. Only superheated vapor 22. What information is not contained in a Material Safety Data Sheet-MSDS? A. Health and physical hazards of the material B. Safety work practice and required protective equipment of the material C. Procedures that should be followed in case of an emergency D.Costo of the material 23. In a steam turbine, what is the function of the Kingsbury thrust bearing A. Maintain axial positioning of the rotor shaft B. Maintain first stage steam pressure C. Compensate for coupling misalignment D. Adjust shaft torque at start up 24. A Centrifugal water pump is considered to be fully primed when A. The pump is full of air B. Liquid or leaking past the packing gland C. The pump runs with no knocking noise D. The pump is full of liquid 25. Copper tubing refrigerant lines must be installed for a new system. it is a well known service practice that tubing collapses at bends that must be made, the refrigerant engineer should use A. Brazed elbows B. Annealed tubing C. Lever type tubing bender D. Avery small bend radius 26. A reciprocating compressor is making a knocking sound during operation. If the refrigerant worn parts are not causing the knocking, what is probably the cause A. Misalignment of the compressor motor B.The slugging of the liquid refrigerant C. Parallel misalignment of the compressor and motor D. Insufficient lubrication 27. In order for a refrigerant to become superheated it must be heated in a section of the low side refrigerant line: A. Where the medium being cooled is hottest B. Where refrigerant pressure is lowest C. Where no liquid refrigerant is present D. That is outside the evaporator 28. Al liquid has been recovered from a system to be overhauled, the system A. Should not be opened until al vapor has been recovered B. Should have air pumped through it and vented to atmosphere before being opened C. Should be pumped with dry nitrogen before being opened D. Can be safety opened and repaired 29. When a refrigerant engineer uses a portable compressor recovery unit to remove vapor refrigerant from a refrigeration system the removal rate of the refrigerant will gradually slow down because A. The vapor density is decreasing B. The refrigerant temperature is dropping C. The speed decreasing D. The compressor efficiency is decreasing 30. You are the engineer running a 2000-ton (steam-driven turbine) centrifugal refrigeration system, a refrigeration system supplies chilled water to a college campus with multiple buildings. During the course of making your rounds, you check the 9 cell cooling tower on the roof. You note the the water level in all of the cooling tower cells is very low. Which one of the following immediate actions would take? A. Gradually lower the chiller water set point on the refrigerant system. B. Add additional make up water to cooling tower C. Create a deeper vacuum pressure in the surface condenser and turn on a second condensate pump D. Drastically increase the speed of the cooling tower 31. A rooftop water cooling tower is connected to a water pump in the building basement with a 12 inches diameter pipe. With the pump turned off, a pressure gauge at the pump's inlet shows a pressure of 140 PSIG the height of the water column, in feet, would be closest to. A.277. B.375 C,323 D.190 32. What device protects the steam turbine from excessive speed? A. Governor assembly B. Maximum speed set point control C. High steam flow cutout D. Double seat globe valve 33. A refrigeration compressor has failed to turn on. The refrigeration engineer on duty verifies that the electrical circuit to the motor, including al switches and circuit breakers, si complete according to recommended service practice, the next item to be checked would likely be the: A. Temperature and pressure controls B. Liquid line solenoid valve C Refrigerant charge D. Cooling tower operation 34. Refrigerants are characterized by their physical properties included flashpoint, refrigeration effect, and others. Of the refrigerants in commercial and industrial the highest latent heat and refrigerant effect is: A. R-12 B. Ammonia C. R-22 D. Propane 35. On what characteristics is ASHRAE refrigerant safety group classification system: A. Explosives and toxicity B. Explosives and flammability C. Flammability and toxicity D. Acidity and explosiveness 36. Of the following, and example of an in-line refrigerant cleaning system that may be used with a centrifugal compressor containing R123 refrigerant is: A.Refrigerant recycling B. Refrigerant recovery C. Refrigerant reclaiming D. Refrigerant disposal 37. Information about the physical and chemical properties of a hazardous material can be found in: A. New York Medical code B. Manufactures Safety Directions Sheet C. Material Safety Data Sheet D. New York City Fire Code 38. What is the function of the turbine auxiliary oil pump? A. Check proper oil level in pump before start up B. Stand by pump if main pump fails C. Recovers oil from the condensate tank D. Establish oil pressure during turbine start up 39. The rupture disc for a low-pressure centrifugal refrigeration machine is normally located on the: A. Compressor suction B. Condenser C. Compressor discharge D. TXV 40. What is the primary reason ribbed metal piping is used for electrical wires connected to the refrigeration system shown below? A. It is easier to install than non- ribbed metal piping B. It allows for flexibility and accounts for vibrations C. Itallowsforventilatingtheheatfromwires D. It is less costly to use than non- ribbed metal piping 41. Multi- cylinder reciprocating compressors uses cylinder unloaders to regulate capacity, what would not occur if some of the unloaders fail to operate when needed? A. The chill water temperature will increase B. The chilled water temperature will decrease C. The evaporator temperature will be lowered D. The discharge pressure will increase 42. As shown in the picture below, the suction gauge of a condenser water pump reads 55 PSI. The pipe supplying the pump is 75 feet long and 12 inches in diameter. approximately how many gallons of water do you expect to obtain if this pipe is drained completely? A.8478 B.236 C.59 D.440 43. Awater chiller system uses refrigerant R123. Aleak in the evaporator shell mat result in A. Ahigher than normal high side pressure B. The formation of ice around the point of leakage C. Low pressure shut-down D. Setting of the refrigerant monitor alarm 44. Capacitors are used on refrigeration motors. Of the following, the function of these devices is to? A. Act as inductive devices to cause the motor current ot lag the voltage. B. Store electrical charges during starting and running the motor C. Convert electrical to magnetic and then to mechanical energy D. Defrost refrigerant cooled motors 45. Of the following, centrifugal refrigerant machine is best characterized by: A. Low and high operating pressure B. High volume low pressure machine C. Use of refrigerant for direct cooling of the occupied space D. The use of air-cooled condenser 46. Which of the following ASHRAE refrigerant safety classification is the most flammable? A. A1 B. B1 C. B2 D.АЗ 47. Which of the following correctly describes the object in the picture below? A. Water chemistry supply station, for condenser water B. Cooling tower water makeup valve, to add water to the tower C. Standpipe hose outlet, to put out fires in case of emergency D. Carbon dioxide system nozzle, to extinguish electrical fires 48. Modern compressors usually seal the rotating shaft as it exits the compressor housing a spring loaded seal made of A. Rubber B. Low friction plastic C. Metal or carbon D. Graphite loaded fiber 49. The British Thermal Unit (BTU) is the measurement of heat of energy. fI 10 BTU are transferred to 10 pounds of water, the water temperature increase will be ciosest to: A. 10F B. 1C C.1F D.10C 50. A reciprocating compressor cylinder has a 10 inches bore and 14 inches stroke. The volume of refrigerant, in cubic inches, will be closer to: A. 1808 B. 1406 C. 1099 D. 1002 51. An electrically operated control requires 24 volts to operate. to change the available 110 volts to 24 volts A. Rectifier B. Step- down capacitor C. Low temperature wire D. transformer 52. In an indirect refrigeration system, of the following, the one that would not be used as a cooling medium for the building spaces being cooled is: A. Acalcium chloride solution B. A sodium chloride solution C. R22 refrigerant D. Glycol 53. On a steam turbine, what would cause the atmospheric valve to open? A. Low vacuum in the surface condenser B. Leaking tubes in the surface condenser C. All answer are correct D. Dirtytubesinthesurfacecondenser 54. You are the engineer running a 2000-ton (steam-driven turbine) centrifugal refrigeration system, a refrigeration system supplies chilled water to a college campus with multiple buildings. making your rounds, you notice that condenser water pump#1 is making a lot of noise, the discharger gauge reading of the condenser water pump is fluctuating drastically, and motor of the condenser pump #1 is running very hot. Which of the following actions would you take: A. Turn on pump #2, shut of pump#1, and trouble shot pump #1 B. Gradually increase the chilled water set point from 40F to 46F, so the machine can cool down C. Leave pump #1 running, but immediately put in a call to the service contractor D. Gradually turn on the water make-up pump to add water to the chilled water loop 55. Electric devices may be used to provide built in defrosting of refrigeration machine evaporator units. These devices are classified as A. Induction coils B. Thermostats C. Capacitors D. Resistors 56. The flash point of compressor lubricating oil: A. Should be higher than the compression temperature B. Is the temperature at which the oil start to foam C. Is the temperature at which the viscosity is measured D. Should be lower than the compression temperature 57. The primary way of achieving capacity control of a centrifugal compressor is by; A. Variation in steam pressure B. Adjustment of the impeller inlet pre-rotation vanes C. Operation of the hot gas bypass valve D. Adjustment of the thermal expansion valve 58. Cooling tower water requires the addition of chemical additives in order to: A. Lower head pressure B. Regulate and maintain the PH level C. Reduce the formation of scale and algae D. Comply with E.P.A. regulation 59. In the picture below describe the equipment's function? A. Relieve excess pressure from the evaporator B. Control flow of refrigerant to the compressor C. Remove non condensable from the condenser D. Relieve excess pressure from the condenser 60. The viscosity of lubrication oil is described by a number. Alow viscosity number describes oil that: A. Flows easily B. Should not be used with refrigerant C. Flows poorly D. Does not provide good lubrication 61. The most likely reason for a refrigeration engineer to use a psychrometer is to measure A. Atmosphere pressure B.Relative humidity level of the atmosphere C. Temperature of the atmosphere D. Undesired substance in the atmosphere 62. The most important reason to use at least two compressors in a cascade system is to: A. Accomplish higher temperature B. Avoid very high compression ratio for each compressor C. Avoid the need for water -cooled condenser D. Divide the cooling load between the compressors 63. The suction service valve of a reciprocating compressor is front seated and the compressor runs until the low pressure cut-out shut the compressor off. When the machine is stopped, the refrigeration engineer notices that the suction pressure increase rapidly. The most probable cause of this pressure rise: A. Afaulty gauge B. A leaking suction service valve C. Al answers are correct D. Malfunction of a compressor valve 64. Regarding the functioning of a steam turbine, why is it advisable to keep moisture in the iniet low as possible? A. Decrease vacuum leaks B. Decrease turbine warm up time C. Keeps turbine blades wear to minimum D. Keeps steam traps from rusting 65. According to the attached Material Safety Data Sheet (MSDS) R134 is a A. Dark blue liquid B. Clear, odorless liquid and vapor C. Yellow gas that smells like rotten eggs D. Light blue liquid 66. Under normal condition, the refrigerant enters the compressor as a: A. Low pressure vapor and leaves as a high pressure saturated vapor B. Low pressure superheated vapor and leaves as a high pressure vapor C. Low pressure superheated vapor and leaves as a high pressure saturated liquid D. High temperature vapor and leaves as a low pressure vapor 67. While operating an R-22 single acting compressor system, the refrigeration engineer noticed oil foaming in the crankcase. This condition most likely, would have been caused by a: A. Sudden drop in the crankcase pressure B. High oil temperature C. Moisture in the oil D. Addition of liquid Freon 68. Assume that an engineer is able to observe refrigerant water and oil together. The fluids would settle in the container from top to bottom: A. Water, oil, refrigerant B. Oil, refrigerant, water C. Refrigerant, oil, water D. Oil, water, refrigerant 69. What is the function of the vacuum breaker in a steam turbine. A.To achieve a faster coast down cycle B. To keep main bearing oil from foaming C. To keep vacuum at proper level D. To indicate presence of vacuum leak 70. An equalizer line on a TXV is used to: A. Eliminate the pressure across the evaporator B. Compensate for the pressure drop across the evaporator coil C. Equalize the pressure across the TXV diaphragm or bellow D. Correct for pressure drop in the thermal bulb capillary lines 71. If R134 accidentally touches a refrigerant engineer's skin, what first aid should be applied from the MSDS? A. R134 is a low acute toxicity, no special medical attention is required B. Promptly flush skin with water until al chemical is removed C. Rub the frozen parts D.The frostbite parts in hot water (above 130F) to warm them up 72.In a multi stage centrifugal compressor, each stage: A.Has higher tip speed than one before it B. Handles more refrigerant than the one before ti C. sI identical in volume to the other stages D. Has smaller volume than the one before it 73. A refrigeration engineer notices excessive cycling of the temperature control for a reciprocating compressor refrigeration unit. The crankcase temperature is high, the compressor discharge temperature low, the suction line temperature is high. of the following the one that may causing this set of condition. A. An expansion valve that is open too wide B. The purge unit operation C. The condenser operation, dirty tubes or cooling control D. Faulty compressor valves 74. On an operating centrifugal compressor refrigerant unit, the refrigeration engineer notices that the compressor is short cycling. The unit is using low side float valve as a metering device. of the following requirements this would indicate that: A. Inspection should be made for a dirty and partially plugged discharge line B. The system is undercharged with refrigerant C. The compressor wiring be inspected D. The system is over charged with refrigerant 75. The vessel depicted below may used in connection with A. Refrigerant recovery B. Refrigerant recycling C Refrigerant reclaiming D. Refrigerant disposal 76. Arefrigeration system uses jet ejector to raise settled oil mixed with refrigerant to the oil pump. If a restriction in the refrigerant flow to the jet ejector develops: A. The flow of oil will be unaffected B. The temperature of the refrigerant exiting the jet will decrease C. The oil will not lift ti is mixed with less refrigerant D. There may be insufficient head to lift the oil 77. An indirect low temperature refrigerant system frequently uses glycol, instead of salt brine, as the intermediate cooling medium. an advantage of this choice is: A. The elimination of corrosion B. High flow rate C. Better thermal conduction D. Lowcost 78. In relation to the suction pressure of a compressor, the reading on the oil pressure gauge should read in the range, closer to: A. 15 to 30 PSI higher B. 15 to 30 PSI lower C. 30 to 60 PSI lower D. 60 to 80 PSI Higher 79. Non- condensable gases like air, oil vapor, or nitrogen travel through a refrigerant system with the refrigerant they usually accumulate in the: A. Condenser B. Compressor crankcase C. Filter drier D. Evaporator 80. The advantage of forced draft cooling tower over natural draft cooling towers is: A. Smaller tower size B. That it uses less water C. That it improves power efficiency in water tower D. Reduced energy cost 81. The sole refrigeration engineer on duty in a building is permitted to leave the building refrigeration system when it is in operation only when: A. Lunch or dinner occur B. System is an automatic operation C. Relieved by another licensed refrigeration engineer D. The assistant provides coverage or supervision 82. Asystem controlled by a TXV show high discharge pressure and high normal sub-cooling. The cause is most probably a: A. Superheat settings that has been set incorrectly B. Refrigerant overcharge C. Leaking compressor discharge valve D. Low system amperage draw 83. Which of following is a correct statement? A. 2.5 gallon of water weight 10.7 pounds B. 2.5 Gallon of water weight 1.05 pounds C. 2.5gallons of water weighs 20.8 pounds D. 2.5 gallons of water 2.5 cubic feet. 84. Liquid level gauge glasses (except the bull's eye) are generally equipped with: A. Manual and automatic closing shut off valves. B. Manual shut-off valves only C. Automatic shut-off valves only D. Eithermanualorautomaticclosingshut-offvalves 85. Copper and aluminum are frequently used for condenser tubes in refrigeration system these metals are used because of their: A. Easy availability B. High heat transfer coefficient C Resistance to corrosion D. Resistance to failing 86. Assume that a refrigeration engineer has a choice of four valves to select from. Which of the following is the most effective type of valve to control pressure? A. Ball valve B. Quarter turn valve C. Gate valve D.Plug valve 87. Where must the Material Safety Data Sheets be located? A. Near the entrance to the machine room B. Where flammable liquids are used C. Where available D. Where any toxic material is used 88. The oil collected ni an oil separator is generally: A. Drained and replaced with fresh oil B. Filtered and returned to the compressor C.Caused by oil overcharge D. Returned to the compressor 89. What is the function of gland steam? A. Preventfoaminginoilpump B. Heat the bearing oil before start up C. Seal the turbine rotor carbon rings D. Heat the diaphragm carbon rings before start up 90. Regarding the functioning of steam turbine, how is the water level controlled in the surface condenser hot well? A. Change of the speed of the turbine B. Operation of the recirculation and overboard valves C. Reduction the turbine steam pressure D. Variation of the condenser water flow 91. The cause of a starved evaporator might be: A. High refrigerant charge B. High condenser water temperature C. Superheat that is to low D. Low refrigerant charge 92. A refrigeration engineer is running two centrifugal condenser water pumps in parallel. One of the pumps is at maximum pumping rate. If by mistake, the refrigeration engineer throttles back on the discharge valve of the other pump, the most likely effect wil be: A. A reduction on the total flow rate to the condenser B. Areduction in the water pressure at the condenser inlet C. A reduction in both the water flow rate and pressure into the condenser D. For the pumps components to maintain both the flow rate and discharge pressure 93. The total amount of heat to be removed from the refrigerant in a condenser equals the heat picked up in the: A. Evaporator plus the heat of compression B. Evaporator plus the heat of included non-condensable C. Evaporator less the heat given up in the muffler D. Evaporator 94. The amount of electrical power used to operate a solenoid valve or a motor is measured in: A. Ohms B. Amperes C.Volts D. Foot pounds 95. Of the following, the most common metering device used today in reciprocating commercial refrigeration system under three tons capacity is: A. Automatic expansion valve B. Orifice plate C. Low side float system D. TEV 96. The purpose of wear rings in a centrifugal pump is to: A. Minimum water leakages around the shaft B. Center the impeller in the pump casing C. Prevent wearing of the pump housing and impeller D. Act as a bearing to reduce axial motion after wears occurs 97. You are the engineer running a 2000-ton (steam-driven turbine) centrifugal refrigeration system, a refrigeration system supplies chilled water to a college campus with multiple buildings. While making rounds, you notice that the condenser water coming back down from the 9-cell cooling tower on the roof is at a temperature of 90F. You want to make a adjustment to bring the temperature of the condenser water down to 85F. Which one of the following immediate actions would you take? A. Increase the speed of the cooling tower fans B. Lower the chilled water set point on the refrigeration system to 85F C. Add additional make-up water to the cooling tower D. Put on a second chilled water pump 98. Awater chiller is equipped with a reciprocating compressor, a thermostatic expansion valve and an air cooled condenser. Arestriction in the refrigerant liquid line would result in: A. Low condenser pressure B. High amperage draw C. High pressure cutout actuation D. High suction superheat 99. Asolenoid valve is used to allow a reciprocating refrigeration machine to adapt to the load on the system. The opening of the solenoid valve is caused by: A. Spring action which is driven by the pressure is created in a thermal bulb B. The action of an ac relay using a polsat relay C. Counterweight creating pressure D. An electrical current creating a magnetic field 100. The process by which refrigerant is extracted and cleaned for reuse without requirements for reclamation is called A. Reclaim B. Recover C. Repair D.Recycle 101. Acentrifugal compressor is in operation with suction pressure is 3 psig and the discharge is 10 psi what is the atmospheric pressure is 14.7 which is the ratio closet to: A. 2.31 B. 2.35 C.1.39 D. 0.89 102. You are the engineer running a 2000 ton (steam-driven turbine) centrifugal refrigeration system, a refrigeration system supplies chilled water to a college campus with multiple buildings. The panel display on the refrigeration system indicates that the problem is water flow. What do you do? A. Check the condenser water pump and restart the refrigeration system. B. Decrease the chilled water set point, and restart the refrigeration system C. Leave the refrigeration system off for 2 hours before attempted a restart D. Call in service contractor 103. Electrical current is measured in? A. Voltage B. Resistance C. Amperage D. Impedance 104. How would you put an additional pump online? A. Open suction valve, open discharge valve gradually B. Open suction valve, close discharge valve C Close suction valve, open discharge valve D. Open suction valve and slowly close discharge valve 105. Of the following, the major advantage of a shell and coil condenser is: A. Itiseasiertocleanwithoutdisturbingtherefrigerantconnection B. There is less dangers of developing leaks C. Has higher heat transfer coefficient D. Better level liquid control all the condenser may be activated 106. An engineer needs to vary the flow of refrigerant in a refrigeration system. Which operation in the fiow of the system does not include: A. Solenoid valve B. Low side float C. Highsidefloat D. Tev 107. Thermal bulb is attached to the suction pipe between the evaporator coil and the compressor by an insulated line. Assume that the machinery room is at 85F. break down of the insulation results in: A. Starve evaporator B. Excessive super heat C. Adequate super heat D. Flood the evaporator 108. Achill water system uses refrigerant R134 a leak in the evaporator shell may result in: A. Set off the refrigerant monitor alarm B. Higher than normal high side pressure C. The foam of ice around the point of leak D. Low pressure shut down 109. What are steam ejector used for on the surface condenser of a system with a turbine: A. To regulate turbine speed: B. To increase the surface area of the condenser C. To create aproper operating exhaust vacuum D. To remove steam condensate from the condenser 110. Water and moisture is serious problem in a refrigerant system how to avoid: A. Use of fins in refrigerant line B. Proper evacuation at the charging of the system C. Proper handling of refrigerant and oil to avoid exposure to mixture D. Use of high viscosity oil in the connection 111. The most important requirements for a good evaporator is that: A. Ari or liquid refrigerant can be used as required by the medium being cooled B. It must have enough cooling surface to absorb the required heat. C. Operates only when the heat load exceeds a minimum D. The refrigerant is contained in tubes 112. While on duty a refrigeration engineer notice that the suction line to the compressor and part of the compressor itself is frosted of the following, the most likely reason for this condition would be: A. Low condenser water temperature B. The TEV is almost close C. There Is a blockage in the liquid line D. There si not enough refrigerant ni the system 113. While doing a routine line inspection, the engineer notices the bulb of the TXV on the floor refrigerant engineer should attach bulb at the: A. Threequarterswaytowardstheendofthecoil. B. The inlet end of the coil C. The expansion valve outlet D. The outlet end of the coil 114 To conver water at 32F to ice at the same temperature a refrigeration must remove: A. Latent heat of vaporization B. The heat of crystallization C. Sensibility heat D. The latent heat of fusion 115. The use of oil ni the refrigeration machine is to: A. Mix the oil with liquid refrigerant B. Add non condensables to refrigerant C. Reduce wear and friction ni the compressor parts D. None of the above 116. The following si a desirable property ni a refrigeration A. High corresponding operation pressure B. High viscosity C. High latent heat D. High corresponding compressor discharge temperature 17. The cooling medium for an evaporative condenser is: A. Air B. Air and water C. Water D. Condenser fan 118. The ratio of the actual pressure of water vapor in the atmosphere to the saturated pressure of give temperature is: A. Partial pressure B. Humidly affect C. Absolute humidity D. Relative humidity 119. The only refrigerant /temperature chart available to a refrigerant engineer list the temperature is degrees Celsius fi the chart indicates a Celsius temperature of 4 degrees to equivalent to F: A.35.2 degrees B.39.2 degrees C.27.0 degrees D.18.4 degrees 120. Arefrigerant engineers was instructed to charge of 60 ton plant with R134A Refrigerant. The refrigerant engineer will most likely find the charging valve on the A. Discharge side of the compressor B. Receiver C. High side pressure side of the system D. Low pressure side of the system 121. Arefrigerant engineer verifies that achilled water pump si cavitating. Of the following the most likely cause for this condition is: A. A faulty cooling tower water level controller B. Operating at sustaining high loads C. Too long a period between pump servicing D. Water leaks through the mechanical seals 122. There is a decrease in the efficiency of a reciprocating compressor. This mostly likely caused by: A. High suction pressure B. Leaking suction valve C. Low suction pressure D. Leaking discharge line 123. The suction and discharge valve of the reciprocating compressor are mounted as follows: A. Suction and discharge valve on the upper side of the plate B. Suction and discharge valve below the valve plate C. Discharge valves below the valve plate and suction valve above it D. Discharge valve on top of the valve plate and suction valve below. 124. You are the engineer running a 2000 ton (steam-driven turbine) centrifugal refrigeration system, a refrigeration system supplies chilled water to a college campus with multiple buildings. While making your rounds you notice that the discharge pressure of your condenser water pumps is significantly lower than the normal. Which following action would you avoid taking: A. Put on a addition condenser water pump B. Flush out the bucket strainer of the condenser water pump. C. Send you assistant to check for cooling tower level D. Put on an additional surface condenser pump and lower the chiled water set point. 125. Awater pump is discharge against head 92 feet of water, this is approximately to a pressure of: A. 95 psi B. 20 psi C.40 psi D. 180.psi 126. Which one of the following will connect to the middle port on a gauge manifold? A. Solenoid valve B. King valve C. Vacuum pump D. Suction or discharge service valves 127. The most important reason for installing a muffler in reciprocating refrigerant machine is: A. Prevent compressor damage B. Prevent condenser damage C. To contain the compressor pulsation noise D. To reduce velocity of the refrigerant 128. Of the following, the statement that most accurately characterize a hermetic compressor is that it: A. Typically has a pressure lubrication system B. Will have only the motor enclosed in a gas tight housing C.Will have both the compressor and motor enclosed is gas tight housing D. Is erected in the field 129. In the picture the valve is in what position: A. The valve is closed B. The valve position cannot be determined. VALUE HANLE AT A 4 5 C. The valve is cracked open D. The valve is fully opened 130. What si the order of components on the liquid line of a reciprocating system from the condenser to the TEV? A. Filter drier, solenoid valve, king valve, sight glass B. King valve, filter drier, solenoid valve, sight glass. C Sight glass, solenoid valve, filter drier, king valve D. Filter drier, solenoid valve, sight glass, king valve 131. Ahigh-side float valve is used to maintain: A. Constant level of refrigerant in the evaporator B. Constant rate of refrigerant flow C. Constant flow of condenser water D. Constant level of refrigerant in condenser 132. Picture of a pump: A. Ninety degree reducing elbow, pump suction, pump casing, pump discharge, check valve B. Forty five degree reducing elbow, pump suction, motor housing, pump discharge, check valve C. Forty five degree straight elbow, pump suction, pump casing, pump discharge, vibration reducer D. Ninety degree reducing elbow, pump discharge, pump casing, pump suction, vibration reducer 133. Picture of a compressor: A. Oil drain connection, allows for the removal of oil from the compressor only B. Refrigerant charging port, allows for the addition and remove of refrigerant from the compressor C. Oil ctharging port allows for the addition and removal of oil from the compressor D. Oil charging port, alows for the addition of oil from the compressor, only 134. Afacility has failed to maintain water treatment to a refrigerant system: A. Clogging of the cooling tower B. Increase in the condenser pressure C. Corrosion of the cooling tower metals D. Cavitation of condense water pumps 135. Which of these compressors is not a positive displacement type compressor? A. Rotary B. Screw C. Reciprocating D. Centrifugal 136. Where is emergency power not required according to code? A. Egress illumination B. Data centers C. Fire Pumps D. High rise elevators 137. What is the most widely used regulation book by operating engineers is? A. OSHA B. EPA C. BOMA D. NFPA 138. What type of refrigerant do you need FDNY approval for? A. Ammonia B. R-22 C. Propane D. R-134A 139. Centrifugal pressure is determined by? A. Speed of motor B. Variable guide vanes C. Design speed D. Electrical voltage 140. Asingle phase 208 VAC circuit has 2 hot wires the third is the? A. Spare wire B. Ground C. Control wire D. Common 141. Liquid refrigerant that has passed through a metering device is a? A. High pressure liquid B. Sub cooled liquid C. Low pressure saturated liquid D. ILow pressure vapor 142. With a 75degree dry bulb and a 73degree wet bulb the relative humidity is? A. Normal B. Very low C. 100% relative humidity D. Very high 143. After recovering liquid refrigerant from a centrifugal chiller the next step is to? A. Blow the system out with nitrogen B. Pull a deep vacuum C. Recover vapor D. Leak test system 144. Where is the muffler located? A. Between the compressor and condenser B. Between the evaporator and condenser C. After the condenser D. Before the compressor 145. What is not required to be serviced annually? A. Fire extinguishers B. Fire pump motors C. Compressors D. Diesel engine systems 146. What is the advantage of a sheil and tube condenser, as opposed to a shell and coil condenser? A. Easier to clean B. Prevents less leaks C. Better heat transfer D. Less efficient 147. Fusible plugs on a condenser: A. Release refrigerant by pressure B. The melting point is marked on it C. Can be back seated D. Are not allowed by code 148. How much extra refrigerant can be stored in a machine room? A. 20% above the normal charge B. 220 lbs. C. The amount equal to the design pressure D. 30 Ibs. 149. What is used on an outside pipe to prevent it from freezing? A. Capacitor B. Resistor C. Heater coil D. Transformer 150. Of the following centrifugal chillers are best characterized as? A. High tonnage, low pressure machines B. Low tonnage, high pressure machine. C High tonnage, high pressure machine D. Low tonnage, low pressure machine 151. As an engineer you notice pressure drops across the evaporator. You check and notice the external equalizer line is disconnected. What will occur in the evaporator? A. Evaporator wil flood B. Evaporator will starve C. Evaporator will stabilize D. Evaporator will be unaffected 152. When entering Phase Il fireman's service, what statement is correct? A. Does not need a special key B. Can only be used by a firefighter C. The elevator operator is the only person that could control the elevator D. Must be tested semi-annually 153. AFDNY permit is required to conduct hot works for? A. Brazing B. Welding C. Use of oxygen and flammable gas D. Al of the above 154. FDNY is most concerned with which ASHRAE refrigerant classification? A. Al B. B2 С. АЗ D. B1 155. How long must a Fire alarm log book be kept? A. 5years B. 1year from last entry C. 6months D. 3years 156. What is the minimum requirement an engineer needs to log readings? A. Every2hours B. Once per shift C. Every hour D. E v e r y 4 h o u r s 157. You are the only engineer on duty with a machine running. Avice president tells you to shovel snow. What should you do? A. Cal your union rep B. Shovel snow C) Do not leave building D. Shovel but check the machine regularly 158. How often must you do emergency power testing? A. Weekly B. Bi-weekly C. Annually D. Monthly 159. What is the responsibility of a B29 COF holder? A. Maintain the battery system B. Test the battery system C. Inspect the battery system D. Repair minor problems 160. Why is a refrigerant gauge called a compound gauge? A. You can read the pressure on the high side and the low side B. Youcanreadtemperatureandpressure C. It has scales for different types of refrigerant D. It reads positive pressure and vacuum 161. Which of the following does not require flame resistant treatment? A. Decorations in a hotel lobby B. Decorations in a building lobby C. Art work in a museum D. Aheavycurtaininatheater 162. An engineer observes a gauge that reads saturation pressure of a refrigerant. If chilled water is circulate as the cooling medium this reading best be used to estimate the? A. Chilled water return from building spaces being pumped to the spaces beincooled B , Temperature of chilled water being pumped to the spaces being cooled C. Pressure of chilled water being pumped to spaces that are being cooled. D. Cooling tower efficiency. 163. Regardless of the ASHRAE refrigerant classification in use, in the event of a refrigerant escape the engineer should be aware of? A. Refrigerant fire B. Refrigeranttoxicity C. Asphyxiation D. Refrigeration odor 164. What type of refrigerant is found inside the machines gauges? A. R-134A B. Same type of refrigerant inside the machine C. R-22 D. Glycol 165. If resistance is cut in half, what happens to the power factor? A. Gets cut by half B. Increases by a factor of two C. Decreases by a factor of two D. Increased by half 166. What are pre hot works procedures performed prior to hot works? A. Check area once a day leading up to hot works B. Check area one week prior to hot works C. Check area day of hot works D. Check area day after hot works 167. Achilled water system has an air cooled condensing unit on a roof during cold weather has what type of protection? A. Glycol running through ti B. Heater coil C. Ari limiting device D. Resistor 168. What is acompressor safety head? A. Apressure relief on the low side B. Cylinder head with a pressure relief on the high side C. Aspring on the valve plate D. Rupture disc 169. Standpipe certificate should be available for? A. FDNY&OSHA B FDNY and building inspector C. FDNYandEPA D. FDNYandNFPA 170. When is a chemical fire extinguisher system needed? A. Where water si not sufficient B. Pre action system C. Deluge system D. High rise office buildings 171. What is most accurate about fire alarm books? A. Must be kept on premises within 1 year from log of last entry B. Must be kept ni the fire alarm panel C. Must be kept ni the building managers office D. Must be kept on the premises no less than five years 172. What is the volume of a box 12"x12"x12" measure? A. 1728 inches B. 1728 square inches C. 1cubic foot D. 144 cubic feet 173. Acondenser pump is supplied with 85 degree water from a cooling tower and returns to the tower at 88 degrees Engineer is sure the condenser tubes are clean and free of obstructions. The condenser has high condenser pressure. The reason for this could be? A. Over charge of refrigerant B. Undercharge of refrigerant C. Thermostat is damaged D. Wide open water regulating valve 174. Fireproof decorations in buildings are useful for? A. Seasonal purposes B. Don't catch fire ni an emergency C. Usually energy efficient D. Help reduce heat load 175. What is the lowest temperature a cooling tower can be? A. Ambient temperature B. Drybulbtemperature C. Wet bulb temperature D. Between dry bulb and wet bulb 176. Manifold hoses should be equipped with? A. Quick disconnects B. Fow loss fittings C. Schrader valves D. Service apertures 177. Water regulating valves are used to? A. Vary flow based on water temperature B. Maintain refrigerant temperature C. Maintain condenser pressure to a pre-determined level D. Maintain low side pressure to proper level 178. What type of sprinkler system needs inspecting? A.Automatic B. Non-automatic C. Residential D. Commercial, hotel& office buildings 179. You are performing hot works near a sprinkler head. What can you do to prevent the fire alarm from going off? A. Take the building offline B. Drain the sprinkler system in that area C.Put a non-combustible barrier to protect the sprinkler head D. Perform hot works in service area 180. How long does it take to warm up a steam turbine? A 10-15 minutes B. 30-40 minutes C. No less than 60 minutes D. Doesn't need warm-up 181. Why is a pressure relief valve better that a fusible plug? A. Less costly B. Minimizes refrigerant loss C. Can be tested D. Adjustable 182. What is the state of refrigerant entering the compressor on a reciprocating machine? A. Vapor B. Superheated vapor C. Saturated vapor D. Liquid 183. In the absence of water chemical treatment of a cooling tower? A.Drain the tower every one to two weeks &replace with fresh water B. Punch tubes every week C. Clean condenser pump strainers D. None of the above 184. What is ammonia's refrigerant ASHRAE classification? A. A1 B. B3 C.B2 D. A3 185. What is the function of a safety head on a compressor? A. Capacity control B. Prevents liquid slugging from damaging the valve plate C. Purge air from cylinders D. Prevent friction 186. What does awiring diagram display? A. Wiring of components B. Wiring of switches only. C Switch functions D. Al of the above 187. Filter driers remove A. Air and acids B. Moisture and particles C. Oilandacids D. Moisture and air 188. Show a picture of an insulated pump and ask what is this pump? A. Centrifugal pump B. Reciprocating pump C. Centrifugal chill water pump D. Condenser pump 189. If 29.92" HG is equal to 14.7 Psia then 26" HG converts to what ni Psia? A. 13 B. 30.3 С. 12.77 D. 7.5 190. When charging refrigerant on the low side of a reciprocating machine with manifold gauges, what is the position of the manifold? A. High and low side backseated B. High and low side frontseated C. High side backseated low side frontseated D. High side front seated low side back seated 191. You are the engineer running a 2,000 ton steam driven turbine centrifugal refrigeration system supplying chilled water to a college campus with multiple buildings. You are supplying 46 degree chilled water. Al the buildings are satisfied except one building. What action should the engineer do? A. Put an additional chilled water pump online. B. Lower the set point from 46 degrees to 40 degrees C. Add additional make up water to the cooling tower D. Increase the speed of the cooling tower fans 192. The cooling medium for a cooling tower is? A. Ari B. Water C. Air and water D. Tower fan 193. The charge in a TEV sensing bulb is? A. Non Flammable Non Toxic B. Similar to refrigerant ni system C. Highly toxic highly flammable D. Different type of refrigerant than ni system 194. When you are finished leak testing with R22 and nitrogen the next step would be? A. Vent refrigerant and nitrogen to open air B. Remove refrigerant and nitrogen with recovery tank C. Add refrigerant back into system D. Add refrigerant if needed and put system back online 195. What is the device used to measure the speed of a turbine? A. Governor B. Gimpel valve C. Tachometer D. First stage nozzle gauge 196. The condenser pump is on the first floor and not running. The pressure gauge show 55 psi. There is 15 feet for each floor. What floor is the cooling tower on? A.6 B. 8 C.10 D. 12 197. There is 7.48 gallons per cubic foot. How many gallons of water are in a pipe 8 feet in diameter and 10 feet long? A. 26 B. 80 C.3758 D. 748 198. A technician has been asked to estimate the cost of operating a 5 horse power motor. Because the plant is build by energy consumed as kilowatt-hours, the technician will have to calculate the conversion. The equivalent in energy of a 5 horse power motor operating for 9 hours in kilowatt- hours is closest to: A.33.6 B.4.79 C. 3.73 D. 11.9 199. Astandpipe system wil be out of service for two days. How long should there be a fire watch? A. The first 24 hours B. The entire time the standpipe is out of service C. The first 12 hours in the morning D. The last 12 hours of the day 200. Acircuit breaker has a similar function as what? A. Afuse B. Asolenoid C. Aresistor D. Arelay 201. How do you start a centrifugal chiller? A. Start the chilled water pump, start condenser water pump, start compressor, check oil, start cooling tower B. Start the chilled water pump, start condenser water pump, check oil, start compressor, start cooling tower C. Start cooling tower, check oil, start compressor, start the chilled water pump, start condenser water pump D. Start the chilled water pump, start condenser water pump, check oil, start cooling tower, start compressor 202. fI a sprinkler system si offline for two days how often do you need to inspect it until it is returned back to service? A. Only in the morning not at night until restored B. Only in the evening not the morning until restored C. Continuously 24 hours a day until system is restored D. 12 hours a day until system is restored 203. The only refrigerant/temperature chart available to a refrigerant engineer lists the temperature in degrees Celsius. fI the chart indicates a Celsius temperature of 5 degrees the equivalent in Fahrenheit is? A. 18.4 degrees B. 39.2 degrees C. 41 d e g r e e s D. 27 degrees 204. In the picture below what does the equipment detect? A. Carbon Dioxide B. Oxygen C. Halogen D. Refrigerant leaks 205. In a building with a multizone standpipe system, how does each zone get supplied with water? A. Each zone will be connected to the main water supply B. It wil supply only the highest standpipe zone C. Each zone will have its own automatic water supply D. It will supply only the lowest standpipe zone 206. Which service valve should be installed to isolate a dual pressure relief valve while keeping system in service? A. Two way valve B. Three way valve C. Plug valve D. Stopvalve 207. When will the BTU's exchanged be the greatest? A. High evaporator temperature, low condenser temperature B. High evaporator temperature, high condenser temperature C. Low evaporator temperature, low condenser temperature D. Low evaporator temperature, high condenser temperature 208. You find that the check valve on a centrifugal pump is leaking. When would the most damage be caused to the pump? A. On shutdown of the pump B. On startup of the pump C. When another pump is turned on D. When servicing the pump 209. A motor winding is touching the inside of the motor housing. This could result in: A. Motor would overheat and shut down B. Shock may occur to personnel C. Motor would speed up D. Motor would slow down 210. An engineer suspects a short of the motor windings have caused the motor to trip on overload. The engineer should use what instrument to check the motor: A. Capacitor B. Voltmeter C. Ohmmeter D. Ammeter 211. An engineer would expect a relief valve to start function at a pressure: A. 5% over design pressure B. 20% below design pressure C. Design pressure D. Recommended pressure for normal cooling 212. How many BTU's are removed in a 30 ton system: A. 12,000 BU's per hour B. 360,000 BTUs' per minute C. 12,000 BTUs' per minute D. 360,000 BTUs' per hour 213. An engineer is requested to replace a gauge on the high side of the system. The pressure graduation rate should be: A. At least 1.2 times the design pressure B. Design pressure C. Acompound gauge D. Same as low side pressure 214. An automatic expansion valve maintains a constant: A. Evaporator pressure drop B. Evaporator superheat C. Refrigerant flow D.Evaporator pressure 215. During inspection of a facility you notice that there has been failure to maintain water treatment ofthecondenserwater. Thefirstevidenceofaproblemwouldbe: A. Decrease in superheat temperature entering the compressor B. An increase in compressor head pressure C. An increase in rate of non condensables D. Corrosion of cooling tower metal 216. If the air louvres below the fans in an induced draft cooling tower become clogged the result would be: A. Decrease in make up water supply B. Higher return water temperature C. Lower return water temperature D. A lower condenser approach 217. You have a cold front and there is a sudden drop in temperature. The thermostat will cause the solenoid valve to: Â. Close and pump the compressor down and shut down on low pressure B. Close and the compressor will stop on high pressure C Open and compressor pumps down and goes off on high pressure D. Open and compressor will continue to run at a reduced speed 218. Cross connections and standpipe risers must be painted: A. Green B. Red C Yellow D. Green with yellow stripe 219. Under certain circumstances is it ok to chain an exit door? A. Yes, to keep your building safe from intruders B. Yes, to keep students from leaving school C No, ti si never ok D. Both Aand Bare correct 220. How would you calibrate a thermometer? A. Place the thermometer in a cup of ice water B. Place the thermometer in a cup of hot water C. Place the thermometer in superheated steam D. Compare temperature to another thermometer 221. What device automatically controls the speed of a steam turbine? A.Governor valve B. Gimpel valve C. Sentinel valve D. Main steam valve 222. What happens when a steam turbine reaches critical speed? A. Turbine will shut down B. Turbine will vibrate violently. C Turbine will slow down D. Turbine will sped up