RMO Final Exam Questions and Complete Solutions.

RMO Final Exam Questions and Complete Solutions A standpipe system will 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 D)The last 12 hours of the day - Answer: The entire time the standpipe is out of service. The only refrigerant temperature chart available to a refrigerant engineer lists the temperature in degrees Celsius. If the chart indicates a Celsius temperature of 5 degrees the equivalent in Fahrenheit is A) 18.4 degrees B) 39.2 degrees C) 41 degrees D) 27 degrees - Answer: 41 degrees C = F-32 / 1.8 A technician has been asked to estimate the cost of operating a 5 horsepower motor. Because the plant is build by energy consumed kilowatt - hours, the technician will have to calculate the conversion. The equivalent in energy of a 5 horsepower motor operating 9 hours in kilowatt-hours is closet to. A) 33.6 B) 4.79 C) 3.73 D)11.9 - Answer: 33.6 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 will 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 - Answer: Each zone will have its own automatic water supply 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) Stop valve - Answer: Three way valve 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 - Answer: Low evaporator temperature, high condenser temperature If a sprinkler system is 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 - Answer: Continuously 24 hours a day until system is restored 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 - Answer: Between the compressor and the condenser The most important reason to sub-cool the refrigerant in the condenser is to ensure that 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 - Answer: Pure liquid refrigerant will enter the metering device 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 - Answer: Start the chilled water pump, start condenser water pump, check oil, start cooling tower, start compressor 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 answers are correct D) Dirty tubes in the surface condenser - Answer: All answers are correct A circuit breaker has a similar function as what A) Fuse B) Solenoid C) Resistor D) Relay - Answer: Fuse 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) 2.07 B) 4.41 C) 1.69 D) 1.84 - Answer: 1.69 Regarding fire safety, which ASHRAE refrigerant safety classification indicates no flammability and lower toxicity A) A3 B) A1 C) B1 D) B2 - Answer: B2 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 - Answer: Oil, water, refrigerant A water chiller system uses refrigerant R123. A leak in the evaporator shell may result in A) A higher-than-normal high side pressure B) The formation of ice around the point of leakage C) Low pressure shut down D) Setting off the refrigerant monitor alarm - Answer: A higher-than-normal high side pressure Which of the following best describes how the cylinder unloader works A) Keep in the suction valve opened while the compressor is in 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 - Answer: Keep in the suction valve opened while the compressor is in the return stroke 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 - Answer: The indirect system In the picture below what does the equipment detect A) Carbon Dioxide B) Oxygen C) Halogen D) Refrigerant leaks - Answer: Refrigerant leaks 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 - Answer: 3758 The condenser pump is on the first floor and not running. The pressure gauge shows 55 PSI. There is 15 feet for each floor. What floor is the cooling tower on A) 6 B) 8 C) 10 D) 12 - Answer: 8 What is the device used to measure the speed of the turbine A) Governor B) Gimpel valve C) Tachometer D) First stage nozzle gauge - Answer: Tachometer You are the engineer on duty with a machine running. A vice president tells you to shover snow. What should you do A) Call your union rep B) Shovel snow C) Do not leave building D) Shovel but check the machine regularly - Answer: Do not leave building What is the minimum requirement an engineer needs to log readings A) Every 2 hours B) Once per shift C) Every hour D) Every 4 hours - Answer: Once per shift How long must a fire alarm book be kept A) 5 Years B) 1 Year from last entry C) 6 months D) 3 Years - Answer: 3 Years FDNY is most concerned with which ASHRAE refrigerant classification A) A1 B) B2 C) A3 D) B1 - Answer: A3 CHECK THIS ONE An engineer needs to vary the flow of refrigerant in a refrigeration system. Which operation in the flow of the system does not include A) Solenoid valve B) Low side float C) High side float D) TEV - Answer: Solenoid valve The refrigerant unit that you have been assigned to is being taken out of service. For a major repair. You have been assigned to withdrawal 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 ponds 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 - Answer: Are approved by the US Department of Transportation 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 setpoint C) Raising the condenser head pressure D) Lowering the condensing pressure - Answer: Lowering the condensing head pressure A TXV is used to maintain constant A) Refrigerant flow B) Evaporator pressure C) Evaporator pressure drop D) Evaporator superheat - Answer: Evaporator superheat A refrigerant 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 - Answer: A faulty cooling tower water level controller The ratio of the actual pressure of water vapor in the atmosphere to the saturated pressure of give temperature is A) Partial pressure B) Humidity affect C) Absolute humidity D) Relative humidity - Answer: Relative humidity 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 is not enough refrigerant in the system - Answer: There is not enough refrigerant in the system 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 - Answer: To remove impurities from the system The only refrigerant/temperature chart available to a refrigerant engineer list the temperature in degrees Celsius if 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 - Answer: 39.2 degrees F = C x 1.8 + 32 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 - Answer: To achieve a faster coast down cycle While operating an R-22 single acting compressor system, the refrigeration engineer noticed foaming in the crankcase. This condition most likely, would have been caused by A. A) Sudden drop in Crankcase Pressure B) High oil temperature C) Moisture in the oil D) Addition of liquid Freon - Answer: Sudden drop in crankcase pressure A low side float valve is used to maintain A) Constant refrigerant flow B) Water level in cooling towers C) Level of refrigerant in the condenser D) Level of refrigerant in the evaporator - Answer: Level of the refrigerant in the evaporator 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 - Answer: Low pressure superheated vapor and leaves as a high pressure vapor According to the attached material data safety 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 - Answer: Clear, Odorless liquid and vapor Regarding the function of a steam turbine, why is it advisable to keep moisture in the inlet low as possible A) Decrease Vacuum leaks B) Decrease turbine warm up time C) Keeps turbine blades wear to a minimum D) Keeps steam traps from rusting - Answer: Keeps turbine blades wear to a minimum The most likely reason for a refrigeration engineer to use a Psychrometer is to measure A) Atmospheric pressure B) Relative humidity level of the atmosphere C) Temperature of the atmosphere D) Undesired substance in the atmosphere - Answer: Relative humidity level of the atmosphere Cooling towers 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 regulations - Answer: Reduce the formation of scale and algae The flash point of the 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 - Answer: Should be higher than the compression temperature 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 - Answer: Resistors A water chiller is equipped with a reciprocating compressor, a thermostatic expansion valve and an air cooled condenser. A restriction 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 - Answer: High suction superheat You are the engineer running a 2000-ton (steam-driven turbine) centrifugal refrigeration system, a refrigerantion system supplies chilled water to a college campus with multiple buildings. While making rounds, you notice that the condebser water coming back down from the - Answer: LOOOOOOK UP AND FINISH An engineer suspects a short of the motor winding's 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 - Answer: Ohmmeter A motor winding is touching the inside of the motor housing. This could result in A) Motor would overheat and shutdown B) Shock may occur to personnel C) Motor would speed up D) Motor would slow down - Answer: Shock may occur to personnel 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 - Answer: On startup of the pump Electrical current is measured in A) Voltage B) Resistance C) Amperage D) Impedance - Answer: Amperage 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 - Answer: Open suction valve, open discharge valve gradually The following is a desirable property in a refrigeration A) High corresponding operation pressure B) High viscosity C) High latent heat D) High corresponding compressor discharge temperate - Answer: High latent heat The most important requirements for a good evaporator is that A) Air 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 - Answer: It must have enough cooling surface to absorb the required heat 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 - Answer: Recycle 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 a proper operating exhaust vacuum D) To remove steam condensate from the condenser - Answer: To create a proper exhaust vacuum 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 superheat C) Adequate superheat D) Flood the evaporator - Answer: Flood the evaporator Of the following the major advantage of a shell and coil condenser is A) It is easier to clean without disturbing the refrigeration connection B) There is less dangers of developing leaks C) Has higher heat transfer coefficient D) Better level liquid control all the condenser may be antiquated - Answer: There is less dangers of developing leaks A centrifugal 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 closest too A) 2.31 B) 2.35 C) 1.39 D) 0.89 - Answer: 1.39 The cooling medium for an evaporative condenser is A) Air B) Air and water C) Water D) Condenser fan - Answer: Air and water While doing a routine line inspection, the engineer notices the bulb of the TXV on the floor refrigerant engineer should attach the bulb at the A) Three quarters way towards the end of the coil B) The inlet end of the coil C) The expansion valve outlet D) The outlet end of the coil - Answer: the outlet end of the coil 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 - Answer: Proper evacuation at the charging of the system A chill 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 - Answer: Set off the refrigerant monitor alarm A solenoid 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 any relay using a polstat relay C) Counterweight creating pressure D) An electrical current creating a magnetic field - Answer: An Electrical current creating a magnetic field The suction valve of a reciprocating compressor is front seated and the compressor runs until the low pressure cut-out shuts 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 is A) Faulty gauge B) A leaking suction service valve C) All answers are correct D) Malfunction of a compressor valve - Answer: Malfunction of a compressor valve The heat removed from the refrigerant in a condenser is A) Sensible and latent heat B) Latent heat only C) Radiant heat D) Sensible heat only - Answer: Sensible and latent heat 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 - Answer: Compensate for the pressure drop across the evaporator coil 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) The discharge head exceed 150 feet D) The pump is started with the suction valve open - Answer: The water supply to the pump suction inlet is below pump level 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 - Answer: Low refrigerant charge The oil collected in an oil separator is generally A) Drained and replaced in oil pump B) Filtered and return to the compressor C) Caused by oil overcharge D) Returned to the compressor - Answer: Returned to the compressor What is the function of gland steam A) Prevent foaming in oil pump B) Heat the bearing oil before start up C) Seal the turbine rotor carbon rings D) Heat the diaphragm carbon rings before start up - Answer: Seal the turbine rotor carbon rings Which of the 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) 2.5 gallon of water weighs 20.8 pounds D) 2.5 gallon of water 2.5 cubic feet of water - Answer: 2.5 gallons of water weighs 20.8 A refrigeration 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 if it is mixed with less refrigerant D) There may be insufficient head to lift oil - Answer: There may be insufficient head to lift the oil 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 overcharged with refrigerant - Answer: The system is undercharged with refrigerant Which of the following ASHRAE refrigerant saftey classifactions is the most flammable A) A1 B) B1 C) B2 D) A3 - Answer: A3 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 - Answer: 1099 In a multi stage centrifugal compressor each stage A) Has higher tip speed than the one before it B) Handles more refrigerant than the one before it C) Its identical in volume to the other stages D) Has smaller volume than the one before it - Answer: Is identical in volume to the other stages A refrigeration engineer notices excessive cycling of the temperature control for a reciprocating compressor refrigerant unit. The crankcase temperature is high, the compressor discharge temperature is low, the suction line temperature is high. Of the following the one that may be 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 of cooling control D) Faulty compressor valves - Answer: Faulty compressor valves Of the following, an 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 - Answer: Refrigerant recycling A refrigerant engineer is running two centrifugal water pumps in parallel. One of the pumps is at maximum pumping rate. If by mistake, the refrigeration engineer throttles back on discharge valve of the other pump, the most likely effect will be A) A reduction on the total flow rate to the condenser B) A reduction 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 - Answer: A reduction on the total flow rate to the condenser The total amount of heat 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 - Answer: Evaporator plus the heat of compression 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 - Answer: Adjustment of the impeller inlet pre-rotation vanes 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 - Answer: Plug valve Where must the material safety data sheet be located A) Near the entrance to the machine room B) Where flammable liquids are used C) Where available to all employees D) Where any toxic material is used - Answer: Where available to all employees 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 the pipe is drained completely A) 8478 B) 236 C) 59 D) 440 - Answer: 440 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 - Answer: Establish oil pressure during turbine start up A refrigeration compressor has failed to turn on. The refrigeration engineer on duty verifies that the electrical circuit to the motor, including all switches and circuit breakers is complete according to recommended service practice, the next item to be checked would likely be A) Temperature and pressure controls B) Liquid line solenoid valve C) Refrigerant charge D) Cooling tower operation - Answer: Temperature and pressure controls A system controlled by a TXV show high discharge pressure and high normal sub-cooling. The cause is most probably A) Superheat settings that has been set incorrectly B) Refrigerant overcharge C) Leaking compressor discharge valve D) Low system amperage draw - Answer: Refrigerant overcharge 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 - Answer: Governor assembly Refrigerants are characterized by their physical properties include flashpoint, refrigeration effect and others. Of the refrigerants in commercial and industrial the highest latent head and refrigerant effect is. A) R-12 B) Ammonia C) R-22 D) Propane - Answer: R-22 A refrigeration engineer is logging reading from a reciprocating system. Compressor discharge temperature have dropped significantly and the suction line pressure is high. Which of the following may be causing this set of condition. A) Compressor cycle B) An expansion valve that is wide open C) Malfunction of a unloader D) An expansion valve that is closed to much - Answer: An expansion valve that is wide open 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 - Answer: Condenser The advantage of forced draft cooling tower over natural draft cooling tower is A) Small tower size B) That it uses less water C) That it improves efficiency in water tower D) Reduced energy lost - Answer: Small tower size A multi-cylinder reciprocating compressor uses cylinder unloaders to regulate capacity, what would not occur if some of the unloaders fail to operate when needed A) Chilled water temperature increase B) Chilled water temperature decrease C) The evaporator temperature will be lowered D) The discharge pressure will increase - Answer: Chilled water temperature increases In an indirect system, of the following, the one that would not be used as a cooling medium for the building spaces being cooled is A) Calcium chloride solution B) Sodium chloride solution C) R22 refrigerant D) Glycol - Answer: R22 refrigerant In relation to the suction pressure of a compressor, the reading on the oil pressure gauge should read in the range, close to A) 15 to 30 PSI higher B) 15 to 30 PSI lower C) 30-60 PSI lower D) 60-80 PSI higher - Answer: 15 to 30 PSI higher 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) There may be insufficient head to life the oil - Answer: The elimination of corrosion 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 startup - Answer: Maintain axial positioning of the rotor shaft 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) Cost of the material - Answer: Cost of the material A rooftop water cooling tower is connected to a water pump in the building basement with a 12 inches diameter pipe. with the pump turn off, a pressure gauge at the pumps inlet show a pressure of 140 PSIG the height of the water column, in feet, would be closet to A) 277 B) 375 C) 323 D) 190 - Answer: 323 The packing gland of a centrifugal pump serves to A) Keep the bearing cold 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 there is water in the pump D) All of the answers are correct - Answer: The drip part of the packing gland gives evidence that there is water in the pump 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) Operating of the hot gas bypass valve - Answer: Operating of the hot gas bypass valve 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 - Answer: Design pressure How many BTU's are removed in a 30 ton system A) 12,000 BTU's per hour B) 360,000 BTU's per minute C) 12,00 BTU's per minute D) 360,000 BTU's per hour - Answer: 360,000 BTU's per hour 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) A compound gauge D) Same as low pressure - Answer: At least 1.2 times the design pressure During inspection of a facility you notice that there has been failure to maintain water treatment of the condenser water. The first evidence of a problem would be A) Decrease in superheat temperature entering the compressors B) An increase in compressor head pressure C) An increase in rate of non-condensable D) Corrosion of cooling tower metal - Answer: An increase in compressor head pressure If the air louvers below the fans in an induced draft cooling tower become clogged the result would be A) Decrease in makeup water supply B) Higher return water temperature C) Lower return water temperature D) A lower condenser approach - Answer: Higher return water temperature What device automatically controls the speed of a steam turbine A) Governor valve B) Gimpel valve C) Sentinel valve D) Main steam valve - Answer: Governor valve How often must you do emergency power testing A) Weekly B) Bi-weekly C) Annually D) Monthly - Answer: Monthly 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 - Answer: Inspect the battery system Which of the following does not require flame resistant treatment A) Decorations in a hotel lobby B) Decorations in a building lobby C) Artwork in a museum D) A heavy curtain in a theater - Answer: Artwork in a museum An engineer observes a gauge that reads saturation pressure of a refrigerant. if chilled water is circulated as the cooling medium this reading best be used to estimate the A) Chilled water return from building spaces being pumped to the spaces being cooled 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 - Answer: Temperature of chilled water being pumped to spaces that are being cooled There is a decrease in the efficiency of a reciprocating compressor. The most likely cause A) High suction pressure B) Leaking suction valve C) Low suction pressure D) Leaking discharge line - Answer: Leaking suction valve 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 - Answer: Increases by a factor of two A chilled water system has an air cooled condensing unit on a roof during weather has what type of protection A) Glycol running through it B) Heater coil C) Air limiting device D) Resistor - Answer: Air limiting device What is a compressor safety head A) A pressure relief on the low side B) Cylinder head with a pressure relief on the high side C) A spring on the valve plate D) Rupture disc - Answer: A spring on the valve plate What is the most accurate about fire alarm books A) Must be kept on premises within 1 year from log of last entry B) Must be kept in the fire alarm panel C) Must be kept in the building managers office D) Must be kept on the premises no less than 5 years - Answer: Must be kept in the fire alarm panel What is the volume of a box 12 inches by 12 inches by 12 inches measure A) 1728 inches B) 1728 square inches C) 1 cubic foot D) 144 cubic feet - Answer: 1 cubic foot A condenser 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) Under charge of refrigerant C) Thermostat is damaged D) Wide open water regulating valve - Answer: Over charge of refrigerant Manifold hoses should be equipped with A) Quick disconnects B) Low loss fittings C) Schrader valves D) Service apertures - Answer: Low loss fittings Water regulating valves are used for 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 - Answer: Maintain low side pressure to proper level You have a cold front and there is a sudden drop in temperature. The thermostat will cause the solenoid valve to A) 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 the compressor pumps down and goes off on high pressure D) Open and compressor will continue to run at a reduced speed - Answer: Close and pump the compressor down and shut down on low pressure Centrifugal pressure is determined by A) Speed of motor B) Variable guide vanes C) Design speed D) Electrical voltage - Answer: Speed of motor 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) Low pressure vapor - Answer: Low pressure saturated liquid What is not required to be serviced annually A) Fire extinguishers B) Fire pump motors C) Compressors D) Diesel engine systems - Answer: Compressors What is the advantage of a shell 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 - Answer: Better heat transfer 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) 330 lbs - Answer: 330 lbs Of the following centrifugal chillers are best described as A) High tonnage, low pressure machine B) Low tonnage, high pressure machine C) High tonnage, high pressure machine D) Low tonnage, low pressure machine - Answer: High tonnage, low pressure machine 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 will flood B) Evaporator will starve C) Evaporator will stabilize D) Evaporator will be unaffected - Answer: Evaporator will flood When entering phase II 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 - Answer: The elevator operator is the only person that could control the elevator 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 about it D) Discharge valve on top of the valve plate and suction valve below - Answer: Discharge valve on top of the valve plate and suction valve below An automatic expansion valve maintains a constant A) Evaporator pressure drop B) Evaporator superheat C) Refrigerant flow D) Evaporator pressure - Answer: Evaporator pressure What type of sprinkler system needs inspecting A) Automatic B) Non-automatic C) Residential D) Commercial, hotel and office buildings - Answer: Automatic Why is a pressure relief valve better than a fusible plug A) Less costly B) Minimizes refrigerant loss C) Can be tested D) Adjustable - Answer: Minimizes refrigerant loss A water 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 - Answer: 40 PSI 92 / 2.31 PSI = 40 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 - Answer: Vacuum pump What is ammonia's refrigerant ASHRAE classification A) A1 B) B3 C) B2 D) A3 - Answer: B2 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 - Answer: Ninety degree reducing elbow, pump suction, pump casing, pump discharge, check valve 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 removal of refrigerant from the compressor C) Oil charging port, allows for the addition and removal of oil from the compressor D) Oil charging port, allows for the addition of oil from the compressor, ONLY - Answer: Oil charging port, allows for the addition and removal of oil from the compressor A facility 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 metals D) Cavitation of condenser water pumps - Answer: Increase in the condenser pressure IF 29.92'HG is equal to 14.7 Psia then 26"HG converts to what in Psia A) 13 B) 30.3 C) 12.77 D) 7.5 - Answer: 12.77 Which of these compressors is not a positive displacement type compressor A) Rotary B) Screw C) Reciprocating D) Centrifugal - Answer: Centrifugal Where is emergency power not required according to code A) Egress illumination B) Data centers C) Fire pumps D) High rise elevators - Answer: Data centers What type of refrigerant do you need FDNY approval for A) Ammonia B) R-22 C) Propane D) R-134A - Answer: Propane 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 - Answer: Vent refrigerant and nitrogen to open air The use of oil in the refrigeration machine is to A) Mix the oil with liquid refrigerant B) Add non condensables to refrigerant C) Reduce wear and friction in the compressor parts D) None of the above - Answer: Reduce wear and friction in the compressor parts To convert water 32F to ice at the same temperature a refrigeration system must remove A) Latent heat of vaporization B) The heat of crystallization C) Sensibility heat D) Latent heat of fusion - Answer: Latent heat of fusion 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 compressor - Answer: Avoid very high compression ratio for each compressor All liquid has been recovered from a system to be overhauled, the system A) Should not be opened until all vapor has been recovered B) Should have air pumped through it and vented to atmosphere before being opened C) Should be pumped with nitrogen before being opened D) Can be safely opened and repaired - Answer: Should not be opened until all vapor has been recovered 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 - Answer: Only superheated vapor 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 B) Yes, this temperature is too high for human comfort C) No, 55F is within the acceptable range D) No, the temperature gauges often given false readings - Answer: Yes, this temperature is too high for human comfort 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 - Answer: Relieved by another licensed refrigeration engineer The amount of electrical power used to operate a solenoid valve or a motor measured in A) Ohms B) Amperes C) Volts D) Foot pounds - Answer: Volts Copper and aluminum are frequently used for condenser tubes in refrigeration system, These metals are used because of their A) Easily availability B) High heat transfer coefficient C) Resistance to corrosion D) Resistance to failing - Answer: High heat transfer coefficient 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 - Answer: Metal or Carbon 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 the refrigerant pressure is lowest C) Where no liquid refrigerant is present D) That is outside the evaporator - Answer: Where no liquid refrigerant is present 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 - Answer: The slugging of the liquid refrigerant The purpose of wear rings in a centrifugal pump is to A) Minimum water leakage around the shaft B) Center the impeller in the pump casing C) Prevent wearing of the pup housing and impeller D) Act as a bearing to reduce axial motion after wears occurs - Answer: Prevent wearing of the pup housing and impeller 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 - Answer: Compressor suction Capactitors 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 to lag the voltage B) Store electrical charges during starting and running the motor C) Convert electrical to magnetic and then to mechanical D) Defrost refrigerant cooled motors - Answer: Store electrical charges during starting and running the motor 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 - Answer: High volume low pressure 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 - Answer: Material safety data sheet When a refrigerant engineer uses a portable compressor recovery unit to remove vapor refrigerant from refrigeration system the removal rate of the refrigerant will gradually slow down A) Vapor density is decreasing B) Refrigerant temperature is dropping C) Compressor speed decreases D) Compressor efficiency is decreasing - Answer: Vapor density is decreasing 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 - Answer: Flammability and toxicity The viscosity of lubrication oil is described by a number, A low viscosity number describes oil that A) Flows easily B) Should not be used with refrigerant C) Flows poorly D) Does not provide good lubrication - Answer: Flows easily An electrically operated control requires 24 volts to operate. To change the available 110 volts to 24 volts A) Recifier B) Step down capacitor C) Low temperature wire D) Transformer - Answer: Transformer What is the primary reason ribbed metal piping is used for electrical wires A) It is easier to install than non-ribbed metal piping B) It allows for flexibility and accounts for vibrations C) It allows for ventilating the heat from wires D) It is less costly to use than non-ribbed metal piping - Answer: It allows for flexibility and accounts for vibrations The British thermal unit (BTU) is the measurement of heat energy. If 10 BTU are transferred to 10 pounds of water, the water temperature increase will be closest to A) 10F B) 1C C) 1F D) 10C - Answer: 1F 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 - Answer: Dry vapor above the saturation temperature 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) Very small bend radius - Answer: Level type tubing bender 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 - Answer: The pump is full of liquid 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 speed up - Answer: Turbine will vibrate violenty 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 - Answer: Difference between the high side and low side pressure 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 - Answer: Cools the motor 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 a superheated system D) Compare temperature to another thermometer - Answer: Place the thermometer in a cup of ice water Under certain circumstances is it ok to chain an exit door A) Yes, to keep your buildings safe from intruders B) Yes, to keep students from leaving school C) No, it is never ok D) Both A and B are correct - Answer: No, it is never ok Cross connections and standpipe risers must be painted A) Green B) Red C) Yellow D) Green with yellow stripe - Answer: Red Why is a refrigerant gauge called a compound gauge A) You can read the pressure on the high side and the low side B) You can read temperature and pressure C) It has scales for different types of refrigerant D) It reads positive pressure and vacuum - Answer: It reads positive pressure and vacuum 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) Refrigerant toxicity C) Asphyxiation D) Refrigeration odor - Answer: Asphyxiation 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 - Answer: Same type of refrigerant inside the machine 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 pump is significantly lower than normal. Which following action would you avoid taking A) Put on an additional condenser water pump B) Flush out the bucket strainer of the condensed water pump C) Send your assistant to check for cooling tower level D) Put on an additional surface condenser pump and lower the chilled water set point - Answer: Put on an additional surface condenser pump and lower the chilled water set point 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 once a week prior to hot works C) Check area day of hot works D) Check area day after hot works - Answer: Check area once a day leading up to hot works Standpipe certificate should be available for A) FDNY and OSHA B) FDNY and building inspector C) FDNY and EPA D) FDNY and NFPA - Answer: FDNY and building inspector When is a chemical fire extinguisher system needed A) Where water is not sufficient B) Pre action system C) Deluge system D) High rise office buildings - Answer: Where water is not sufficient Fireproof decorations in buildings are useful for A) Seasonal purposes B) Don't catch fire in an emergency C) Usually energy efficient D) Help reduce heat load - Answer: Don't catch fire in an emergency What is the lowest temperature a cooling tower can be A) Ambient temperature B) Dry bulb temperature C) Wet bulb temperature D) Between dry bulb and wet bulb - Answer: Wet bulb temperature A single phase 208 VAC circuit has 2 hot wires and the third is A) Spare wire B) Ground C) Control wire D) Common - Answer: Ground With a 75 degree dry bulb and a 73 degree wet bulb the relative humidity is? A) Normal B) Very low C) 100% relative humidity D) Very high - Answer: Very high After recovering liquid refrigerant from a centrifugal chilled the next step is to A) Blow the system out with nitrogen B) Pull a deep vacuum C) Recover vapor D) Leak test system - Answer: Recover vapor 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 - Answer: The melting point is marked on it What is used on an outside pipe to prevent it from freezing A) Capacitor B) Resistor C) Heating coil D) Transformer - Answer: Resistor You are preforming 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 - Answer: Put a non-combustible barrier to protect the sprinkler head 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 - Answer: 10-15 minutes What is the state of the refrigerant entering the compressor on a reciprocating machine A) Vapor B) Superheated vapor C) Saturated vapor D) Liquid - Answer: Superheated vapor The most important reason for installing a muffler in a 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 - Answer: To contain the compressor pulsation noise Of the following, the statement that most accurately charcterizes a hermetic compressor is that A) Typically has a pressure lubrication system B) Will have only the motor enclose in a gas tight housing C) Will have both the compressor and motor enclosed in a gas tight housing D) Is erected in the field - Answer: Will have both the compressor and motor enclosed in a gas tight housing In absence of water chemical treatment in the cooling tower A) Drain the tower every one to two weeks and replace with fresh water B) Punch tubes every week C) Clean condenser pump strainers D) None of the above - Answer: Drain the tower every one to two weeks and replace with fresh water What is the function of a safety head on a compressor A) Capacity control B) Prevent liquid slugging from damaging the valve plate C) Purge air from cylinders D) Prevent friction - Answer: Prevent liquid slugging from damaging the valve plate What does a wiring diagram display A) Wiring of components B) Wiring of switches only C) Switch functions D) All of the above - Answer: Wiring of components What is the order of components on the liquid line of a reciprocating system from the conders 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, kind valve - Answer: King valve, filter drier, solenoid valve, sight glass A high-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 - Answer: Constant level of refrigerant in condenser Filter driers remove A) Air and acids B) Moisture and particles C) Oil and acids D) Moisture and air - Answer: Moisture and particles 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 - Answer: Centrifugal chill water pump What is the most widely used regulation book by operating engineers A) OSHA B) EPA C) BOMA D) NFPA - Answer: EPA 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 back seated B) High and low side front seated C) High side back seated low side front seated D) High side front seated low side back seated - Answer: High side front seated low side back seated 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 You are supplying 46 degree chilled water. All 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 makeup water to the cooling tower D) Increase the speed of the cooling tower fans - Answer: Add additional makeup water to the cooling tower The cooling medium for a cooing tower is A) Air B) Water C) Air and water D) Tower fan - Answer: Air The charge in a TEV sensing bulb us A) Non flammable non toxic B) Similar to refrigerant in system C) Highly toxic highly flammable D) Different type of refrigerant than in system - Answer: Similar to refrigerant in system A FDNY permit is required to conduct hot works for A) Brazing B) Welding C) Use of oxygen and flammable gas D) All of the above - Answer: Use of oxygen and flammable gas