New York City Refrigeration License Exam I Practice

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• You are operating a 2,000 ton steam-driven turbine centrifugal system providing 46 F chilled water; one building is unsatisfied. What action should you take?
• A TXV is used to maintain constant evaporator superheat by regulating what?
• For charging a 60-ton plant with R134A, where is the charging valve most likely located?
• What is the primary method used to control capacity in a centrifugal compressor?
• Which type of pump is commonly used to move chilled water in a central cooling system?
• How does a cylinder unloader operate on a reciprocating compressor?
• Which event would indicate that the cooling tower is not being air-cooled effectively?
• Regarding fire safety, which ASHRAE refrigerant safety classification indicates no flammability and lower toxicity?
• The flash point of compressor lubricating oil should be:
• Which device is intended to limit refrigerant loss during relief events?
• Non-condensable gases traveling with refrigerant usually accumulate in which component?
• Copper and aluminum are frequently used for condenser tubes in refrigeration systems because of which property?
• If the diameter of a pipe increases while keeping the length constant, how does the volume of the pipe change?
• What type of heat is removed from the refrigerant in a condenser?
• A wiring diagram primarily shows what in an HVAC system?
• Of the following, centrifugal refrigerant machine is best characterized by:
• Why is a pressure relief valve considered better than a fusible plug?
• The primary way of achieving capacity control of a centrifugal compressor is:
• If a panel on a large centrifugal refrigeration system indicates a water flow problem, what is the recommended first step?
• A refrigeration engineer notes excessive cycling of the temperature control on a reciprocating compressor unit. The crankcase temperature is high, the discharge temperature is low, and the suction line temperature is high. Which fault is most likely causing these conditions?
• During a routine line inspection, the TXV bulb is found on the floor. Where should the bulb be attached for proper meter operation?
• In a multi-stage centrifugal compressor, which statement is true about the stages?
• From four valve types, which is most effective for controlling pressure in a refrigeration system?
• The flash point relationship for compressor oil must be:
• A 30-ton cooling system removes how many BTU per hour?
• To isolate a dual pressure relief valve while the system remains in service, which valve type should be used?
• Clogged air louvers under an induced draft cooling tower will produce which result?
• What is the minimum requirement an engineer needs to log readings?
• In indirect low-temperature refrigerant systems, using glycol as the intermediate cooling medium offers which main advantage?
• Which component is responsible for maintaining evaporator superheat in a chilled refrigerant system?
• Which ASHRAE refrigerant classification would FDNY consider most hazardous in a fire situation?
• Of the following, centrifugal chillers are best described as?
• Which refrigerant in commercial and industrial systems has the highest latent heat and refrigerating effect?
• A centrifugal water pump is considered to be fully primed when
• A muffler in a refrigeration system is installed between which two components?
• The function of the safety head on a compressor is to prevent what issue?
• A campus refrigeration system with noisy condenser water pump #1, fluctuating discharger gauge, and hot motor: what action should you take?
• Electric defrosting devices used with evaporator units are classified as which type of component?
• Which document would you consult to understand the hazards, safe handling, and first aid measures for a chemical used in the refrigeration plant?
• In most semi hermetic compressors, the suction vapor is used to
• In the listed sequence of components on the liquid line from condenser to TEV, which component appears last?
• How much additional refrigerant is allowed in a machine room?
• When charging refrigerant on the low side of a reciprocating machine with manifold gauges, what is the position of the manifold?
• A decrease in the efficiency of a reciprocating compressor is most likely caused by which of the following?
• What is the main advantage of a forced-draft cooling tower over a natural-draft cooling tower?
• What is the correct interpretation of a centrifugal pump being fully primed?
• In a large centrifugal refrigeration system, if the cooling tower water level is very low, what is a common initial corrective step?
• 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?
• What is most accurate about fire alarm books?
• Regardless of ASHRAE refrigerant classification, if there is a refrigerant leak, which hazard should the engineer be aware of?
• Gland steam is used to seal which part of a steam turbine?
• When you are finished leak testing with R22 and nitrogen the next step would be?
• You find that the check valve on a centrifugal pump is leaking. When would the most damage be caused to the pump?
• An inline refrigerant cleaning system that may be used with a centrifugal compressor containing R123 refrigerant is:
• Ammonia refrigerant ASHRAE classification is which?
• Copper tubing refrigerant lines must be installed for a new system. To prevent collapse at bends, which tool should the refrigerant engineer use?
• Which situation is most likely to cause high condenser pressure despite clean tubes?
• 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 core power motor operating 9 hours in kilowatt-hours is closest to:
• If a cube has 12-inch sides, its volume in cubic feet is?
• What is the advantage of a shell and tube condenser, as opposed to a shell and coil condenser?
• If a valve handle is at a 45-degree angle, what is the valve's position?
• Which safety feature relieves overpressure in a low-pressure centrifugal refrigeration system?
• All liquid has been recovered from a system to be overhauled; the system
• Where must Material Safety Data Sheets be located?
• What is the function of a safety head on a compressor?
• In a hermetic compressor, the motor is enclosed in a gas-tight housing along with the compressor.
• Which instrument is specifically used to measure electrical resistance to diagnose winding faults in motors?
• In a multi-stage centrifugal compressor, which statement about the stages is correct?
• A BTU is a unit of heat. If 10 BTU are transferred to 10 pounds of water, the water temperature rise will be closest to:
• In refrigerant management, which term describes extracting refrigerant and cleaning it for reuse without reclamation requirements?
• Which description best matches a standpipe hose outlet?
• Which practice helps avoid water and moisture problems in a refrigerant system?
• An engineer suspects a short in the motor windings has caused the motor to trip on overload. What instrument should be used to check the motor?
• A circuit breaker has a similar function as what?
• With a 75 degree dry bulb and a 73 degree wet bulb the relative humidity is?
• In relation to the suction pressure of a compressor, the oil pressure gauge should read approximately what relative value to suction pressure?
• FDNY is most concerned with which ASHRAE refrigerant classification?
• Which option describes the function of the equipment that removes non-condensables from the condenser?
• The cooling medium for a cooling tower is?
• Why are copper and aluminum commonly used for condenser tubes in refrigeration systems?
• In the standard liquid-line sequence, which component provides a visual indication of liquid refrigerant presence?
• Which option best explains why ribbed metal conduit might be used for wiring near a refrigeration system?
• How often must emergency power testing be performed?
• What component is primarily responsible for controlling turbine speed by adjusting steam admission?
• A chilled water pump is cavitating. Which of the following is the most likely cause?
• Which outcome is associated with critical speed in rotating machinery like turbines?
• An inline refrigerant handling system suitable for a centrifugal compressor using R123 is used primarily to recover refrigerant for reuse. This system is called:
• A refrigeration system uses a 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, what condition may occur?
• On a refrigerant chart using Celsius, if the temperature reads 5 degrees, what is the corresponding Fahrenheit temperature?
• What is the most likely reason for frost on the suction line and part of the compressor?
• Which of the following describes the rated cooling capacity of a 30-ton system?
• From the condenser to the TEV, what is the correct order of liquid-line components?
• Which valve arrangement allows maintenance on a relief valve while the system remains in service?
• A condenser water pump is connected to a suction pipe 75 feet long and 12 inches in diameter. If this pipe is completely drained, approximately how many gallons of water will be obtained?
• Which condition can lead to a starved evaporator in a refrigeration system?
• Under NYC fire code, refrigerant storage containers must be approved by which organization?
• Which device on a compressor is used to manage lubrication by adding or removing oil?
• What action is recommended when instrumentation detects a sudden rise in vibration near the turbine's operating range?
• Where is the charging valve typically located in a large R134A system?
• The sole refrigeration engineer on duty may leave the building’s refrigeration system when it is operating only when?
• Filter driers remove:
• The total heat to be removed by the condenser equals the heat picked up in the evaporator plus what?
• If a sprinkler system has been off-line for two days, how often should it be inspected until it is back in service?
• If water treatment is neglected in a refrigerant system, condenser pressure tends to rise.
• In an indirect refrigeration system, which would not be used as a cooling medium for the building spaces?
• What is the device used to measure the speed of a turbine?
• The most likely cause of condenser water pump cavitation is:
• What is the most widely used regulation book by operating engineers?
• Which ASHRAE refrigerant safety classification denotes the most flammable?
• What is the responsibility of a B29 COF holder?
• Which statement best characterizes a hermetic compressor?
• Which of the following is NOT typically considered a pump component?
• What is the function of the vacuum breaker in a steam turbine?
• What does the drip from the packing gland indicate in a centrifugal pump?
• If refrigerant water and oil are observed together in a container, the fluids would settle from top to bottom as:
• According to MSDS, R134A is described as a
• Which item is not required to have flame resistant treatment?
• Should you be concerned about a 55F chilled water supply used for human comfort, and why?
• The purpose of chemical additives in cooling tower water is to:
• The process by which refrigerant is extracted and cleaned for reuse without requirements for reclamation is called:
• Which valves control the water level in the surface condenser hot well of a steam turbine?
• The purpose of wear rings in a centrifugal pump is to:
• What is the state of refrigerant entering the compressor on a reciprocating machine?
• Where is the muffler located?
• What typically happens to suction pressure after a reciprocating compressor is shut down on a low-pressure cut-out?
• An engineer would expect a relief valve to start function at a pressure:
• Information about the physical and chemical properties of a hazardous material can be found in which document?
• Which component on manifold hoses helps minimize refrigerant loss?
• If the resistance in a circuit is cut in half, how does the power factor change?
• How long must a Fire alarm log book be kept?
• Which information is not contained in a Material Safety Data Sheet (MSDS)?
• Under normal operation, what is the state of refrigerant entering the compressor?
• A pipe with 8 feet in diameter and 12 feet long contains approximately how many gallons?
• Fusible plugs on a condenser have what information marked on them?
• What is the function of the turbine auxiliary oil pump?
• When will the BTU transfer between evaporator and condenser be greatest?
• Under the New York City fire code, refrigerant storage containers must be approved by which organization?
• To convert water at 32°F to ice at the same temperature, what must the refrigeration system remove?
• Which condenser condition contributes to greater refrigerant cycle efficiency?
• Under what condition would an FDNY permit be required for hot work?
• The rupture disc for a low-pressure centrifugal refrigeration machine is normally located on the:
• How is the compressor safety head best described?
• A psychrometer is used by refrigeration engineers to measure:
• What maintenance action is recommended when a cooling tower lacks water chemical treatment?
• What is ammonia's refrigerant ASHRAE classification?
• Which type of compressor is typically controlled by a hot gas bypass valve for capacity control?
• A refrigeration system controlled by a TXV shows high discharge pressure and high normal sub-cooling. What is the most probable cause?
• If all liquid has been recovered from a system to be overhauled, what is the recommended pre-opening procedure?
• An automatic expansion valve maintains a constant what in the evaporator?
• Under normal condition, the refrigerant enters the compressor as a:
• Neglecting condenser water treatment, the first operational symptom is what?
• Which device protects a steam turbine from excessive speed, preventing overspeed conditions?
• What is the radius of a pipe with a 12-inch diameter?
• How long does it take to warm up a steam turbine?
• What happens when a steam turbine reaches critical speed?
• Which refrigerant safety classification indicates no flammability and lower toxicity?
• If a centrifugal compressor has suction pressure of 3 psi and discharge pressure of 10 psi, with atmospheric pressure 14.7 psi, the ratio of absolute discharge pressure to absolute suction pressure is closest to:
• If 29.92" Hg is equal to 14.7 psia, then 26" Hg converts to what is psia?
• A pipe with 6 feet in diameter and 8 feet long contains approximately how many gallons?
• Which of these compressors is not a positive displacement type?
• When is a chemical fire extinguisher system needed?
• Why is a refrigerant gauge called a compound gauge?
• 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?
• Cross connections and standpipe risers must be painted what color?
• In a chilled water system with an air-cooled condensing unit on a roof during cold weather, what type of protection is used?
• To bring an additional pump online in a multi-pump system, what sequence should be followed?
• What is one of the pre hot-work procedures performed before hot works?
• Which factor should be considered to ensure safe operation when replacing a high-side gauge?
• A water chiller with a reciprocating compressor, a thermostatic expansion valve and an air cooled condenser. A restriction in the liquid line would result in:
• A refrigeration compressor has failed to start. After verifying that the electrical circuit to the motor, including all switches and circuit breakers, is complete, the next item to check would likely be which?
• Where is the most likely time for damage to occur if a centrifugal pump's check valve leaks?
• Liquid refrigerant that has passed through a metering device is?
• In Phase II fireman's service, who is allowed to control the elevator?
• Which symptom directly indicates a turbine has reached critical speed?
• The Kingsbury thrust bearing in a steam turbine is designed to maintain which type of shaft alignment?
• What must operators monitor to prevent damage when a turbine may approach critical speed?
• In a refrigeration system that uses chilled water as the cooling medium, a gauge reading the refrigerant saturation pressure is most useful for estimating which of the following?
• Centrifugal chillers are best described as units with which combination of tonnage and operating pressure?
• Which of the following does not require flame resistant treatment?
• Electric defrost devices used on evaporators are classified as which type of heating element?
• How much does 2.5 gallons of water weigh?
• What is the minimum frequency for an engineer to log readings during a shift?
• In a three-ton capacity reciprocating commercial refrigeration system, the most common metering device is what?
• During Phase II fireman's service, which statement is correct?
• Critical speed in turbine operation is best described as a condition where the machine experiences what?
• While operating an R-22 single acting compressor system, oil foaming in the crankcase is most likely caused by a:
• In a parallel setup with two centrifugal condenser water pumps, one at max capacity, what is the most likely effect if you throttle back the discharge of the other pump?
• If two condenser water pumps run in parallel and one pump is throttled, what is the effect on total flow to the condenser?
• Liquid level gauge glasses (except bull's eye) are generally equipped with which type of valve?
• A FDNY permit is required to conduct hot works under which condition?
• Under which arrangement of evaporator and condenser temperatures would the BTU transfer be the greatest?
• For proper metering, where should the TXV sensing bulb be mounted?
• Which sequence correctly describes the startup steps for a centrifugal chiller?
• If the condenser water pump fails, what is the most likely immediate effect on the refrigeration cycle?
• Compared with a simple straight-tube condenser, a shell and coil condenser is typically favored for its?
• How would you calibrate a thermometer?
• In indirect low-temperature refrigerant systems, using glycol as the intermediate cooling medium instead of salt brine provides which main advantage?
• When a steam turbine reaches critical speed, the immediate mechanical response is typically?
• What is the function of the oil charging port on a compressor?
• Which component does not typically vary refrigerant flow in a system?
• An electrically operated control requires 24 volts to operate. To reduce 110 volts to 24 volts you will need:
• Which consequence is most likely when a rotating turbine is driven through its natural frequency?
• Which device is commonly used to modulate refrigerant flow by varying the amount of liquid refrigerant admitted?
• An inline refrigerant cleaning system is advisable to
• According to code, emergency power is not required in which setting?
• If the cooling tower is on the 8th floor, how many feet above the first floor is it?
• The suction service valve of a reciprocating compressor is front seated and the machine runs until the low pressure cut-out shuts the compressor off. When the machine is stopped, suction pressure tends to rise rapidly. What is the most probable cause?
• What is the most important requirement for an evaporator to function effectively?
• Standpipe certificate should be available for which authorities?
• 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?
• Cooling tower water additives are used to:
• To maximize evaporator effectiveness, what characteristic should it possess?
• What device automatically controls the speed of a steam turbine?
• What is the primary purpose of installing a muffler on a reciprocating refrigerant machine?
• What type of refrigerant is found inside the machine's gauges?
• Which of the following describes the effect of critical speed on a steam turbine?
• Regarding the functioning of a steam turbine, why is it advisable to keep moisture in the inlet as low as possible?
• In a water chiller system using refrigerant R123, a leak in the evaporator shell is most likely to cause which condition?
• A water pump with a discharge head of 92 feet of water corresponds to approximately how many psi?
• Water regulating valves are used to?
• The middle port on a gauge manifold is typically connected to which device?
• Reaching the critical speed in a steam turbine most directly leads to which condition?
• During hot works near a sprinkler head, what should you do to prevent the fire alarm from triggering?
• Modern compressors usually seal the rotating shaft as it exits the compressor housing with a spring seal made of:
• If a refrigerant temperature chart uses Celsius and 4°C equals 39.2°F, what is the Fahrenheit equivalent?
• Which type of refrigerant system is least likely to leak refrigerant into the building space being cooled?
• What type of refrigerant do you need FDNY approval for?
• How do you start a centrifugal chiller?
• Which statement about forced-draft cooling towers is true?
• On a steam turbine, which factor could cause the atmospheric valve to open?
• The ratio of the actual vapor pressure to the saturated vapor pressure at a given temperature defines what?
• Given gauge suction pressure 3 psi, gauge discharge pressure 10 psi, atmospheric pressure 14.7 psi. The ratio of absolute discharge pressure to absolute suction pressure is closest to:
• If a condenser water pump shows noise, fluctuating gauge readings, and the motor runs hot, the recommended action is:
• If the insulation on the thermal bulb line to the suction pipe near the evaporator fails in a room at 85F, what is the likely consequence?
• Which valve is mounted on the top of the valve plate in a typical reciprocating compressor?
• The oil collected in an oil separator is typically returned to which component?
• The amount of electrical power used to operate a solenoid valve or a motor is measured in what unit?
• What type of sprinkler system needs inspecting?
• In order for a refrigerant to become superheated it must be heated in a section of the low-side refrigerant line:
• In a building with a multilane standpipe system, how does each zone get water supply?
• A standpipe system will be out of service for two days. How long should there be a fire watch?
• A high-side float valve is used to maintain what in the evaporator?
• To improve the efficiency of the centrifugal refrigerant compressor, which action is beneficial?
• During unloading, what valve condition is maintained?
• In a condenser system, energy balance states total heat rejected equals heat picked up in evaporator plus heat of compression. Which statement describes this energy balance?
• In a multi-stage centrifugal compressor, the volumes of the stages are typically which of the following?
• When replacing a gauge on the high side, the pressure graduation should be at least how many times the design pressure?
• If a cold front causes a sudden temperature drop, the thermostat will cause the solenoid valve to do what?
• The inline refrigerant cleaning system is advisable to
• A condenser pump circulates water at 85F in, 88F out. If the condenser pressure is high while tubes are clean, which is a likely cause?
• Oil collected in an oil separator is generally returned to which component?
• What is a compressor safety head?
• Which statement correctly identifies the starting point for relief valve operation?
• Which device maintains the level of the refrigerant in the evaporator?
• What is the cross-sectional area, in square inches, of a pipe with a 12-inch diameter?
• Which refrigerant type requires FDNY approval?
• A rooftop cooling tower connected to a basement pump shows 140 PSIG at the pump inlet with the pump off. The corresponding water column height is closest to which value (feet)?
• A single phase 208 VAC circuit has 2 hot wires, the third is the?
• A motor winding is touching the inside of the motor housing. This could result in:
• What is the lowest temperature a cooling tower can operate at?
• The heat removed in a condenser consists of
• What specific data is provided on a fusible plug used in condensers?
• When an expansion valve is operating properly, at the end of the evaporator will contain what?
• Fireproof decorations in buildings are useful for?
• What does a wiring diagram display?
• What is the cooling medium for an evaporative condenser?
• An equalizer line on a TXV is used to:
• Standpipe certificates should be available to which parties?
• Why is it important to avoid reaching critical speed in a steam turbine?
• A solenoid valve opens when what occurs?
• If a refrigerant saturation pressure gauge is used in a system with chilled water, the reading primarily indicates the temperature of which component?
• The viscosity of lubrication oil is described by a number. A low viscosity number describes oil that:
• ASRHAE refrigerant safety group classification system is based on which two characteristics?
• What is the primary risk when a turbine hits its critical speed?
• In a multilane standpipe system, how is water supplied to each zone?
• In a cascade refrigeration system, what is the primary reason to use at least two compressors?
• In a steam turbine system, how is the water level controlled in the surface condenser hot well?
• Inlet moisture in a steam turbine should be kept low primarily to minimize wear on:
• Which component is listed as the first element in the liquid line sequence from condenser to TEV?
• A reciprocating compressor cylinder has a 10 inches bore and 14 inches stroke. The volume of refrigerant, in cubic inches, will be closer to:
• Which property is desirable to maximize energy storage during the refrigerant’s phase change?
• If expansion valve is opened too wide, which of the following system conditions may result?
• Capacity control of a reciprocating hermetic compressor is typically achieved through the operation of which component?
• In cooling tower operation, which temperature reading is used to specify the lower limit?
• There is 7.48 gallons per cubic foot. How many gallons are in a pipe 10 feet in diameter and 5 feet long?
• In a reciprocating system, compressor discharge temperature dropped significantly and suction line pressure is high. Which valve condition may cause this?
• The condenser rejects heat equal to the evaporator heat plus the heat of compression. Which two contributions make up the total heat rejected by the condenser?
• During normal operation, how should operators respond if vibration rapidly increases indicating critical speed?
• A leak in the evaporator shell of an R134A system is likely to cause what protective action?
• Which device is used on an outside pipe to prevent freezing?
• In a multi-cylinder reciprocating compressor that uses cylinder unloaders to regulate capacity, what would occur if some unloaders fail to operate when needed?
• How are the suction and discharge valves of a reciprocating compressor typically mounted relative to the valve plate?
• The suction pressure of a reciprocating compressor is 65 PSIG and the discharge pressure is 120 PSIG. The atmosphere is 14.7 PSIG. The compression ratio is closest to:
• A starved evaporator is most likely caused by which condition?
• Subcooling of the refrigerant occurs in which component of the refrigeration system?
• A refrigeration unit uses a low-side float valve as a metering device and is experiencing short cycling. What does this likely indicate?
• Which condenser design is noted for having less danger of leaks?
• Where must fire alarm books be kept?
• A low side float valve is used to maintain what?
• What is the function of gland steam in a turbine?
• What is the purpose of steam ejectors on the surface condenser of a turbine-driven system?
• Electrical current is measured in which quantity?
• Is it permissible to chain an exit door under any circumstances?
• You are the only engineer on duty with a machine running. A vice president tells you to shovel snow. What should you do?
• In a cascade system, adding a second compressor mainly helps to prevent what?
• If R134A accidentally touches a refrigerant engineer's skin, what first aid should be applied?
• R134A is described as which of the following according to MSDS?
• The most important reason to sub-cool the refrigerant in the condenser is to ensure that which occurs?
• If water treatment is not maintained for a refrigerant system, what is the most likely result?
• A box measures 12 inches by 12 inches by 12 inches. What is its volume in cubic feet?
• Under what condition is a centrifugal water pump called a lift pump?
• Which symptom most reliably indicates an undercharged refrigerant system?
• During a cooling tower check on a large refrigeration system, if the tower cells have very low water levels, which immediate action is appropriate?
• In a reciprocating refrigeration system, the refrigerant at the inlet to the compressor is typically in which state?
• A reciprocating compressor is making a knocking sound during operation. If worn parts are not the cause, what is probably the reason?
• You notice condenser water coming back from the 9-cell cooling tower at 90F; to bring to 85F, which immediate action would you take?
• What is the primary reason ribbed metal piping is used for electrical wires connected to the refrigeration system?
• In the absence of water chemical treatment of a cooling tower, what should you do?
• Which property is desirable in a refrigeration system to optimize energy storage during phase change?
• Which component is commonly found in a pump discharge path to prevent backflow?
• After recovering liquid refrigerant from a centrifugal chiller the next step is to?
• The charge in a TEV sensing bulb is?
• Capacitors are used on refrigerant motors. Which statement describes their function?
• In the event of a refrigerant escape, which hazard should be considered regardless of refrigerant type?
• During operation, engineers monitor to detect potential critical speed by observing what?
• What is the primary purpose of oil in a refrigeration machine?
• Which unit is commonly used to specify a refrigerant charge for small systems?
• What is the standard cooling medium for an evaporative condenser?
• During charging, what is the primary reason for performing a thorough evacuation?
• A superheated vapor is a:
• What is used on an outside pipe to prevent freezing?
• The vessel used for refrigerant recovery is intended for use in which refrigerant-related process?
• If the discharge pressure of the condenser water pump is significantly lower than normal, which action would you avoid taking?
• R-123 refrigerant is classified as which type of refrigerant?
• In a cooling system, neglecting condenser water treatment would most directly raise which indicator first?
• Centrifugal pressure is determined by?
• In a steam turbine, what is the function of the Kingsbury thrust bearing?
• The amount of refrigerant flowing through economizer orifices is determined by
• Manifold hoses should be equipped with which fittings?
• Which statement about centrifugal compressors is true?
• In rotating machinery, what sign is most indicative of crossing the critical speed?
• In a refrigeration system where a low-side float valve is used, what is the primary role of that valve?
• What is not required to be serviced annually?