Commercial Food Equipment Service Association (CFESA) Refrigeration Certification Practice Test

These questions are part of the practice quiz. Start practicing

• What does the capacity of a one horsepower compressor depend on?
• What is the most important line to ensure proper oil return during piping installation?
• During a system operation using R134A, what does the system indicate if the suction pressure falls to 15 psi and then into a vacuum?
• What is a key aspect of maintaining balanced port expansion valves?
• What is a common characteristic of a high-quality vacuum pump used in system evacuation?
• What is the primary function of a fan delay thermostat in commercial freezers?
• If the suction line to a compressor using a TEV is frosted and iced up, it could indicate what issue?
• In a system with R134A operating at 146 psi head pressure and 100°F condenser temperature, what is the subcooling measured?
• According to HACCP food safety regulations, what temperature must coolers maintain?
• Which statement is true regarding R134A?
• Which refrigerant serves as a drop-in replacement for R502?
• What is a possible cause for the suction valves snapping off when the compressor head is removed?
• When sizing the piping for a refrigeration system, which line is most critical?
• What does the milky color of oil in a compressor most likely indicate?
• What are signs indicating a malfunctioning expansion valve?
• When evacuating a refrigeration system, to what micron level should it ideally be evacuated?
• What is a common issue with coolers and freezers that use a coiled discharge line in a pan for condensate removal?
• How does ambient temperature impact refrigeration system performance?
• Where should a trap be installed when piping refrigerant lines in a system with the compressor above the evaporator?
• What is the primary purpose of a refrigeration system in commercial food service?
• What should be done to a grease-laden air-cooled condenser?
• What is the main role of an accumulator in a refrigeration system?
• What is a common reason for the premature failure of replacement compressors?
• Which of the following is a key component in assessing the health of a refrigeration system?
• Which component removes heat from the refrigerant, allowing it to cool and condense?
• What line is typically used to provide heat for evaporating condensate in many commercial reach-in boxes?
• What is important to consider when re-soldering refrigerant lines?
• Where must the sensor bulb on a TEV be mounted?
• Excessive moisture in a reach-in cooler typically suggests what issue?
• Where should a temperature sensor be installed to accurately calculate subcooling?
• What effect does insufficient refrigerant charge have on a refrigeration system?
• How should R404A be charged into a refrigeration system?
• In refrigeration systems, what role does a sight glass play when properly installed?
• What happens when the defrost termination thermostat reaches its temperature limit?
• What is the primary reason a condensing unit located in a restricted space will run higher than normal head pressures?
• What could be a potential risk if the compressor fails in a refrigeration system?
• Why is monitoring ambient temperature crucial in refrigeration systems?
• Where is a run capacitor connected in a motor system?
• What is the best example of the definition of a storage box?
• What is the purpose of an evaporator fan in commercial refrigeration?
• Where must the sensor bulb on a TEV be installed on the suction line?
• What causes a refrigeration system to run continuously?
• A cap tube is ineffective on most commercial refrigeration systems because:
• What symptom might indicate a faulty thermostat in a refrigeration unit?
• Why is superheat crucial in a refrigeration system?
• When should a suction drier be left in the refrigeration line?
• What should be done if an evaporator has an external equalized TEV, but only an internal equalized valve is available?
• In what way does the refrigeration cycle specifically differ from the air conditioning cycle?
• What is the consequence of dirty and clogged evaporator coils?
• Which tool is essential for troubleshooting refrigeration issues?
• What is the maximum temperature a freezer must maintain to ensure proper operation?
• What is the best course of action when there are concerns with refrigerant levels in a compressor with low oil?
• In subcooling calculations, why is the position of the temperature sensor important?
• What leads to effective acid removal from the refrigerant?
• Why must a condenser fan blade be replaced with the exact factory-supplied blade?
• What could lead to a malfunctioning thermal expansion valve?
• What does the start relay disconnect when the motor reaches about 2/3 of its full speed?
• What is a common method to identify leaks in a refrigeration system?
• When checking for correct superheat on a cap tube system, what condition is required?
• What happens to a refrigeration system when moisture is present?
• If a start capacitor rated at 240 uf and 225 volts is faulty, which capacitor can be used instead?
• Which of the following is NOT a main component of a refrigeration system?
• What is a typical symptom of a malfunctioning compressor?
• Which box operates with higher humidity based on the temperature difference?
• What issue is indicated by the oil sight glass showing almost no oil in a compressor?
• An R404A cooler system with a cap tube has a head pressure of 336 psi. What may this indicate?
• Which factor is essential for maintaining optimal performance in a refrigeration system?
• What safety precautions should be observed while working with refrigeration systems?
• What is the primary function of the high-pressure switch in a refrigeration system?
• Which refrigerant is a suitable interim replacement for R-12?
• Why is regular maintenance important for refrigeration systems?
• How do you reduce the superheat on a thermal expansion valve?
• Why are forced air evaporator coils commonly used in refrigeration systems?
• What is the most common cause of leaks in the middle of a copper line?
• After completing repairs on a freezer, why might the temperature stop dropping at 35 degrees?
• Which type of cleaner is most effective for cleaning greasy condenser coils?
• In low temperature climates, what is the most efficient method for temperature control?
• An automatic expansion valve does not:
• A system that runs at a superheat of 1 ° F will likely result in what?
• How many BTUs per hour is one ton of refrigeration equal to?
• What environmental factor significantly impacts the efficiency of condensing units in refrigeration systems?
• When replacing valve plates or service valves, what should be used to lubricate the gaskets?
• Why is measuring compression ratio critical for a compressor's life?
• Why can pressure controls not be used as the sole source of temperature control in outdoor temperature climates?
• If the liquid line out of the liquid line drier is frosted, what does this suggest?
• What happens if the condenser fan fails in a refrigeration system?
• When bubbles are present in a sight glass, what does this indicate when using near azeotropic refrigerants?
• What can help mitigate the issue of bubbles showing in sight glasses with a full charge?
• What pressure corresponds to 20°F on R404A?
• If the oil sight glass in a compressor shows almost no oil and there are no leaks, what should be the next step?
• When evacuating a refrigeration system, which tool is essential to ensure a proper evacuation?
• What is the primary risk of using a run capacitor that is not functioning properly?
• What is the status of contacts on a potential relay when not energized?
• When converting a system from R502 to R404A, what can you do with the TEV?
• What factor can lead to compressor overheating in a refrigeration system?
• What is the benefit of using leak detectors in refrigeration maintenance?
• Why might bubbles appear in sight glasses when using newer near azeotropic refrigerants?
• What effect does temperature have on the performance of refrigeration systems during evacuation?
• What are common refrigerant types used in commercial kitchens?
• What is the main function of a drier in a refrigeration system?
• What is the recommended oil level in the sight glass of a running semi-hermetic compressor?
• What is the purpose of a water regulating valve in a water-cooled condenser?
• How does a balanced port expansion valve differ from other types?
• Where must a static condenser be installed?
• In a potential relay, how is the coil typically wired?
• What should be monitored to prevent damage to relay contacts in a compressor's circuitry?
• How can you confirm that a refrigeration system is properly charged?
• What is a crucial reason for insulating the suction line?
• What does the term 'latent heat' refer to in refrigeration contexts?
• Which component is responsible for maintaining the refrigerant flow in the system?
• What is the main consequence of improper refrigerant charge?
• What is a key disadvantage of using an automatic expansion valve?
• What action is needed to ensure the suction pressure remains the same during testing?
• What function does the evaporator serve in a refrigeration system?
• What is the purpose of a condenser in the refrigeration cycle?
• What type of oil is most commonly used with CFC refrigerants?
• What action should be taken if the condenser is badly clogged?
• Where is the most effective place to remove moisture from refrigerant?
• Why is a proper refrigerant charge critical in refrigeration systems?
• Where is a pump down solenoid valve typically located?
• Is it advisable to install a sight glass in a cap tube system?
• What condition can cause discharge valves and backing plates on a compressor valve plate to be deformed?
• What is a common cause for evaporator failures in reach-in coolers?
• How does a two-stage refrigeration system operate?
• What is the total capacitance of two 100 uf capacitors connected in parallel?
• What role do defrost timers play in commercial refrigeration systems?
• What does icing around a freezer door frame typically indicate?
• What type of maintenance is necessary for condensers in refrigeration systems?
• What commonly contributes to high head pressure in a refrigeration unit?
• What type of contacts are found on a current relay?
• For maximum system efficiency, the TEV superheat for a cooler should be about:
• What characteristic of mineral oil makes it suitable for use with CFC refrigerants?
• What is an effect of not addressing low refrigerant levels?
• What is the role of the condenser in the refrigeration cycle?
• How can you identify a compressor that suffered from liquid slugging?
• Which phrase best describes the proper use for a refrigerated box using a cap tube system?
• Which of the following best describes the process of condensation in a refrigeration system?
• What is the role of an electrical schematic in refrigeration troubleshooting?
• What is the primary function of an accumulator in a refrigeration system?
• What is true about compression ratio in relation to volumetric efficiency?
• What usually causes partial or complete clogging in capillary tubes?
• What is a common reason for a refrigeration system to fail to activate cooling?
• What is the purpose of a low-pressure switch in refrigeration systems?
• What is superheat in the context of refrigeration?
• What should be checked when a compressor is operating inefficiently?
• If a compressor has a rated FLA of 20A but is drawing 26A while running, what is a possible issue?
• Which condition likely indicates a problem when turning off a refrigeration unit?
• How does a compressor function within a refrigeration system?
• How should one check the discharge valves on a compressor?
• What is a sign of a compressor burnout?
• What does proper refrigerant handling ensure?
• What must be matched when replacing an evaporator fan motor?
• Which refrigerant would you convert a walk-in freezer to when replacing the condensing unit on an R502 system?
• Which maintenance task is critical for evaporators?
• What is a thermal expansion valve (TXV) used for in refrigeration systems?
• When is it necessary to evacuate a refrigeration system?
• What happens to the compressor when the condensing temperature at the compressor head reaches 350 °?
• The new interim refrigerants R401A, R401B, and R409A have what characteristic related to heat carrying capacity?
• What effect does a missing condenser fan shroud have on discharge pressure?
• What should be done if there are bubbles in the sight glass of a refrigeration system?
• What is a significant advantage of a balanced port TEV?
• What is the primary purpose of a run capacitor in a compressor system?
• What is a major problem with POE oil?
• How should a fan blade be positioned in an evaporator or condenser?
• How are cooler evaporators typically defrosted?
• Which part of the refrigeration system is crucial for removing moisture?
• Why is refrigerant classification important for refrigeration systems?
• What is subcooling in the context of refrigeration systems?
• What is a characteristic of a near azeotrop refrigerant?
• What is a potential consequence of neglecting regular maintenance on refrigeration equipment?
• What does a dry system indicated by a moisture indicator imply for the refrigeration system's functionality?
• What is a potential consequence of improper refrigerant levels in a refrigeration system?
• When is it necessary to replace a compressor?
• For maximum efficiency, the thermal expansion valve superheat for a freezer should be about:
• Which cleaning agents are advisable for servicing refrigeration coils?
• What is the maximum head pressure for an R404A system operating in an ambient temperature of 85°F?
• What is the importance of proper insulation in refrigeration systems?
• Why is it necessary to remove a grease-covered condenser?
• What should you do if an ohmmeter reads infinity ohms when checking a start capacitor?
• Which component helps prevent corrosion in a refrigeration system?
• What is the purpose of the suction line in a refrigeration system?
• What is a major consequence of undercharging a refrigeration system?
• What maintenance action is necessary for a refrigeration compressor after a defrost cycle?
• A water-cooled condenser that is operating properly will have what characteristic regarding discharge water temperature?
• When replacing driers for newer refrigerants, what size should they be?
• What is the maximum allowable voltage difference for a balanced three-phase compressor?
• What impact do high superheat settings have on a refrigeration system?
• After servicing a cap tube system and replacing the drier with a larger one, what is the best way to recharge it?
• Which condition can lead to compressor failure due to high temperatures?
• A missing condenser fan shroud on a cap tube system will probably lead to what?
• Why do modern three-phase compressors often require crankcase pressure regulating (CPR) systems?
• How does regular maintenance benefit refrigeration systems?
• Which factor is crucial when selecting a pump for evacuating refrigeration systems?
• What occurs to the water flow rate when the condensing unit is off?
• What is the primary benefit of balanced port expansion valves?
• What is the main purpose of using a properly designed drier in a refrigeration system?
• What is the appropriate method to perform a leak check in a refrigeration system?
• What is one way to maintain proper airflow in a refrigeration system?
• What instrument is used to measure the pressure in a refrigeration system?
• Where should a sight glass/moisture indicator be installed in a refrigeration system?
• A dark colored moisture indicator sensor suggests what condition in a refrigeration system?
• What is the primary purpose of a thermal expansion valve in a refrigeration system?
• What determines the size of the metering device needed for a refrigeration system?
• What does the coefficient of performance (COP) indicate?
• When a compressor kicks the circuit breaker while starting, what could be the likely problem if the FLA rating is 7 amps?
• Why is it crucial to adhere to EPA regulations in refrigeration service?
• Which refrigerants are commonly used in commercial refrigeration systems?
• What equipment should be installed to handle the system for newer refrigerants?
• What does it indicate if a compressor is short-cycling?
• Which of the following is a sign of a refrigerant leak?
• What is the primary function of the compressor in a refrigeration system?
• If the shroud is missing from the condenser on a condensing unit, what should be done?
• What preventative measures can help avoid compressor failure?
• What is the maximum allowable discharge temperature to prevent probable compressor failure?
• What can cause frost build-up around the evaporator coil?
• What is a common indicator of a clogged filter in a refrigeration system?
• If the TD of an evaporator coil should be 15 ° and you measure only 5 °, what could be the issue if other pressures check out?
• What is the role of the evaporator in a refrigeration system?
• When should a condenser capacity be assessed?
• Why is it important to clean grease buildup on the condenser fan motor and blade?
• If a cap tube is partially clogged, what is an expected condition?
• What is an essential part of routine maintenance for refrigeration systems?
• In a low-temperature refrigeration system, the majority of Btu of cooling is required to remove what?
• Why is a bleed resistor necessary on a start capacitor?
• What does a dark brown or black color with carbon deposits on a compressor's valve plate indicate?
• Which process occurs in the evaporator coil?
• What could happen if the condenser fan motor is not cleaned?
• What does the compression ratio represent in refrigeration systems?
• What happens at the expansion valve in a refrigeration system?
• What is typically the first sign of a cap tube issue?
• When replacing a refrigerant cap tube with a generic cap tube kit, what is the first step to follow?
• Where is the best location to remove acid from a refrigerant system?
• What causes excess superheat increase on the way to the compressor?
• What is indicated by the terminal marked as 'A' in a common terminal identification?
• When should a cap tube be considered for use in a refrigeration system?
• If an R404A system has a suction pressure of 29 psi and a head pressure of 239 psi, what is the superheat?
• How is a coil on a current relay typically connected?
• What could indicate that a refrigeration system is overcharged?
• What is the procedure for checking the suction valves on a compressor?
• What type of oil is recommended for use with refrigerant R404A?
• What is the typical duration set for defrost timers in commercial freezers?
• In order to maintain proper temperature under various loads, a cooler or freezer located on a front prep line must be equipped with:
• What is the function of a defrost termination thermostat on a walk-in freezer?
• What is the main purpose of the expansion valve in refrigeration?
• What is an interim refrigerant choice for an R502 system with a major leak?
• Where should the discharge temperature be measured in a refrigeration system?
• What environmental factor can contribute to compressor failures?