CFESA REFRIGERATION CERTIFICATION
TEST COMPLETE QUESTIONS AND
ANSWERS GRADED A PLUS PREMIUM
REVIEW SHEET
⩥ What causes evaporators to fail and need replacement.
Answer: Usually corrosion due to the acids from salads and vegetables,
kept uncovered in the cooler
⩥ What can be done to prolong the life of evaporator coil?.
Answer: Clean the coils regularly and keep all foods in the cooler
covered
⩥ What must you consider when selecting an evaporator coil?.
Answer: Physical size, mounting style andBTU rating
⩥ How much distance is recommended between the evaporator in the
cooler wall?.
Answer: 1 1/2 times the height of the coil
⩥ What is the purpose of a nozzle on a large wrapper coil?.
,Answer: To distribute the refrigerant uniformly through the distribution
tubes into the evaporator
⩥ What are the three functions of a condenser?.
Answer: To de-superheat the refrigerant vapor condenses it into a liquid
to sub cool liquid
⩥ What type of tubing is usually used on air cold condensers and why?.
Answer: Steel it holds up better to the heat and high pressures
⩥ Why are fins used on air cold condensers?.
Answer: They help slow down the air and increase heat transfer
⩥ Which way is the airflow directed on most air cold condenser.
Answer: Through the condenser and over the fan motor and compressor
⩥ Why is a shroud needed on air cold condensers.
Answer: To direct and force the air through the condenser
⩥ What happens if the shroud is broken or gone?.
Answer: Air will take the path of least resistance come over and through
the sides of the area between the condenser and the fan
,⩥ How should the fan blade be positioned on a force air condenser?.
Answer: About half of the pitch sticking out through the motor side of
the shroud opening
⩥ What is the problem with forced air cooled condensers in common
commercial kitchen areas?.
Answer: They become Laden with grease vapors from cooking process
if there's a building air balance problem
⩥ What is a remote air cool condenser.
Answer: A condenser remote from the compressor and evaporator
located outdoor outdoors
⩥ What is the advantage of remote air cooled condensers?.
Answer: Not affected by grease favors and kitchens pushes heat off
outside instead of inside
⩥ Why is it so important to keep air cool condensers clean.
Answer: To provide maximum heat transfer and normal discharge
pressure
⩥ How do you clean an air cold condenser?.
Answer: Compressed air or CO2 in a stiff brush coils with grease will
require chemical cleaning
, ⩥ What temperature rises designed into air cooled condensers.
Answer: 8 to 12 low temp 13 to 17 medium temp 18 to 22 high temp all
with system underload
⩥ How do you clean a scaled shell and tube condenser?.
Answer: Circulating the lining solution with an acid pump
⩥ What is the function of a metering device?.
Answer: To lower the pressure of the refrigerant, and therefore the
temperature of the refrigerant entering the evaporator
⩥ How can you tell if a cat two system is undercharged.
Answer: You will have high superheat, low Subco and low capacity for
cool
⩥ How can you tell if a cap tube system is overcharged.
Answer: Higher than normal head pressure, high sub, coolant and lower
superheat, resulting possible refrigerant flooding back to the compressor
⩥ What is the best way to charge a cap tube system?.
Answer: Wait in the charge that's on the data plate then charge to proper
sub, coolant, and superheat when the boxes near its operating temp
TEST COMPLETE QUESTIONS AND
ANSWERS GRADED A PLUS PREMIUM
REVIEW SHEET
⩥ What causes evaporators to fail and need replacement.
Answer: Usually corrosion due to the acids from salads and vegetables,
kept uncovered in the cooler
⩥ What can be done to prolong the life of evaporator coil?.
Answer: Clean the coils regularly and keep all foods in the cooler
covered
⩥ What must you consider when selecting an evaporator coil?.
Answer: Physical size, mounting style andBTU rating
⩥ How much distance is recommended between the evaporator in the
cooler wall?.
Answer: 1 1/2 times the height of the coil
⩥ What is the purpose of a nozzle on a large wrapper coil?.
,Answer: To distribute the refrigerant uniformly through the distribution
tubes into the evaporator
⩥ What are the three functions of a condenser?.
Answer: To de-superheat the refrigerant vapor condenses it into a liquid
to sub cool liquid
⩥ What type of tubing is usually used on air cold condensers and why?.
Answer: Steel it holds up better to the heat and high pressures
⩥ Why are fins used on air cold condensers?.
Answer: They help slow down the air and increase heat transfer
⩥ Which way is the airflow directed on most air cold condenser.
Answer: Through the condenser and over the fan motor and compressor
⩥ Why is a shroud needed on air cold condensers.
Answer: To direct and force the air through the condenser
⩥ What happens if the shroud is broken or gone?.
Answer: Air will take the path of least resistance come over and through
the sides of the area between the condenser and the fan
,⩥ How should the fan blade be positioned on a force air condenser?.
Answer: About half of the pitch sticking out through the motor side of
the shroud opening
⩥ What is the problem with forced air cooled condensers in common
commercial kitchen areas?.
Answer: They become Laden with grease vapors from cooking process
if there's a building air balance problem
⩥ What is a remote air cool condenser.
Answer: A condenser remote from the compressor and evaporator
located outdoor outdoors
⩥ What is the advantage of remote air cooled condensers?.
Answer: Not affected by grease favors and kitchens pushes heat off
outside instead of inside
⩥ Why is it so important to keep air cool condensers clean.
Answer: To provide maximum heat transfer and normal discharge
pressure
⩥ How do you clean an air cold condenser?.
Answer: Compressed air or CO2 in a stiff brush coils with grease will
require chemical cleaning
, ⩥ What temperature rises designed into air cooled condensers.
Answer: 8 to 12 low temp 13 to 17 medium temp 18 to 22 high temp all
with system underload
⩥ How do you clean a scaled shell and tube condenser?.
Answer: Circulating the lining solution with an acid pump
⩥ What is the function of a metering device?.
Answer: To lower the pressure of the refrigerant, and therefore the
temperature of the refrigerant entering the evaporator
⩥ How can you tell if a cat two system is undercharged.
Answer: You will have high superheat, low Subco and low capacity for
cool
⩥ How can you tell if a cap tube system is overcharged.
Answer: Higher than normal head pressure, high sub, coolant and lower
superheat, resulting possible refrigerant flooding back to the compressor
⩥ What is the best way to charge a cap tube system?.
Answer: Wait in the charge that's on the data plate then charge to proper
sub, coolant, and superheat when the boxes near its operating temp
