#1
Which of the following refrigerants has a low global warming potential (GWP)?
#2
What is the purpose of a compressor in a commercial refrigeration rack system?
To maintain the desired temperature inside the refrigerated space
To remove moisture from the refrigerated space
To pump refrigerant through the system
To regulate the flow of refrigerant
#3
What is the function of an evaporator in a refrigeration rack system?
To increase the pressure of the refrigerant
To absorb heat from the refrigerated space
To regulate the flow of refrigerant
To maintain the desired temperature inside the compressor
#4
Which type of refrigeration system is commonly used in large supermarkets and grocery stores?
Direct expansion system
Single-stage compression system
Ammonia refrigeration system
Absorption refrigeration system
#5
What is the primary refrigerant used in most supermarket refrigeration systems?
R-22
R-404A
R-134a
CO2 (R-744)
#6
Which component of a refrigeration rack system is responsible for controlling the flow of refrigerant into the evaporator?
Compressor
Condenser
Expansion valve
Receiver
#7
Which component of a refrigeration rack system is responsible for condensing the refrigerant from a high-pressure vapor to a high-pressure liquid?
Compressor
Evaporator
Condenser
Expansion valve
#8
What does the term 'floating head pressure' refer to in a refrigeration rack system?
A method of adjusting the head pressure based on ambient conditions
A type of refrigerant with variable pressure properties
A safety feature that prevents over-pressurization
A technique for increasing compressor efficiency
#9
What is the purpose of an accumulator in a refrigeration rack system?
To remove oil from the refrigerant
To store excess refrigerant during low load conditions
To increase the efficiency of the compressor
To regulate the flow of refrigerant
#10
Which of the following is a common method for defrosting evaporator coils in a commercial refrigeration rack system?
Hot gas defrost
Cooling defrost
Electric defrost
Passive defrost
#11
What is the purpose of a crankcase heater in a refrigeration rack system?
To heat the compressor oil and prevent it from solidifying
To regulate the flow of refrigerant
To remove moisture from the refrigerant
To increase the efficiency of the compressor
#12
What does the term 'hot gas bypass' refer to in a refrigeration system?
A method of defrosting evaporator coils
A safety feature that prevents over-pressurization
A technique for regulating the compressor capacity
A type of refrigerant with variable pressure properties
#13
In a cascade refrigeration system, what is the primary purpose of the secondary refrigeration loop?
To cool the condenser
To provide cooling to a lower temperature range
To increase the efficiency of the compressor
To regulate the flow of refrigerant
#14
What is the purpose of a receiver in a refrigeration rack system?
To store excess refrigerant during low load conditions
To increase the efficiency of the compressor
To regulate the flow of refrigerant
To remove moisture from the refrigerant
#15
Which of the following is a common issue associated with commercial refrigeration rack systems during low ambient temperature conditions?
High head pressure
Low suction pressure
Increased compressor efficiency
Reduced refrigerant flow rate
#16
What is the purpose of an oil separator in a refrigeration rack system?
To store excess oil during low load conditions
To increase the efficiency of the compressor
To remove oil from the refrigerant
To regulate the flow of refrigerant
#17
What is the purpose of a desuperheater in a refrigeration rack system?
To remove moisture from the refrigerant
To store excess refrigerant during low load conditions
To increase the efficiency of the compressor
To cool the refrigerant vapor before it enters the condenser