Defrosting Circuits and Controls Quiz

What is the primary purpose of a defrost cycle in a refrigeration system?

• To reduce energy consumption

• To enhance the cooling efficiency

• To remove accumulated ice and frost from the evaporator

• To increase the temperature of the refrigerant

Which defrost method uses electric heating elements?

• Hot Gas Defrost

• Natural Defrost

• Reverse Cycle Defrost

• Electric Defrost

What does Hot Gas Defrost utilize to melt frost and ice?

• Hot gas from the compressor discharge

• Heat from the air in the refrigerated space

• Cool gas from the receiver tank

• Electric heating elements

What is Off-Cycle Defrost?

• A method using hot gas

• A method that uses electric heating

• A defrost method using supplementary heat

• A type of natural defrost during non-operating periods

What does Pressure Termination rely on?

• A thermostat sensing temperature

• A pressure controller sensing evaporator suction pressure

• A time clock initiating defrost cycles

• The ambient temperature of the refrigerated space

Which defrost method uses heat pump operation?

• Natural Defrost

• Reverse Cycle Defrost

• Electric Defrost

• Intermediate Gas Defrost

What is the role of a Time Clock in a defrost system?

• To monitor the pressure in the system

• To control the compressor only

• To initiate and terminate defrost cycles at specific intervals

• To measure the temperature of the evaporator

What does Temperature Termination use to sense when to stop defrosting?

• A pressure controller

• A thermostat with a sensing element

• A time clock

• An electric heating element

What is the purpose of Washes in defrosting?

• To monitor the temperature of the refrigerant

• To apply heat to the evaporator

• To wash frost and ice from the coil using water or brine

• To increase the efficiency of the compressor

What is the formula to calculate the number of defrosts per day?

• (Defrost Duration - Runtime) ÷ (24 Hours)

• (24 Hours + Runtime) ÷ (Defrost Duration)

• (24 Hours - Runtime) ÷ (Defrost Duration)

• (Runtime - 24 Hours) ÷ (Defrost Duration)