HAC-101 Chap 60 Trailer Refrigeration (Diesel) Test B

Technician A says one major difference between the A/C system and a truck-trailer refrigeration system is that a heating cycle is added to the cooling refrigeration system cycles. Technician B says blower fan speeds are as important in refrigeration systems as they are in air-conditioning systems. Who is correct?

• Technician A only

• Technician B only

• Both Technician A and Technician B

• Neither Technician A nor Technician B

One major difference between the air-conditioning system and a truck-trailer refrigeration system is that a(n).

• Heating cycle is added to the cooling refrigeration system cycles.

• Condenser is not used in the truck-trailer refrigeration cycle.

• Evaporator is used in the heating cycle only in the truck-trailer refrigeration.

• Defrost cycle is added to the air-conditioning system only.

Very damp products are commonly termed

• Perishable

• Heat

• Wet

• Fresh

Heat enters the refrigerated area from sources other than the passenger cabin. All of the following are heat-producing sources, EXCEPT:

• Product that is loaded when warm

• The sun and high outside temperatures

• Doors being kept shut and sealed

• Cargo ripening

Insulation in the ceilings and walls of a refrigerated truck or trailer minimizes heat transfer through

• Absorption

• Convection

• Evaporation

• Conduction

In stand-by mode, the reefer power is sourced from

• The compressor driven by the diesel engine

• The compressor driven by a petrol engine

• The vehicle's battery supply

• A connection to a power grid or shore power source

Technician A says that larger reefer units use compressors that have three cylinders arranged in line. Technician B says larger units use compressors that have four cylinders arranged in a V. Who is correct?

• Technician A only

• Technician B only

• Both Technician A and Technician B

• Neither Technician A nor Technician B

Multi-temp units can regulate temperature using additional

• Compressors

• Condensers

• Accumulators

• Evaporators

During a refrigeration system's cooling cycle, the refrigerant pressure is reduced in the expansion valve, enabling the refrigerant to absorb tremendous amounts of heat as it

• Condenses

• Passes through the evaporator

• Drains out of the valve

• Evaporates

The defrost mode in truck-transport temperature control systems is terminated when coil temperature rises to

• 0°F (-18°C)

• 45°F (7.2°C)

• -20°F (-29°C)

• 55°F (12.8°C)