Refrigeration System

REFRIGERATION CYCLE

Refrigerant Flow
The refrigerant flows in the standard pattern, that is, through the compressor, the condenser, the liquid tank, through the evaporator, and back to the compressor. The refrigerant evaporation through the evaporator coil is controlled by an externally equalized expansion valve, located inside the evaporator case.

Freeze Protection
The compressor cycles go on and off to maintain the evaporator temperature within a specified range. When the evaporator coil temperature falls below a specified point, the thermo control amplifier interrupts the compressor operation. When the evaporator coil temperature rises above the specification, the thermo control amplifier allows compressor operation.

Refrigerant System Protection Triple-pressure Switch
The refrigerant system is protected against excessively high or low pressures by the triple-pressure switch, located on the liquid tank. If the system pressure rises above, or falls below the specifications, the triple-pressure switch opens to interrupt the compressor operation. Triple-pressure switch closes to turn on the cooling fan to reduce system pressure.

Pressure Relief Valve
The refrigerant system is also protected by a pressure relief valve, located in the rear head of the compressor. When the pressure of refrigerant in the system increases to an abnormal level [more than 3,727 kPa (38 kg/Sq.cm, 540 psi)], the release port on the pressure relief valve automatically opens and releases refrigerant into the atmosphere.