OPERATION: Refrigeration
Beginning at the compressor, the refrigerant
502 is compressed into a high temperature
gas. The discharge line directs this gas to the
condenser. At the condenser (air or water
cooled) the gas is cooled by either air or water
and it then condenses into a liquid. This high
pressure liquid then goes through the liquid
line to the expansion valve. The thermostatic
expansion valve meters liquid refrigerant into
the evaporator, the volume of liquid refrigerant
depending upon the temperature of the
evaporator; warmer evaporators get more
refrigerant and colder evaporators get less. At
the evaporator, the refrigerant enters an area
of relatively low pressure, where it can easily
"boil off" or evaporate. As it evaporates, it
absorbs heat from the evaporator and
whatever is in contact with it (such as the
water inside it). After the evaporator, the
refrigerant, now a low pressure vapor, goes
through the suction line back to compressor,
where the cycle is repeated.
CONDENSER
FAN
MOTOR
LIQUID
LINE
THERMOSTATIC
EXPANSION
VALVE
SUCTION LINE
EVAPORATOR
GEAR
MOTOR
COMPRESSOR
HIGH PRESSURE
CUT OUT SWITCH
DISCHARGE
LINE
Refrigeration Schematic
NM650
January, 1991
Page 15
