OPERATION: Refrigeration
PUMP DOWN
During the pump down cycle (usually initiated by
the circuit board de-energizing the liquid line valve)
the discharge gases flow through their normal path
to the remote condenser, through the head
pressure control, and into the receiver.
At this point the refrigerant flow is stopped by the
closed liquid line valve. This action forces the
refrigerant into the receiver and keeps it out of the
compressor. The pump down continues until the
low pressure control turns the compressor off.
NME654R & FME804R
January 2000
Page 20
DISCHARGE
LINE
LIQUID LINE
HEAD
PRESSURE
CONTROL
VALVE
RECEIVER
COMPRESSOR
Refrigeration Schematic
KING
VALVE
SUCTION
LINE
LIQUID LINE
VALVE
REMOTE CONDENSER
THERMOSTATIC
EXPANSION
VALVE
EVAPORATOR