Fm1200r, Operation: refrigeration, Pump down – Scotsman FM1200R User Manual
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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.
REMOTE CONDENSER
EVAPORATOR
DISCHARGE
LINE
LIQUID LINE
HEAD
PRESSURE
CONTROL
VALVE
RECEIVER
COMPRESSOR
Refrigeration Schematic
KING
VALVE
SUCTION
LINE
THERMOSTATIC
EXPANSION
VALVE
LIQUID LINE
VALVE
FM1200R
November, 1988
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