Scotsman FM1202R Service Manual page 20

FM1202R
OPERATION: Refrigeration
The refrigeration system under low condenser air
temperatures is much the same as it is under
higher temperatures, with the exception that the
resulting low head pressures cause the head
pressure control to close off the liquid line between
the condenser and the receiver. This forces more
DISCHARGE
LINE
HEAD
PRESSURE
CONTROL
VALVE
Low Condensing Temperature
Refrigeration Schematic
LIQUID LINE
KING
VALVE
RECEIVER
November 1992
refrigerant into the condenser (with a small amount
of discharge gas going into the receiver to
maintain pressure until the head pressure is built
back up to the rated gauge pressure of 220 psig).
At that pressure the valve opens up the liquid line
from the condenser to the receiver.
DETAIL OF HEAD
PRESSURE CONTROL
VALVE
LIQUID LINE
VALVE
SUCTION
LINE
COMPRESSOR
Page 20
REMOTE CONDENSER
THERMOSTATIC
EXPANSION
VALVE
EVAPORATOR