GE PSH23SGNAFBS Series, Technical Service Manual

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An accumulator has been installed at the outlet of
the evaporator to prevent liquid refrigerant (low
quality) from entering the suction line. Changes in
compressor speed (transition state) can
temporarily reduce refrigerant quality. The
accumulator compensates for this by collecting
and holding up to 2 oz of liquid while allowing
vapor to pass. Within minutes after the
compressor speed change, the system attains a
steady state (becomes stabilized), the liquid
refrigerant in the accumulator vaporizes, and
refrigerant quality returns to normal.
System Pressure
The refrigeration system should maintain a consistent pressure regardless of compressor speed.
Pressure variations, due to changing compressor speed, are minimized by matching the condenser fan
speed and evaporator fan speed to the compressor speed. The condenser and evaporator fans will
always operate at the same speed (low, medium, or high) as the compressor.
Low side system pressure should be between 0 and 5 psig dependant on ambient temperature.
System pressures in an ambient temperature of 75 °F should be:
•••••
High Side – 85 to 90 psig
•••••
Low Side – 1 to 2 psig
Refrigerant Charge
The refrigerant used in the sealed system is R134a. Proper system charge is 6 oz; however, an
additional 0.5 oz is required when adding a filter/dryer. Proper system charge is critical to the operation
of this unit.
Accumulator
HIGH PRESSURE VAPOR
HIGH PRESSURE LIQUID
LOW PRESSURE LIQUID
LOW PRESSURE VAPOR
MIX OF LIQUID AND VAPOR MIX OF LIQUID AND VAPOR
INVERTER COMPRESSOR
0-5 PSIG
1-2 PSIG at
75 ˚F Ambient 70-135 PSIG
85-90 PSIG at
75 ˚F Ambient
COMPRESSOR
CONDENSER EVAPORATOR
CAPILLARY
FILTER-DRYER
ACCUMULATOR
INVERTER COMPRESSOR
0-5 PSIG
1-2 PSIG at
75 ˚F Ambient 70-135 PSIG
85-90 PSIG at
75 ˚F Ambient
COMPRESSOR
CONDENSER EVAPORATOR
CAPILLARY
FILTER-DRYER
ACCUMULATOR
LIQUID ENTERS
THE ACCUMULATOR
GEA01263
Steady State
Transition State