Evacuation And Charging Procedure - GE PFSS9PKY Technical Service Manual

Sealed System
The 29-cubic foot units have a series dual
evaporator like previous models, but now have a
new sealed system. They now use a multi-speed
inverter compressor and a 3-way valve.
The compressor function is controlled by the
inverter board mounted in the main board
compartment. The 3-way valve is controlled by the
main board. This valve will switch the unit to freezer-
only cooling when the fresh food temperatures are
satisfi ed.
There are no procedure changes for replacing the
evaporator because the freezer evaporator capillary
is inaccessible inside the cabinet.
The back cluster pipe (see illustration) is a hot loop
of the sealed system. With reduced insulation
thickness in the back of the cabinet, this loop warms
the cabinet behind the evaporators to minimize the
possibility of cabinet sweat.
3-Way Valve
The 3-way valve, like previous models, controls
refrigerant fl ow to the evaporators. When the
refrigerator is off, or in defrost, the valve is open to
both evaporators allowing for equalization.
If both compartments require cooling, the valve
opens to the fresh food only. Refrigerant fl ows
through the fresh food evaporator and then through
the freezer evaporator which has the common
suction line to the compressor. When the fresh food
is satisfi ed, the valve will open to the freezer only
until the freezer is satisfi ed and the refrigerator
cycles off.

Evacuation and Charging Procedure

WARNING:
• Before cutting or using a torch on
refrigerant tubes, recover the refrigerant
from the system using approved recovery
equipment.
• Never charge new refrigerant through the
purge valve. This valve is always located on
the high-pressure side of the system.
• Never apply heat from any source to a
container of refrigerant. Such action will
cause excessive pressure in the container.
• Always wear goggles when working with
refrigerants and nitrogen holding charge in
some replacement parts. Contact with these
gases may cause injury.
1. Attach the hose from the R-134a charging
cylinder to the process tube port on the
compressor.
2. Evacuate the system to a minimum 20-in.
vacuum using the refrigerator compressor and
recovery pump, which is attached to the new
drier assembly.
3. Turn off the recovery pump. Close the ball valve
on the hose connected to the high-side port
connection. Add 3 ounces of R-134a refrigerant
to the system. Let the refrigerator operate and
circulate the refrigerant for 5 minutes.
4. Open the ball valve. Recover the purge/sweep
charge using the recovery pump and the
refrigerator compressor until a 20-in. vacuum
is attained. Close the ball valve and remove the
recovery hose.
5. Charge the system with the exact amount of
R-134a refrigerant specifi ed.
6. Disconnect the power cord to the refrigerator.
This allows the pressure to equalize. After 3 to 5
minutes, the low-side pressure will be positive
and then the hose-to-charging port can be
disconnected.
7. Using an electronic leak detector, check all
brazed joints and both Schrader ports. Reinstall
caps to the Schrader ports.
– 9 –