Panasonic U-8MF2E8 Service Manual page 76

7. Charging Compressor Oil
Next follow the instructions in "4-2-1. Cooling operation (for all units)" at the outdoor unit where oil will be charged,
and start cooling operation at all units. When the operating conditions have stabilized, perform steps 1, 2, and 3
in sequence and open the valves. When this is done, the refrigerant pressure from operation forces the oil out of
the oil charge tank, and oil is charged into the outdoor unit from the low-pressure outlet port. From time to time
close the upper valve on the top of the oil charge tank (only this valve) and shake the tank to check the amount of
remaining oil.
High-pressure outlet port
(for ø7.94mm-dia connector)
Low-pressure outlet port
(for ø7.94mm-dia connector)
Suction tube service port
(for ø7.94mm-dia connector)
2
Discharge tube service port
(for ø7.94mm-dia connector)
Liquid tube service port
(for ø7.94mm-dia connector)
Oil balance tube service port
(For 7.94mm-dia. connector)
To terminate the oil charging work, do as follows:
To end the charge process, first close the valve on the high-pressure side of the manifold gauge. Then wait several
tens of seconds after the pressure display on the manifold gauge low-pressure gauge stabilizes (in order to equal-
ize the pressure with the low-pressure outlet port and to vaporize the refrigerant in the charge tank). Then perform
steps 1 and 3 in sequence and fully close the valves. Finally, connect the refrigerant recovery unit to the Lo-gauge
side, shut down all indoor and outdoor units, and then recover the remaining refrigerant in the oil-charging tank,
manifold gauge valves, and connecting hoses. Perform these procedures quickly and securely so that no air can
enter. After, charge the necessary amount of new refrigerant by referring to the "Installation Instructions" that came
with the outdoor unit.
NOTE
To determine the completion of refrigerant recovery, follow the instructions that came with the refrigerant recovery unit.
7-2. If Outdoor Unit Has Not Been Charged with Refrigerant
When a compressor has been replaced or in any other case where the outdoor unit has not been charged with
refrigerant, first charge with refrigerant then follow the instructions in "7-1. If Refrigerant Has Already Been Charged
to Outdoor Unit" and charge with oil.
Or, alternatively, follow the procedure below.
(1) Connect a tube to the oil outlet port on the outdoor unit to be charged with oil. Insert the other end of the tube into
the oil container.
(2) Follow the instructions in "6. Evacuating System," and apply vacuum to the outdoor unit to be charged with oil.
When this is done, oil is charged into the outdoor unit through the oil outlet port.
(3) When the unit has been charged with the designated amount of oil, stop the vacuum pump.
Outdoor Unit Repair Procedures
Procedure 2:
Open the upper valve
Procedure 1:
Open High-side manifold
gauge valve
Manifold gauge
Lo
Connect to
refrigerant
recovery unit
Fig. 12
2 - 16
3WAY SYSTEM
DPR
Upper valve
Lower
valve
Procedure 3:
Hi
Open the lower valve