Panasonic U-8MF2E8 Service Manual page 69

4. Recovering Refrigerant
(2) If the remote controller (CZ-RTC2) is not available for maintenance of the outdoor unit
1 Determine the outdoor unit where the unit No. setting (SW5) (3P DIP switch) (Blue) on the outdoor unit
control PCB is set to No. 1.
2 Short-circuit the test-run pin (CN22) on the PCB to start test run operation.
3 Leave the unit running for a while, and touch the gas tubing with fingers to determine whether the unit is
running in cooling or heating mode.
If it is in heating, follow the step and later procedures.
Cooling : low temperature (20
Heating : high temperature (60
CAUTION
4 Release the short-circuit at the test-run pin (CN22) on the outdoor unit control PCB of the No. 1 unit. Then
short-circuit the stop pin (CN28) to stop operation.
5 Short-circuit the COOL pin (CN40) on the outdoor unit control PCB of the No. 1 unit.
6 Short-circuit the test-run pin (CN22) on the PCB to start test run operation.
4-2-2. Refrigerant recovery procedures (1) (using indoor unit ball valve)
(1) If a ball valve with a service port has been provided in the indoor unit as shown in Fig. 4, follow the instructions
given in (2) through (6) below. If the service port is instead located in the outdoor side, follow the instructions in
"4-2-3. Refrigerant recovery procedures (2)."
(2) After running the unit in Cooling mode for about 5 minutes as described in "4-2-1. Cooling operation (for all
units)," fully close the liquid tube ball valve.
(3) Run the unit in Cooling mode for 10 to 20 minutes more.
(4) Fully close the gas tube ball valve, and stop the operation of all units.
(5) Use hoses to connect the manifold gauge valves, refrigerant recovery unit, and refrigerant recovery cylinder
with each other. (Fig. 4) Do each connection quickly to prevent air from entering the tubing.
CAUTION
(6) Recover the remaining refrigerant from the indoor unit using the refrigerant recovery unit.
NOTE
To determine completion of refrigerant
recovery, follow the instructions that
came with the refrigerant recovery unit.
or lower)
or higher)
The gas tubing becomes hot (60
not to be burnt when touching the tubing.
Remaining refrigerant may create internal pressure, therefore care should be
taken when connecting the hoses.
Ball valve (separately purchased)
Outdoor
unit
side
Refrigerant
recovery
unit
Refrigerant recovery cylinder
Outdoor Unit Repair Procedures
or higher) in heating mode. Be careful so as
Suction tube
Discharge tube
Liquid tube
Manifold
gauge
Lo Hi
Fig. 4
2 - 9
3WAY SYSTEM
Service port
Solenoid Solenoid
valve kit valve kit
Indoor unit
2