Panasonic U-10MF1E8 Service Manual page 55

5. Recovering Refrigerant
(2) If the remote controller (CZ-RTC2) is not available for maintenance of the outdoor unit
➀
Determine the outdoor unit where the unit No. setting (S007) (3P DIP switch) (BLU) on the outdoor unit
control PCB is set to No. 1.
➁
Short-circuit the mode-change pin (CN101) on the outdoor unit control PCB of the No. 1 unit. Then
short-circuit the test-run pin (CN023) to start operation. (Short-circuiting the mode-change pin ensures that
heating/cooling operation is not mixed and that all units are operating in either Heating or Cooling mode.)
➂
Check the displays of the indoor unit remote controllers. Check that all units are operating in Cooling mode.
If all units are operating in Heating mode, perform the steps listed below.
With the 3-way valve, it is difficult to determine whether operation is heating or
CAUTION
cooling by touching the tubing.
➃
Release the short-circuit at the test-run pin (CN023) on the outdoor unit control PCB of the No. 1 unit. Then
short-circuit the stop pin (CN104) to stop operation.
➄
Short-circuit the mode-change pin (CN101) on the outdoor unit control PCB of the No. 1 unit.
* Switching of the 4-way valve occurs immediately before operation starts. Therefore it does not change at
this time. (Mode change cannot be judged from the sound.)
➅
Short-circuit the test-run pin (CN023) on the outdoor unit control PCB of the No. 1 unit. Then check the
displays of the indoor unit remote controllers. Check that all units are operating in Cooling mode.
5-2-2. 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. 8, follow the instructions
given in (2) through (6) below. If the service port is instead located in the outdoor side, follow the instructions in
"5-2-3. Refrigerant recovery procedures (2)."
(2) After running the unit in Cooling mode for about 5 minutes as described in "5-2-1. Cooling operation (for all
units)," fully close the discharge line, the liquid line ball valve, and indoor unit ball valve.
(3) Run the unit in Cooling mode for 10 to 20 minutes more.
(4) Fully close the suction line 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. 8) 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.
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
2 - 11
Outdoor Unit Repair Procedures
Suction tube
Discharge tube
Liquid tube
Manifold
gauge
Fig. 8
3-WAY SYSTEM
Service port
Solenoid Solenoid
valve kit valve kit
Indoor unit
2