Panasonic U-8MF2E8 Service Manual page 68

4. Recovering Refrigerant
4-2. Refrigerant Recovery Procedures (Indoor Unit)
The flowchart below shows the refrigerant recovery procedures you must follow when replacing or repairing the
indoor unit due to trouble in the refrigerant circuit.
4-2-1. Cooling operation (for all units)
Ball valve is provided in the indoor unit
4-2-2. Refrigerant recovery
Turn off all equipment in system
When replacing or repairing a faulty
unit, let other normal indoor units run
2
(excluding indoor unit where refrigerant
Power can independently be turned off
for indoor unit where refrigerant is
Change controllable number of indoor
units (including changes in group
control and integrated-control settings)
Other indoor units can operate normally
Replace or repair faulty unit
Check for leakage in repaired unit
Evacuate air from repaired unit
Charge refrigerant in repaired unit
(Amount of charge should equal that
recovered by refrigerant recovery unit)
Change controllable number of indoor
units (including changes in group
control and integrated-control settings)
Ready for normal operation
Service work performed on indoor units is done simultaneously using the service ports at the liquid (narrow tube) side and the
gas (wide tube) side ball valves. Refer to each section in the "Installation Instructions" on refrigerant charging, leak checking, and
evacuation procedures.
4-2-1. Cooling operation (for all units)
(1) If the remote controller (CZ-RTC2) is used for maintenance of the outdoor unit
1 Connect the outdoor unit maintenance remote controller to the RC connector (CN73) (3P) (BLU) on any one
of the outdoor unit control PCBs. Then start a test run of all units. (Press and hold the
4 seconds or longer.)
2 Press the
Refer to the test run service manual for the detail of the outdoor maintenance remote controller operation. It
may be possible to determine whether operation is cooling or heating by touching the gas tubing.
Cooling : low temperature (20
Heating : high temperature (60
CAUTION
START
NO
YES
procedures (1)
NO
is recovered)
YES
NO
recovered
YES
Open ball valve
END
(MODE) button and change to cooling operation and ensure that the cooling is per-formed.
or lower)
or higher)
The gas tubing becomes hot (60
not to be burnt when touching the tubing.
4-2-3. Refrigerant recovery
procedures (2)
Fig. 2
Modify power to permit turning off
power to refrigerant-recovered
indoor units independently
or higher) in heating mode. Be careful so as
2 - 8
3WAY SYSTEM
Outdoor Unit Repair Procedures
Turn off all equipment in system
Replace or repair faulty unit
Check for leakage in repaired unit
Evacuate air from repaired unit
Charge refrigerant in repaired unit
(Amount of charge should equal that
recovered by refrigerant recovery unit)
Ready for operation
END
Replace or repair faulty unit
Check for leakage in repaired unit
Evacuate air in repaired unit
Charge refrigerant in repaired unit
(Amount of charge should equal that
recovered by refrigerant recovery unit)
Open the ball valve
Ready for normal operation
END
(CHECK) button for