Panasonic U-72MF2U9 Service Manual page 72

4. Recovering Refrigerant
4. Recovering Refrigerant
1
Refrigerant recovery cylinder
2
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.
3
4-2-1. Cooling operation (for all units)
4
4-2-2. Refrigerant recovery procedures (1)
Turn off all equipment in system
a faulty unit, let other normal indoor
units run (excluding indoor unit where
5
can independently be turned off
for indoor unit where refrigerant is
6
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
7
Check for leakage in repaired unit H*
Evacuate air from repaired unit H*
Charge refrigerant in repaired unit H* (Amount of charge
should equal that recovered by refrigerant recovery unit)
Change controllable number of indoor units (including
8
changes in group control and integrated-control settings)
Ready for normal operation
9
Type: 120, 144
Manifold
gauge
Lo
Refrigerant
recovery unit
START
Ball valve is provided
in the indoor unit
YES
When
replacing or repairing
refrigerant is
recovered)
YES
Power
recovered
YES
Open ball valve
END
Hi
4-2-3. Refrigerant
recovery procedures (2)
NO
Figs. 2-a, 2-b
NO
Modify power to permit
turning off power to
refrigerant-recovered
NO
indoor units independently
* Service work performed on indoor units is done simultaneously
using the service ports at the liquid tube side, suction tube side
and discharge tube side ball valves. Refer to each section in the
"Installation Instructions" on refrigerant charging,
leak checking, and evacuation procedures.
2 - 8
2WAY VRF SYSTEM
3WAY VRF SYSTEM
Outdoor Unit Repair Procedures
Outdoor Unit Repair Procedures
Low-pressure outlet port
(for ø5/16" (ø7.94mm)-dia connector)
High-pressure outlet port
(for ø5/16" (ø7.94mm)-dia connector)
Oil balance tube service port
(For ø5/16" (ø7.94mm)-dia connector)
Liquid tube service port
(for ø5/16" (ø7.94mm)-dia connector)
Suction tube service port
(for ø5/16" (ø7.94mm)-dia connector)
Discharge tube service port
(for ø5/16" (ø7.94mm)-dia connector)
Fig. 3-b
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 H*
Evacuate air in repaired unit H*
Charge refrigerant in repaired unit H*
(Amount of charge should equal that
recovered by refrigerant recovery unit)
Open the ball valve
Ready for normal operation
END