Recovering Refrigerant - Panasonic R410A Service Manual

3. Recovering Refrigerant

The following equipment and tools are required:
Jumper wire with clips, adjustable wrench, set of manifold gauge valves specially designed for refrigerant R410A
only, vacuum pump, refrigerant recovery unit, pre-purged refrigerant cylinder for recovery (air already evacuated),
and hex wrench (4 mm for liquid tube and 5 mm for gas tube).
3-1. Refrigerant Recovery Procedures (From Outdoor Unit)
(1) Turn off the power of the outdoor unit beforehand (at power mains).
(2) Fully close each service valve on the gas line and liquid line of the outdoor unit.
(3) Connect the outdoor unit's high-pressure and low-pressure outlet ports with the Hi and Lo sides of the
manifold gauge valves using hoses. (See Fig. 2-2)
CAUTION
(4) Connect the manifold gauge valves, refrigerant recovery unit, and recovery cylinder using hoses.
To avoid the entry of air into the refrigerant tubing, carry out this connection work carefully.
1
CAUTION
(5) Locate the AP pins on the control PCB in the outdoor unit and short them using the clips of the jumper wire.
Then restore electrical power to the outdoor unit.
2
CAUTION
3
(6) Carry out refrigerant recovery.
CAUTION
4
5
6
The remaining refrigerant in the outdoor unit may create internal pressure.
Before connecting hoses, be sure to confirm that each of the manifold gauge
valves is tightly closed. Note that the connection ports employ Schrader-type,
press-to-release valves.
For detailed procedures such as connecting the refrigerant recovery unit
with the recovery cylinder and methods used for recovery, follow the specific
instructions that came with the refrigerant recovery unit.
By short-circuiting the AP pins, each electronic expansion valve in the
outdoor unit is forcibly opened as soon as power comes on, which releases
all remaining refrigerant into the recovery cylinder. Since neglecting this
procedure may leave some refrigerant in the system, it is important that you
carry out this step.
To determine the completion of refrigerant recovery, follow the instructions
that came with the refrigerant recovery unit.
Refrigerant
recovery unit
Refrigerant recovery cylinder
Low-pressure outlet port
(For ø5/16" connector)
Manifold
gauge
Lo Hi
Fig. 2-2
2 - 6
Mini VRF SYSTEM
Outdoor Unit Repair Procedures