Panasonic U-8ME1E81 Service Manual page 80

4. Recovering Refrigerant
Refrigerant
recovery unit
Refrigerant recovery cylinder
3
4-3. Recovery of Refrigerant from Entire System
(1) Turn off power to the entire outdoor system.
(2) Short-circuit the AP (Air Purge) pins (CN24) on the outdoor control PCB of all outdoor units, then supply power
to the outdoor units.
* By short-circuiting the AP pins and supplying power to the outdoor units, the solenoid valve in each unit is
forcibly opened and all remaining refrigerant can be recovered.
(3) If any unit has encountered a power failure, follow the instructions in "4-1. Refrigerant Recovery Procedures
(from Outdoor Units)" and perform refrigerant recovery for the faulty outdoor unit.
(4) Connect the manifold gauge to the high- and low-pressure outlet ports (Schrader-type valves) on any outdoor
unit. (Fig. 5)
CAUTION
(5) Connect the manifold gauge valves, refrigerant recovery unit, and refrigerant recovery cylinder. Quickly connect
each part to prevent air from entering the tubing.
(6) Check that each service valve of the gas tubes, liquid tube, and the balance tube for the outdoor unit has
opened, then perform refrigerant recovery.
* If only a single outdoor unit is installed, the balance tube is not used. Therefore, leave this valve closed.
NOTE
To determine the completion of refrigerant recovery, follow the instructions that came with the refrigerant recovery unit.
Manifold
gauge
Lo Hi
High-pressure outlet port
(for ø7.94mm-dia connector)
Liquid tube service port
(for ø7.94mm-dia connector)
Remaining refrigerant may create internal pressure, therefore care should be
taken when connecting the hoses.
Outdoor Unit Repair Procedures
Type 18HP / 20HP
Fig. 5-c
3 - 14
2WAY SYSTEM
Low-pressure outlet port
(for ø7.94mm-dia connector)
Gas tube service port
(for ø7.94mm-dia connector)