Panasonic U-4LE2E5 Service Manual & Test Run Service Manual page 83

7. Pumping Out Refrigerant from Outdoor Unit
(4) Then slowly close the liquid tube service valve.
* When the low pressure at the outdoor unit to be repaired reaches 0.5 MPa or below, pull out the SCT connec-
tor from the outdoor unit control PCB of that outdoor unit. Then immediately fully close the gas tube valve on
that outdoor unit.
* Pulling out the SCT connector immediately stops all of the outdoor units.
While closing the valves, the rise in discharge temperature or another factor may
CAUTION
cause a protective device to activate, stopping the operation of the outdoor unit. If this
occurs, immediately fully close the gas tube valve on the outdoor unit to be repaired.
(5) Connect the high-pressure gauge side of the manifold gauge to the high-pressure outlet port on the outdoor
unit, and connect the manifold gauge to the refrigerant recovery device. Be sure that no air enters the tubing at
this time.
(6) Short-circuit the AP pin on the outdoor unit control PCB. Then turn ON the outdoor unit power.
When the AP pin is short-circuited and the power is turned ON, all solenoid valves
in the outdoor unit are forced open, allowing the refrigerant to be recovered from all
CAUTION
tubes which are separated by solenoid valves. If this work is not performed, it will not
be possible to recover all of the refrigerant at the refrigerant recovery device. Be sure
to perform this step.
(7) Open both Hi- and Lo-side valves on the manifold gauge valves, and recover the refrigerant remaining in the
outdoor unit. After that, measure the amount of recovered refrigerant.
NOTE
To determine the completion of refrigerant recovery, follow the instructions that came with the refrigerant recovery unit.
High-pressure outlet port
(for ø7.94mm-dia connector)
Indoor unit
Low-pressure outlet port
(for ø7.94mm-dia connector)
Gas tube service port
(for ø7.94mm-dia connector)
Liquid tube service port
(for ø7.94mm-dia connector)
Fig. 10
3 - 17
Mini VRF SYSTEM
Outdoor Unit Repair Procedures
Manifold gauge
Lo
Connect from here to
refrigerant recovery unit
Refrigerant
recovery
cylinder
Measuring scale
3
Hi