Pumping Out Refrigerant From Outdoot Unit - Panasonic U-72MF2U9 Service Manual

8. Pumping Out Refrigerant from Outdoor Unit
8. Pumping Out Refrigerant from Outdoor Unit
Required equipment and tools:
This work is performed in order to collect the refrigerant from an outdoor unit where repairs (other than compressor
replacement) will be performed into other outdoor units and indoor units, and the refrigerant tube.
8-1. If Remote Controller is Used for Maintenance of Outdoor Unit
(1) See "3. Backup Operation" and perform backup operation.
(2) Connect the manifold gauge valves at the Lo side to the low-pressure outlet port of the outdoor unit to be
repaired. Also connect the refrigerant recovery cylinder to any one of the normal outdoor units at the liquid tube
service port (Schrader-type push-to-release valve). Perform the connection work quickly so that no air is
allowed to enter. (Fig. 14)
* Connecting the refrigerant recovery cylinder is done to prevent pressure from rising excessively during backup
operation by recovering the refrigerant from the outdoor unit to be repaired.
(Measure the weight of the refrigerant and cylinder itself beforehand and provide sufficient safety measures,
such as installing a high-pressure cutout in the circuit.)
The hoses may be subject to internal pressure from the refrigerant inside the outdoor
unit. Check that the manifold gauge valves are fully closed beforehand.
CAUTION
A Schrader-type push-to-release valve is provided at each connection port.
(3) Connect the outdoor unit maintenance remote controller to the RC connector (3P) (BLU) (CN73) on the outdoor
unit control PCB of the outdoor unit to be repaired. Then start a test run of all units.
(Press and hold the
Low-pressure outlet port
(for ø5/16" (ø7.94m)-
dia connector)
Manifold
gauge
Lo Hi
High-pressure
outlet port (for
ø5/16" (ø7.94mm) -
dia connector)
Connect from here to
refrigerant recovery unit
Jumper wire with clips, adjustable wrench, set of manifold gauge valves for the
refrigerant R410A, refrigerant recovery unit, pre-purged refrigerant cylinder for
recovery, flat-head screwdriver, and outdoor unit maintenance remote controller.
(CHECK) button for 4 seconds or longer.)
Faulty outdoor unit
Outdoor Unit Repair Procedures
Outdoor Unit Repair Procedures
Other outdoor unit
2 - 19
2WAY VRF SYSTEM
3WAY VRF SYSTEM
Liquid tube service port
(for ø5/16" (ø7.94mm)-
dia connector)
Refrigerant
recovery
cylinder
Measuring scale
To indoor unit
Fig. 14
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