Panasonic U-72MF2U9 Service Manual page 79

7. Charging Compressor Oil
7. Charging Compressor Oil
(2) Charging compressor oil into oil-charging tank
Connect a piece of pipe to the lower valve and then insert the other end deeply into the bottom of the oil con-
tainer. Make sure you avoid letting any air be sucked into the tube. Next, run the vacuum pump and open the
manifold gauge valves, then open the upper and lower valves to begin charging oil into the charging tank.
Vacuum pump
When the predetermined amount of oil has been charged into the oil-charging tank, immediately close the lower
valve. Next, run the vacuum pump until the system pressure reaches lower than -14.7 psig { -101 kPa, 5 Torr }.
Close the upper valve and then, stop the vacuum pump.
Do this operation quickly because compressor oil easily absorbs moisture from
CAUTION
the air.
(3) Charging compressor oil into outdoor unit
Connect the lower valve to the low-pressure outlet (with Schrader-type push-to-release valve) in the outdoor
unit to be oil-charged, and then connect the high-pressure outlet (with push-to-release valve) to the upper valve
via the manifold gauge valves (at Hi-pressure gauge side). In addition, connect the suction tube service port
(with push-to-release valve) to the DPR (Discharge Pressure Regulator). Carry out the connection work quickly
to avoid letting air enter.
•
CAUTION
•
Type: 72, 96
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)
Manifold
gauge
Lo Hi
Upper side
valve
Lower side
valve
The hoses may be subject to internal pressure from the refrigerant inside the out
door unit. A Schrader-type push-to-release valve is provided at each connection
port.
Since the DPR valve opens at pressures of 362.6 psi (2.5 MPa) and above, be sure to
connect the DPR to the suction tube service port (low-pressure side).
Outdoor Unit Repair Procedures
Outdoor Unit Repair Procedures
Close → Open
Close → Open
Upper side
valve
Manifold
gauge
Lo Hi
Lower side
valve
Discharge tube service port
(for ø5/16" (ø7.94mm)-
dia connector)
Suction tube service port
(for ø5/16" (ø7.94mm)-
dia connector)
2 - 15
2WAY VRF SYSTEM
3WAY VRF SYSTEM
Fig. 10
DPR
Close
Close
Fig. 11-a
1
2
3
4
5
6
7
8
9