Refrigerant Charge - Mitsubishi Electric BRANCH BOX PAC-MK52BCB Manuel D'installation

7. Installing refrigerant piping
C
Fig. 7-3
AB
DE
F
Fig. 7-4
F
G
J
H
Fig. 7-6
1.5 m or less
J
H
Fig. 7-8
8
B
A
D
E
Check if there is any
foreign object inside.
Fig. 7-5
(mm)
Fig. 7-7
Support
Pipe cover
(1) Remove the rubber caps from the outdoor unit side connection pipe A and B.
(2) After brazing D to the liquid pipe side and E to the gas pipe of the refrigerant pipe
connected to the outdoor unit side, braze the branch box to connect. (Fig. 7-3, 7-4)
When installing the unit on a wall, do not braze the joint pipe to the unit fi rst. Doing
so will make fi lling the gap with fi ller metal diffi cult, resulting in a refrigerant leak
when brazing the refrigerant pipe.
(3) When brazing in succession, conduct the next brazing once the welded section
has cooled down to room temperature. Failure to do so will cause the insulation
material or the unit to melt causing condensation.
Remove the copper cap of C, and braze the refrigerant piping connected to the
indoor unit. (Fig. 7-3)
(4) When the indoor unit is not connected, do not remove the copper cap of C, or
refrigerant leaks.
(5) After cutting piping or unsoldering brazed piping or copper caps,ensure to clean
away any foreign object
(i.e., brazing material, cutting chips) so as to prevent entry of any foreign object
into the piping. Failure to do so may cause malfunction of the outdoor compres-
sor, and the like. (Fig.7-5)
A To outdoor unit connection pipe.(Liquid)
B To outdoor unit connection pipe.(Gas)
C To indoor unit connection pipes
D Joint pipe(Liquid) (3.1 Accessories No.⑩)
E Joint pipe(Gas) (3.1 Accessories No.⑪)
Note:
Optional joint pipes are to some indoor units.
Please refer to the installation manual of outdoor unit and indoor unit for
details.
(6) Press the pipe covers 3 and 5 on the liquid piping against the unit and wrap to
hold in place. (Fig. 7-6)
(7) Press the pipe covers 4 and 6 on the gas piping against the unit and wrap to
hold in place. (Fig. 7-6)
(8) Apply the supplied bands 9 at a position 10 - 20 mm from each end of the pipe
covers (3456). (Fig. 7-7)
(9) If the indoor unit is not connected, fi t the supplied pipe covers (with caps, 7 and
8) to the branch box refrigerant piping connections against the unit to prevent
condensation dripping from the pipes. (Fig. 7-7)
(10) Clamp the pipe covers (78) in place with the supplied bands 9. (Fig. 7-7)
F Band (3.1 Accessories No.9)
G Pipe covers (3.1 Accessories No.3456)
H Refrigerant piping
J Thermal insulation for refrigerant piping

► Refrigerant charge:

Refer to the installation manual of the outdoor unit.
Use only R410A refrigerant (use of other refrigerants may cause troubles).
Caution:
To avoid excessive strain on the branch box, support the piping with one or
more support(s) 1.5 m or less from the branch box.
Refer to Fig. 7-8 as an example.
H Refrigerant piping
J Thermal insulation for refrigerant piping