Refrigerant Piping Work - Mitsubishi Electric CITY MULTI Series Installation Manual

1. Size of BC controller's end connection piping
[Fig. 5.2.2]
BC CONTROLLER/MAIN BC CONTROLLER
Unit model Model name
(BC CONTROLLER)
PURY-P72
CMB-P104NU-G1
CMB-P105NU-G1
CMB-P106NU-G1
PURY-P96
CMB-P108NU-G1
CMB-P1010NU-G1
CMB-P1013NU-G1
PURY-P120
CMB-P1016NU-G1
PURY-P144
PURY-P168 (MAIN BC
CONTROLLER)
CMB-P108NU-GA1
PURY-P192
CMB-P1010NU-GA1
CMB-P1013NU-GA1
PURY-P216 CMB-P1016NU-GA1
PURY-P240
(MAIN BC
PURY-P264
CONTROLLER)
CMB-P108NU-HA1
CMB-P1010NU-HA1
PURY-P288
CMB-P1016NU-HA1
Indoor unit side
A B
C
G
*2
D
*1
E
E
F
24-54 72-96
A To outdoor unit (MAIN BC CONTROLLER)
B End connection (brazing)
C BC controller (MAIN BC CONTROLLER / SUB BC CONTROLLER)
D Reducer (accessory)
F Less than 18
G Combined piping kit (Model name: CMY-R160-J1)
H Twinning pipe (Model name: CMY-Y102S-G2)
I Up to three units for 1 branch hole; total capacity: below 30 (but same in cooling/heat-
ing mode)
The size of BC controller's branch piping is for 63 to 140 type indoor units.
Therefore, if you want to connect indoor units other than the above, connect pip-
ing following the procedures below.
*1. For connecting 06 to 18 type indoor units
Connect indoor units using the reducers supplied with BC controllers.
Note:
Use only the flare nuts supplied with the BC controller.
*2. To connect a unit with a capacity of higher than 31.
After combining two branches using an optionally available piping kit
(CMY-R160-J1), connect indoor units.
*3. Connection of plural indoor units with one connection (or joint pipe)
• Total capacity of connectable indoor units: Less than 30 (Less than 96 with
joint pipe)
• Number of connectable indoor units: Maximum 3 Sets
• Twinning pipe: Use the twinning pipe for CITY MULTI Y Series (CMY-Y102S-
G2)
• Selection of refrigerant piping
Select the size according to the total capacity of indoor units to be installed
downstream.
Total capacity of indoor units
Below 54
55 to 72
73 to 96
10
High pressure Low pressure
side (mm [in]) side (mm [in])
ø15.88 [5/8] ø19.05 [3/4]
(Brazing) (Brazing)
ø22.2 [7/8]
(Brazing)
ø19.05 [3/4]
(Brazing)
ø25.4 [1]
(Brazing)
ø22.2 [7/8]
(Brazing)
ø28.58 [1-1/8]
(Brazing)
ø28.58 [1-1/8]
(Brazing)
ø34.93 [1-3/8]
(Brazing)
ø9.52 [3/8] ø15.88 [5/8]
(Flare) (Flare)
H
E
E E E
I
*3
E Indoor unit
(Unit: mm [in])
Liquid line Gas line
ø15.88 [5/8]
ø9.52 [3/8] ø19.05 [3/4]
ø22.2 [7/8]
SUB BC CONTROLLER
Total capacity of
Model name
indoor units
When a system that has more than 16 branching points, use BC controllersì
(main and sub) to connect the pipes.
below 72
73-108
109-126
CMB-P104NU-GB1
CMB-P108NU-GB1 127-144
CMB-P1016NU-HB1
145-168
2. Connecting to out side pipes
• For PURY-P72, 96, 120, 144, 168, 192, 216, 240, 264, 288
[Fig. 5.2.3]
High pressure/low pressure piping diagram
C
A Connection pipe of outdoor unit (Low pressure)
B Connection pipe of outdoor unit (High pressure)
ø
C Drain piping (O.D. 32mm [1-1/4 in])
D Connection pipe of indoor unit (Liquid)
E Connection pipe of indoor unit (Gas)
Note:
Be sure to use non-oxidative brazing.

5.3. Refrigerant piping work

After connecting the refrigerant pipes of all indoor and outdoor units with the out-
door units' stop valves remained fully closed, evacuate vacuum from the outdoor
units' stop valve service ports.
After completing the above, open the outdoor units' stop valves. This connects
the refrigerant circuit (between outdoor and BC controller) completely.
How to handle stop valves is described on each outdoor unit.
Notes:
• Before tightening the flare nut, apply refrigerating machine oil lightly
over the valve flare surface and its seating surface.
• Use two wrenches for pipe connection.
• After pipe connection, be sure to check that there is no gas leakage,
using a leak detector or soap-and-water solution.
• Before brazing the refrigerant piping, always wrap the piping on the main
body, and the thermal insulation piping, with damp cloths to prevent
heat shrinkage and burning the thermal insulation tubing. Take care to
ensure that the flame does not come into contact with the main body itself.
• Do not use leak-detection additives.
Warning:
Do not mix anything other than the specified refrigerant (R410A) into the
refrigerating cycle when installing or moving. Mixing air may cause the
refrigerating cycle to reach abnormally high temperature, resulting in burst
pipes.
High pressure Low pressure (gas)
(gas) side (mm [in]) side (mm [in])
ø15.88 [5/8] ø19.05 [3/4]
(Brazing) (Brazing)
ø22.2 [7/8]
(Brazing)
ø19.05 [3/4]
(Brazing)
ø28.58 [1-1/8]
(Brazing)
ø22.2 [7/8]
(Brazing)
ø9.52 [3/8] ø15.88 [5/8]
(Flare) (Flare)
*1 Use the supplied pipe.
D
A
B
E
Liquid side
(mm [in])
ø9.52 [3/8]
(Brazing)
ø12.7 [1/2]
(Brazing)
ø15.88 [5/8]
(Brazing)
(Unit: mm [in])