Mitsubishi Electric CITY MULTI PUHY-P108 Service Handbook page 73

[ II Restrictions ]
(3) Size of the pipe that fits the sub BC controller ports
P72-P234 models
Main BC controller
*1
Reducer
(Standard
supplied parts)
Indoor unit
P18 model or below
The ports of the BC controller accommodates the pipes on P24-P54 models of indoor units. To connect other types of
indoor units, follow the procedure below.
1) To connect P06-P18 models of indoor units use the reducer that is supplied with the BC controller.
2) To connect P72 or P96 models of indoor units (or when the total capacity of indoor units exceeds P55), use a junc-
tion pipe kit (model name: CMY-R160J) and merge the two nozzles.
3) To connect multiple indoor units to a port (or to a junction pipe)
Maximum total capacity of connected indoor units: P54 or below (in a system with a junction pipe: P96 or below)
Maximum number of connectable indoor units: 3 units
Refrigerant pipe selection (size of the pipes in sections A and B in the figure above): Select the proper size pipes
based on the total capacity of the downstream indoor units, using the table below as a reference.
Total capacity of indoor units
P54 or below
P55-P72
P73-P96
*1. Use the pipe that is supplied.
Operation
On the BC controller
side
Connection: brazed connection
*2
Junction pipe kit
Sub BC controller
(Model name:
CMY-R160-J)
(Optional accessory)
Indoor unit Indoor unit
P24-P54 models P72-P96 models
Liquid pipe
ø9.52 [3/8"]
Total capacity of the
indoor units that are High-pressure side
connected to the BC
controller in question
P72 model or below ø15.88 [5/8"]
(Brazed connection)
P73-P108 models
ø19.05 [3/4"]
(Brazed connection)
P109 model or above
- 64 -
Branch joint (Model name:CMY-Y102S-G)
(Optional accessory
for use with the Y series
of City Multi)
A B
Indoor unit Indoor unit
Maximum of 3 units per port
Total capacity of P54 or below
(All units connected to the same port
must be in the same operating mode.)
Pipe sections
Low-pressure side
(gas) (gas)
ø19.05 [3/4"]
(Brazed connection)
ø22.2 [7/8"]
(Brazed connection)
ø28.58 [1-1/8"]
(Brazed connection)
Indoor unit
Unit: mm [in]
Gas pipe
ø15.88 [5/8"]
ø19.05 [3/4"]
*1
ø22.2 [7/8"]
Unit: mm [in]
Liquid pipe side
ø9.52 [3/8"]
(Brazed connection)
ø12.7 [1/2"]
(Brazed connection)