Mitsubishi Electric PQHY-P120THMU-A, Service Handbook

Page: 81 / 414

[
II
Restrictions ]
- 72 - HWE09080 GB
(3) Size of the pipe that fits the sub BC controller ports
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 the units between the P36 and P96 models of indoor units (or when the total capacity of indoor units is P31
or above), use a junction pipe kit and merge the two nozzles.
3) To connect multiple indoor units to a port (or to a junction pipe)
Œ
Maximum total capacity of connected indoor units: P54 or below (in a system with a junction pipe: P96 or below)
Œ
Maximum number of connectable indoor units: 3 units
Œ
Branch joint: Use CMY-Y102S-G2 (optional accessory).
Œ
Refrigerant pipe selection (size of the pipes in sections A and B in the figure above): Select the proper based on the total
capacity of the downstream indoor units, using the table below as a reference.
Select the proper size pipes for the main unit based on the total capacity of the indoor units that are connected to both sub
BC controllers. Select the proper size pipes for the sub controller side based on the total capacity of the indoor units that are
connected to the sub controller.
Unit : mm [inch]
Total capacity of indoor units Liquid pipe Gas pipe
P54 or below ø9.52 [3/8"] ø15.88 [5/8"]
P55 - P72 ø9.52 [3/8"] ø19.05 [3/4"]
P73 - P96 ø9.52 [3/8"] ø22.2 [7/8"]
Unit : mm [inch]
Operation Pipe sections
High-pressure side
(liquid)
Low-pressure side
(gas)
Liquid pipe side
Total capacity of the in-
door units that are con-
nected to the BC
controller
On the BC controller
side
P72 model or below
ø15.88 [5/8"]
(Brazed connection)
ø19.05 [3/4"]
(Brazed connection)
ø9.52 [3/8"]
(Brazed connection)
P73 - P108
ø19.05 [3/4"]
(Brazed connection)
ø22.2 [7/8"]
(Brazed connection)
P109 - P126
ø28.58 [1-1/8"]
(Brazed connection)
ø12.7 [1/2"]
(Brazed connection)
P127 - P144
ø22.2 [7/8"]
(Brazed connection)
P145 - P168
ø15.88 [5/8"]
(Brazed connection)
A B
Indoor Indoor Indoor
P18 model or below P24-P54 models P72 or P96 model
*2
Junction pipe kit
(Model name:
CMY-R160-J)
(Optional accessory)
BC controller (sub)
To Main BC controller
Connection: Brazed connection
*1
Reducer
(Standard supplied parts)
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.) 3*
Indoor Indoor Indoor
Branch joint (Model name:CMY-Y102S-G2)
(Optional
accessory)