Mitsubishi Electric HP120TNU-A Service Handbook page 74

[2-10 Restrictions on Refrigerant Pipes ]
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
Branch joint: Use CMY-Y102SS-G2, CMY-Y102LS-G2 (optional accessory).
(3) Size of the pipe that fits the sub BC controller ports (A, B): 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
Main BC controller side
HWE18220_GB
Operation
Total capacity of indoor
units connected to down-
stream BC controller
- P72
P73 - P108
P109 - P126
P127 - P144
P145 - P180
P181 - P234
P235 - P288
P289 - P360
P361 -
Liquid pipe
ø9.52 [3/8"]
ø9.52 [3/8"]
ø9.52 [3/8"]
Pipe sections
High-pressure side Low-pressure side
(gas)
ø15.88 [5/8"] ø19.05 [3/4"]
(Brazed connection) (Brazed connection)
ø22.2 [7/8"]
(Brazed connection)
ø19.05 [3/4"]
(Brazed connection)
ø22.2 [7/8"] ø28.58 [1-1/8"]
(Brazed connection) (Brazed connection)
ø28.58 [1-1/8"] ø34.93 [1-3/8"]
(Brazed connection) (Brazed connection)
ø41.28 [1-5/8"]
(Brazed connection)
ø34.93 [1-3/8"]
(Brazed connection)
Unit : mm [inch]
Gas pipe
ø15.88 [5/8"]
ø19.05 [3/4"]
ø22.2 [7/8"]
Unit : mm [inch]
Liquid pipe side
(gas)
ø9.52 [3/8"]
(Brazed connection)
ø12.7 [1/2"]
(Brazed connection)
ø15.88 [5/8"]
(Brazed connection)
ø19.05 [3/4"]
(Brazed connection)
chapter 2 -
45