Mitsubishi Electric CITY MULTI CMB-P-V-J Manuel D'installation page 12

Piping length and height between indoor unit and BC controller
100
90
80
70
60
50
40
30
20
10
0 5
Height difference between
the main BC controller and indoor unit (m)
Fig. 1
Fig. 2
BC
Sub
Fig. 2
BC
Fig. 1 Fig. 1
Indoor Indoor
unit unit
12
100
90
80
*3
70
60
50
40
30
20
10
10 15 0
the main BC controller and indoor unit (m)
Fig. 2
Sub
BC
Fig. 1
Indoor
unit
5 10 15
Height difference between
*3 When the piping length or the height difference exceeds the restriction
specified in Fig. 1, connect a sub BC controller to the system. The
restriction for a system with a sub BC controller is shown in Fig. 2.
When a given system configuration falls within the shaded area in Fig.
2, increase the size of the high-pressure pipe and the liquid pipe
between the main and sub BC controller by one size. When using P32,
P40, P50, P100, or P125 model of indoor units, increase the size of the
liquid branch pipe between the sub BC controller and indoor unit by
one size.
When using P140 or larger model of indoor units, the restriction shown
in Fig. 1 cannot be exceeded.