Hitachi RAS-10HRNM, Service Manual, Page: 84 / 482

The possible combination between Outdoor Unit and Indoor Unit are the following:
Single System Twin System
L= A + the longest of B & C
Triple System Quad System
L= A + the longest of B, C & D
L= A + (the longest of B + the longest of D & E) & (C + the
longest of F & G)
N O T E
• L & H are the length & height indicated in the above chart.
• For twin, the length is the distance between the outdoor unit and the farthest indoor unit.
• Piping length after branch pipe (B,C & D):
1 After branch pipe B,C & D, the pipe length should be shorter than 10 m.
2 All branch pipe, B, C & D (it depend of case), should be balanced.
Twin Triple Quad
B & C difference B,C & D difference B-C, B-D, B-E, C-D, C-E, D-E
≤
8 m
≤
6 m
≤
8 m
3.4.3 Refrigerant piping selection
Select the piping connection sizes according to the following procedures
• Between outdoor unit and branch pipe: Select the same pipe connection size as the pipe size of the outdoor unit.
• Between branch pipe and indoor unit: Select the same pipe connection size as the pipe size of the indoor unit.
3 Piping work and
refrigerant charge
76
SMGB0060 rev. 1- 12/2010