Connecting pipe size of indoor unit
Capacity rank
Branching section
Indoor unit
007 to 012 type
(3)
connecting
Indoor unit
pipe
015 to 018 type
021 to 048 type
Selection of branching section (Y-shaped branching joint)
Y-shaped
(4)
Branching section
branching
joint
Selection of branching section (Branching header)
Branching
(5)
Branching section
Branching header*
header
* A capacity code up to a maximum of 57 is connectable to one line after branching
from the header.
EN-19
Gas pipe
Liquid pipe
Ø3/8"
Ø1/4"
Ø1/2"
Ø1/4"
Ø5/8"
Ø3/8"
Model name
Y-shape branch joint
RBM-BY55UL
Model name
For 4 branches RBM-HY1043UL
For 8 branches RBM-HY1083UL
Allowable length / height difference of the refrigerant piping
Outdoor unit
Main
pipe
L1
1st branching
section
Height difference
between indoor and
Branching pipe
H1
outdoor units
L3
Equivalent length corresponded to farthest piping after 1st branching
Total extension of pipe (liquid pipe, real length)
Furthest piping length
L (*1)
Piping Length
Max. equivalent length of main pipe
Max. equivalent length of furthest piping from
1st branching Li (*1)
Max. real length of indoor unit connecting pipe
Height between indoor
Height
and outdoor units H1
Difference
Height between indoor units H2
*1 Furthest indoor unit from 1st branch to be named "A".
– 10 –
Branching
L2
Branching pipe
header
a
b
c d
Indoor unit
L
Equivalent length corresponds to farthest piping
Li
f
e
Y-shaped
branching joint
Allowable
value (ft (m))
591 (180)
L1 + L2 + L3 + a + b + c + d + e + f
Real length
328 (100)
Equivalent length
410 (125)
213 (65)
115 (35)
49 (15)
Upper outdoor unit
164 (50)
Lower outdoor unit
131 (40)
49 (15)
Height
difference
between indoor
H2
units
*1
A
Pipes
L1 + L3 + f
L1
L3 + f
a, b, c, d, e, f
EN-20