Standard Multi-Outdoor-Unit Combinations ≤20 Hp And Free Multi-Outdoor-Unit Combinations - Daikin VRV 5 REYA8A7Y1B Installer And User Manual

18 | Piping installation
18.1.9 Standard multi-outdoor-unit combinations ≤20 HP and free multi-outdoor-unit
combinations
Connection with only VRV DX indoor units
a
H1
a Outdoor unit
b VRV DX indoor unit
c Branch selector (BS)
d VRV DX indoor unit (duct)
e VRV DX indoor unit (large duct)
Installer and user reference guide
88
Longest pipe after the first branch or
multi BS unit (B1+C1, B2+C2, B1+C3,
B1+D+C4)
In case of a multi-outdoor setup:
longest pipe from the outdoor unit to
the last multi-outdoor piping branch (E)
Total pipe length
(a)
If the equivalent piping length is more than 90 m, size up the main liquid piping according
to "18.1.4 To select the piping
(b)
If the height difference between indoor units (=H2) is between 15 and 30 m, then the
allowable maximum length of the longest pipe is limited to 120/165 m (actual/equivalent).
(c)
The limitation can be extended to 90 m if the following conditions are met:
• The piping length between all indoor units and the BS unit is ≤40 m.
• Size-up:
→ It is required to size-up the liquid piping between the first branch kit or BS unit and the last
branch kit or last BS unit.
→ It is also required to size-up the liquid piping downstream of the BS unit if the last refrigerant
branch kit is located downstream of the BS unit.
→ It is not required to size-up the liquid piping between the BS unit and indoor units.
→ If the increased pipe size is larger than the pipe size of the main pipe, also increase the size of the
main pipe.
• In case of size-up of the liquid piping, double its length in the calculation of the total piping length.
Make sure the total piping length is within limitations.
• The piping length difference between the nearest indoor unit to the outdoor unit and the farthest
indoor unit to the outdoor unit is ≤40 m.
H3
E
A
b b
Pipe
size" [ 4 81].
c
B2
d
c
D
B1
d
C1
C3
e
Maximum length (actual/equivalent)
(c)
40 m/—
10 m/13 m
1000 m/—
C2
c
H2
C4
d
REMA5+REYA8~20A7Y1B
VRV 5 heat recovery
4P687640-1 – 2022.07