Specifications

RXYQQ8~20T7Y1B
VRV IV System Air Conditioner
4P345099-1 – 2013.04
Installation and operation manual
15
Increase the pipe size as follows:
9.5 → 12.7; 12.7 → 15.9; 15.9 → 19.1; 19.1 → 22.2; 22.2 →
25.4
(3)
; 28.6 → 31.8
(3)
; 34.9 → 38.1
(3)
Example: unit 8: b+c+d+e+f+g+p≤90 m and b+c+d+e+f+g
>40 m; increase the pipe size of b, c, d, e, f, g.
c. When the piping size is increased (step b), the piping length has
to be counted as double (except for the main pipe and the pipes
that are not increased in pipe size).
The total piping length has to be within limitations (see table
above).
Example:
a+b*2+c*2+d*2+e*2+f*2+g*2+h+i+j+k+l+m+n+p ≤ 300 m.
d. The piping length difference between the nearest indoor from
first branch to the outdoor unit and farthest indoor to the outdoor
unit is ≤40 m.
Example:
The farthest indoor unit 8. The nearest indoor unit 1 →
(a+b+c+d+e+f+g+p)–(a+h)≤40 m.
9.6. Multi system piping installation
 Front connection
Remove the front plate knock out holes to connect (see figure
below).
 Bottom connection
Remove the knock out holes on the bottom frame and route the
piping under the bottom frame (see figure below).
9.6.1. Precautions when connecting piping between outdoor
units (multiple outdoor unit system)
 To connect the piping between outdoor units, an optional multi
connection piping kit BHFQ22P1007/1517 is always required.
When installing the piping, follow the instructions in the
installation manual that comes with the kit.
 Only proceed with piping work after considering the limitations
on installing listed here and in the chapter "10.2. Connecting the
refrigerant piping" on page 17 always referring to the installation
manual delivered with the kit.
9.6.2. Possible installation patterns and configurations
 The piping between the outdoor units must be routed level or
slightly upward to avoid the risk of oil retention into the piping.
1 To indoor unit
2 Piping between outdoor units
Prohibited patterns: change to pattern 1 or 2.
1 To indoor unit
2 Piping between outdoor units
 To avoid the risk of oil retention to the outmost outdoor unit,
always connect the stop valve and the piping between outdoor
units as shown in the 4 correct possibilities of the figure below.
Prohibited patterns: change to pattern 1 or 2.
1 To indoor unit
2 Oil collects to the outmost outdoor unit
Change to configuration as in figures below
1 To indoor unit
2 Oil collects to the outmost outdoor unit when the system
stops
Correct configuration
1 To indoor unit
 If the piping length between the outdoor units exceeds 2 m,
create a rise of 200 mm or more in the gas line within a length of
2 m from the kit.
If ≤2m
1 To indoor unit
2 Piping between outdoor units
If >2 m
1 To indoor unit
2 Piping between outdoor units
(3) If available on the site. Otherwise it cannot be increased.
Pattern 1 Pattern 2
2
1
1
1
2
1
2
2
1
1
2
2
1
1
222
1
222
1
2
1
2
1
2
1
1
1
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1
2
P
1
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PP PP

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