6 Installation
Installer and user reference guide
28
RYYQ+RYMQ+RXYQ8~20U7Y1B
VRV IV+ heat pump
4P546228-1 – 2018.09
(a)
ONLY required for RYYQ8~20 models, NOT for
RXYQ8~54 and RYYQ22~54.
▪
Parameter C:
Parameter C
(a)
Model
CR≥100%
CR<100%
If
Then
If
Then
8 HP
N≥4
C=N×0.1 kg
N<4
C=0 kg
C=0 kg
10 HP
N≥5
N<5
12 HP
N≥6
N<6
14 HP
N≥7
N<7
16 HP
N≥8
N<8
18 HP
N≥9
N<9
20 HP
N≥10
N<10
(a)
In case of a multi-outdoor-unit system, add the sum of the
individual outdoor unit charge factors.
CR
Total indoor unit capacity connection ratio
N
Number of VRV DX and RA DX indoor units connected to
the outdoor unit
Parameter C – Example with multiple outdoor units:
550
200
300
125
125
125 125 50
500
12 HP
8 HP
#
Action
1
Determine the connection ratio:
▪ Total outdoor unit capacity class = 500
▪ Total indoor unit capacity class = 550
=> CR≥100%
2
Determine parameter C:
▪ N=5
▪ 8 HP: N≥4 => C1=N×0.1=5×0.1 kg
▪ 12 HP: N<6 => C2=0 kg
=> C=C1+C2=0.5 kg
Metric piping.
When using metric piping, replace the weight factors
in the formula by the ones from the following table:
Inch piping
Metric piping
Piping
Weight factor
Piping
Weight factor
Ø6.4 mm
0.022
Ø6 mm
0.018
Ø9.5 mm
0.059
Ø10 mm
0.065
Ø12.7 mm
0.12
Ø12 mm
0.097
Ø15.9 mm
0.18
Ø15 mm
0.16
Ø16 mm
0.18
Ø19.1 mm
0.26
Ø18 mm
0.24
Ø22.2 mm
0.37
Ø22 mm
0.35
Connection ratio requirements.
When selecting indoor units, the
connection ratio must comply with the following requirements. For
more information, see the technical engineering data.
Other combinations than those mentioned in the table are not
allowed.
Indoor
units
Total
CR
(a)
CR per type
(b)
VRV DX
RA DX
LT
Hydrobox
AHU
VRV DX
50~130% 50~130%
—
—
—
Indoor
units
Total
CR
(a)
CR per type
(b)
VRV DX
RA DX
LT
Hydrobox
AHU
VRV DX +
RA DX
80~130%
0~130%
0~130%
—
—
RA DX
80~130%
—
80~130%
—
—
VRV DX +
LT
Hydrobox
50~130% 50~130%
—
0~80%
—
VRV DX +
AHU
50~110% 50~110%
—
—
0~60%
AHU
90~110%
—
—
—
90~110%
(a)
Total CR = Total indoor unit capacity connection ratio
(b)
CR per type = Allowable capacity connection ratio per
indoor unit type
