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14 Piping installation
Installation and operation manual
25
RYYQ+RYMQ+RXYQ8~20U7Y1B
VRV IV+ heat pump
4P546220-1C – 2020.10
NOTICE
In case of a multiple outdoor system, turn on the power of
all outdoor units.
NOTICE
Be sure to turn ON the power 6 hours before operation in
order to have power running to the crankcase heater and
to protect the compressor.
NOTICE
If operation is performed within 12 minutes after the indoor
and outdoor units are powered on, the compressor will not
operate before the communication is established in a
correct way between outdoor unit(s) and indoor units.
NOTICE
Before starting charging procedures, check if the
7‑segment display indication of the outdoor unit A1P PCB
is as normal (see
35]). If a
malfunction code is present, see
40].
NOTICE
Make sure all connected indoor units are recognised (see
[1‑10], [1‑38] and [1‑39] in
NOTICE
Close the front panel before any refrigerant charge
operation is executed. Without the front panel attached the
unit cannot judge correctly whether it is operating properly
or not.
NOTICE
In case of maintenance and the system (outdoor unit+field
indoor units) does not contain any refrigerant any
more (e.g., after refrigerant reclaim operation), the unit has
to be charged with its original amount of refrigerant (refer
to the nameplate on the unit) by pre-charging before the
automatic charging function can be started.
14.4.2
About charging refrigerant
Once vacuum drying is finished, additional refrigerant charging can
start.
There are two methods to charge additional refrigerant.
Method
See
Automatic charge
"Step 6a: To automatically charge
refrigerant"
Manual charge
"Step 6b: To manually charge
refrigerant"
INFORMATION
Adding refrigerant using the automatic refrigerant charging
function is not possible when Hydrobox units or RA DX
indoor units are connected to the system.
To speed up the refrigerant charging process, it is in case of larger
systems recommended to first pre-charge a portion of refrigerant
through the liquid line before proceeding with the actual automatic or
manual charging. This step is included in below procedure (see
28]). It can be skipped, but charging will take
longer then.
A flow chart is available which gives an overview of the possibilities
and actions to be taken (see
14.4.3
To determine the additional refrigerant
amount
INFORMATION
For final charge adjustment in the test laboratory, please
contact your local dealer.
NOTICE
The refrigerant charge of the system must be less than
100 kg. This means that in case the calculated total
refrigerant charge is equal to or more than 95 kg you must
divide your multiple outdoor system into smaller
independent systems, each containing less than 95 kg
refrigerant charge. For factory charge, refer to the unit
name plate.
Formula:
R=[(X
1
×
Ø22.2
)×0.37+(X
2
×
Ø19.1
)×0.26+(X
3
×
Ø15.9
)×0.18+
(X
4
×
Ø12.7
)×0.12+(X
5
×
Ø9.5
)×0.059+(X
6
×
Ø6.4
)×0.022]+A+B+C
R
Additional refrigerant to be charged [in kg and rounded off
to 1 decimal place]
X
1...6
Total length [m] of liquid piping size at
Øa
A~C
Parameters A~C (see tables below)
▪
Parameter A:
Parameter A
(a)
Piping length
(b)
CR
A
8 HP
10~14 HP 16~20 HP
≤30 m
50%≤CR≤105%
0 kg
0.5 kg
105%<CR≤130%
0.5 kg
1.0 kg
>30 m
50%≤CR≤70%
0 kg
0.5 kg
70%<CR≤85%
0.3 kg
0.5 kg
1.0 kg
85%<CR≤105%
0.7 kg
1.0 kg
1.5 kg
105%<CR≤130%
1.2 kg
1.5 kg
2.0 kg
(a)
In case of a multi-outdoor-unit system, add the sum of the
individual outdoor unit charge factors.
(b)
Piping length is considered the distance from the outdoor
unit to the farthest indoor unit
CR
Total indoor unit capacity connection ratio
▪
Parameter B:
Parameter B
(a)
RYYQ8~12
RYYQ14
RYYQ16
RYYQ20
1.4 kg
1.7 kg
1.2 kg
2.0 kg
(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: