15
G
B
9.2. Refrigerant piping system
Connection example
[Fig. 9.2.1]
(P.3, 4)
Outdoor model
High-pressure side
Low-pressure side
Total capacity of indoor units
Liquid pipe
Gas pipe
High-pressure gas pipe
Low-pressure gas pipe
Liquid pipe
Model number
Outdoor twinning kit
A
Outdoor unit
B
BC controller (standard)
C
BC controller (main)
D
BC controller (sub)
E
Indoor unit (15 ~ 80)
F
Indoor unit (100 ~ 250)
G
Outdoor twinning kit
*1 The pipe sizes listed in columns A1 to A2 in this table correspond to the sizes
for the models listed in the unit 1 and 2 columns. When the order of unit 1 and
2 is changed, make sure to use the appropriate pipe size for the model.
Precautions for outdoor unit combinations
Refer to [Fig. 9.2.2] for the positioning of twinning pipes.
[Fig. 9.2.2]
(P.5)
<A> The piping from the outdoor units to twinning pipe must be made to slope
downwards the twinning pipe. (high-pressure side only)
<B> Slope of twinning pipes (high-pressure side only)
Make sure the slope of the twinning pipes are at an angle within ±15° to the
ground.
If the slope exceeds the speci
Þ
ed angle, the unit may be damaged.
<C> Pipe connection example
The distributor on the low-pressure side must be placed in the outdoor
unit that has a larger capacity index of the two, regardless of the relative
positions of the outdoor units or their addresses.
(If outdoor units that have the same capacity are used in combination, the
distributor can be placed in either outdoor unit.)
If the distributor is placed in the outdoor unit that has a smaller capacity,
refrigerant will not be properly distributed and compressor failure may result.
A
Downward slope
B
Upward slope
C
BC controller
D
Twinning pipe
E
Slope of the twinning pipe is at an angle within ±15° to the ground
F
Twinning pipe (low-pressure side)
G
Twinning pipe (high-pressure side)
H
On-site piping (low-pressure connecting pipe: between outdoor units)
I
On-site piping (low-pressure main pipe: to BC controller)
J
On-site piping (high-pressure main pipe: to BC controller)
K
Straight run of pipe that is 500 mm or more
10. Additional refrigerant charge
At the time of shipping, the outdoor unit is charged with refrigerant.
This charge does not include the amount needed for extended piping and
additional charging of each refrigerant line will be required on site. In order that
future servicing may be properly provided, always keep a record of the size and
length of each refrigerant line and the amount of additional charge by writing it in
the space provided on the outdoor unit.
10.1. Calculation of additional refrigerant
charge
Calculate the amount of additional charge based on the length of the piping
extension and the size of the refrigerant line.
Use the table below as a guide for calculating the amount of additional
charging and then charge the system accordingly.
If the calculation results in a fraction of less than 0.1 kg, round up to the next
0.1 kg. For example, if the result of the calculation was 27.73 kg, round the
result up to 27.8 kg.
•
•
•
<Additional charge>
Additional refrigerant
charge
=
High-pressure
pipe size
Total length of ø28.58
×0.36
+
High-pressure
pipe size
Total length of ø22.2
×0.23
+
High-pressure
pipe size
Total length of ø19.05
×0.16
+
High-pressure
pipe size
Total length of ø15.88
×0.11
+
Liquid Piping Size
Total length of ø15.88
×0.2
(kg)
(m)×0.36(kg/m)
(m)×0.23(kg/m)
(m)×0.16(kg/m)
(m)×0.11(kg/m)
(m)×0.2(kg/m)
+
Liquid Piping Size
Total length of ø12.7
×0.12
+
Liquid Piping Size
Total length of ø9.52
×0.06
+
Liquid Piping Size
Total length of ø6.35
×0.024
(m)×0.12(kg/m)
(m)×0.06(kg/m)
(m)×0.024(kg/m)
+
Total Outdoor Unit
Model Name
BC controller
(Standard/Main)
Per Unit
+
BC controller
(Main) HA-type
+
BC controller
(Sub) Total Units
BC controller
(Sub) Per Unit
+
Total Capacity of
Connected Indoor Units
Per Indoor
Unit
~80
2.0kg
P200
2.0kg
2.0 kg
1
1.0 kg
81~160
2.5kg
P250
3.0kg
161~330
3.0kg
P300
2
2.0 kg
331~390
3.5kg
P350
4.5kg
391~480
4.5kg
P400
481~630
5.0kg
P450
5.0kg
631~710
6.0kg
P500
6.0kg
711~800
8.0kg
P550
801~890
9.0kg
P600
891~1070
10.0kg
P650
7.5kg
1071~1250
12.0kg
P700
1251~
14.0kg
P750
9.0kg
P800
<Example>
Indoor
1: 80
A: ø28.58
40 m
a: ø9.52
10 m
At the
conditions
below:
2: 250
B: ø9.52
10 m
b: ø9.52
5 m
3: 32
C: ø9.52
20 m
c: ø6.35
5 m
4: 40
D: ø9.52
5 m
d: ø6.35
10 m
5: 32
E: ø9.52
5 m
e: ø6.35
5 m
6: 63
F: ø22.2
3 m
f: ø9.52
5 m
G: ø19.05
1 m
The total length of each liquid line is as follows:
ø28.58: A = 40 m
ø22.2: F = 3 m
ø19.05: G = 1 m
ø9.52: C + D + E + a + b + f = 50 m
ø6.35: c + d + e = 20 m
Therefore,
<Calculation example>
Additional refrigerant charge
= 40
u
0.36 + 3
u
0.23 + 1
u
0.16 + 50
u
0.06 + 20
u
0.024 + 2 + 2 + 5
= 27.8 kg
