Hitachi SET FREE-Serie Bedienungsanleitung Seite 52

PIPING WORK AND REFRIGERANT CHARGE
Calculating method of additional refrigerant charge (W kg)

W1
Additional refrigerant charge calculation for liquid piping (W1 kg)
Pipe diameter (mm)
∅28.58
∅25.40
∅22.20
∅19.05
∅15.88
∅12.70
∅9.52
∅6.35
?
n o t e
In the case that the quantity calculated above is less than the minimum quantity indicated in the table below, adopt the quantity in the table below as
the additional refrigerant quantity for piping liquid, regardless of the piping length.
series
Unit Capacity (HP) 8,10
min. additional ref.
Charge of Base Unit
2.0
(kg)
series
Unit Capacity (HP)
5-10
minimum additional
ref. Charge of Base 2.0
Unit (kg)
For combination of the units, adopt the total minimum quantity of each base unit as the minimum additional refrigerant quantity.

W2
Additional refrigerant charge quantity for indoor unit (only for heat pump system) (W2 kg)
The additional refrigerant charge is required depending on the number of connected indoor units. Select the refrigerant quantity from
the following table.
Additional refrigerant charge quantity (kg)
indoor Unit Capacity (HP)
additional refrigerant Charge (kg)
!
C a U t i o n
Only for Heat Recovery System, maximum additional refrigerant charge must not exceed 6.0kg.
number of indoor units x (0.3kg/unit or 0.5kg/unit)
=
42 PMML0479 rev.2 - 02/2018
total piping length (m)
m
m
m
m
m
m
m
m
Total additional charge for liquid piping =
12-18 20-24 26-36 38-42 44-48 50-54 56- 60 62-66 68-72 74- 78 80-84 86-90 92-96
3.0 4.0 6.0 7.0
12,14 16-20 22 24,26 28-32 34,36 38-42 44,46 48,50 52,54 56,58
3.0 4.0 5.0 6.0
0.4 - 1.0
0.3
≤6.0kg
refrigerant amount for 1m pipe
(kg/m)
x 0.67 =
x 0.52 =
× 0.36 =
× 0.26 =
× 0.17 =
× 0.11 =
× 0.056 =
× 0.024 =
fsXnse
8.0 9.0 10.0 11.0
fsXnPe
7.0 8.0 9.0 10.0 11.0
1.5 - 6.0
0.5
additional charge (kg)
12.0 13.0 14.0 15.0
60 62
12.0
13.0 14.0 15.0
16.0
64-72
16.0