Hitachi RAS-5FSN Installations- Und Betriebshandbuch Seite 24

ADDITIONAL CHARGE OF REFRIGERANT R410A
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15. ADDITIONAL CHARGE OF REFRIGERANT R410A
Additional Charge of Refrigerant R410A
Although refrigerant has been charged into this unit, it is
required that additional refrigerant be charged according to
piping length and indoor units.
A. Determine the additional refrigerant quantity according
to the following procedure, and charge it into the system.
B. Record the additional refrigerant quantity to facilitate
service activities thereafter.
Outdoor Unit
H1 50m (Position of outdoor unit is higher)
H1 40m (Position of outdoor unit is Lower)
Actual Lt 100m
Provide oil trap to gas line at
Equivalent Lt 125m
every Ht meters lift
1. Calculating Method of Additional Refrigerant Charge
(W kg)
Calculate the additional refrigerant charge amount
according to the following method 1.1 to 1.3.
1.1.Additional Refrigerant Charge Calculation for Liquid
Piping (W1 kg)
Calculate the additional refrigerant charge amount for
liquid piping as below and see example for model
RAS-8FSN, and fill in the following table.
Example
Piper Diameter Total Pipe Additional
(mm) Lenght (m) Charge (Kg/m)
22.2 0 0.390
19.05 0 0.280
15.88 0 0.190
12.7 0 0.120
9.53 51 0.07
6.35 5+3+5+3+5+3 0.03
Total Additional Charge Amount for Liquid Pipe (W1) = 4.29 kg
This system (Fill in the following table)
Piper Diameter
(mm)
22.2
19.05
15.88
12.7
9.53
6.35
Total Additional Charge Amount for Liquid Pipe (W1) =
ATTENTION:
Is NOT necessary refrigerant charge for indoor units.
1.2 Determine the number of indoor units which require
the additional refrigerant charge
Outdoor Unit
RAS-5FSN
RAS-8FSN(E)
RAS-10FSN(E)
RAS-16FSN
RAS-20FSN
RAS-24FSN
RAS-30FSN
Outdoor Unit
RAS-8FXNE
RAS-10FXNE
RAS-16FXN
RAS-20FXN
RAS-24FXN
RAS-30FXN
Sub Total
Amount (Kg)
0 x 0.390 = 0
0 x 0.280 = 0
0 x 0.195 = 0
0 x 0.120 = 0
51 x 0.07 = 3.57
24 x 0.03 = 0.72
NOTE:
W is Outdoor Unit refrigerant charge before shipment.
0
Total Pipe Additional
Lenght (m) Charge (Kg/m)
0.390
0.280
0.190
0.120
0.07
0.03
W0 Outdoor Unit Ref.
Charge (Kg)
5.4
8.5
9.5
13.0
19.0
23.0
26.0
W0 Outdoor Unit Ref.
Charge (Kg)
8.5
9.5
19.0
19.0
26.0
26.0
Horse Power W2 Add. Charge (Kg)
0.8 0
1.0 0
1.5 0
2.0 0
2.5 0
3.0 0
4.0 0
8.0 1.0
10.0 1.0
Sub Total
Amount (Kg)
kg