Hitachi UTOPIA RAS-4HVRP2E - Refrigerant Charge before Shipment (W (Kg)); Calculation Method for the Additional Refrigerant Charge

3 Piping work and refrigerant charge
Refrigerant charge
SMGB0136 rev.0 - 07/2021
61
3
3.4.3 Refrigerant charge before shipment (W
0
(kg))
W
0
is the outdoor unit refrigerant charge before shipment explained before, and it’s shown in the following table:
UTOPIA series 2
Model
Refrigerant charge before
shipment (W
0
(kg))
Additional refrigerant charge
(P) (g/m)
Maximum additional charge
(kg)
RAS-3HVRC2 1.7 30 0.9
RAS-4HVR(C/P)2E
3.0 45 2.9
RAS-5HVR(C/P)2E
RAS-6HVR(C/P)2E
RAS-4HR(C/P)2E
RAS-5HR(C/P)2E
RAS-6HR(C/P)2E
RAS-4HVN(C/P)2E
3.2 60 3.9
RAS-5HVN(C/P)2E
RAS-6HVN(C/P)2E
RAS-4HN(C/P)2E
RAS-5HN(C/P)2E
RAS-6HN(C/P)2E
3.4.4 Calculation method for the additional refrigerant charge
Calculate the additional refrigerant charge amount according to the following steps:

Step 1: Additional refrigerant charge calculation for liquid piping (W
1
(kg))
Outdoor units have been charged with refrigerant for 20 m of actual piping length: In systems with longer actual piping
length, an additional refrigerant charge is required.
Use the following formula:
W
1
= (TL-20) x P
TL: Total piping length (m)
P: Additional refrigerant charge (kg/m) (Refer to the “3.4.3 Refrigerant charge before shipment (W
0
(kg))” chapter)
! CAUTION
Do not exceed the allowed maximum additional charge.

Step 2: Charging work
Charge refrigerant into the system according to the instructions in the Service Manual.

Step 3: Total refrigerant charge of the system (W
TOT
(kg))
The total refrigerant charge of this system is calculated by the following formula:
W
TOT
= W
0
+ W
1
System example (W
TOT
) = + = kg