Hitachi RAS-3-HVNC - Electrical Wiring Connection for the Outdoor Unit

3. Piping work and refrigerant charge
76
SMGB0079 rev.0 - 01/2013
Step 3: Calculation of total additional refrigerant charge (W (kg))
• For all UTOPIA units except RAS-(8-12)HN(P/C)(E)
Put weight W
1
and W
2
calculated in step 1 and step 2 into the following formula:
W = W
1
+ W
2
System example (W) = + = kg
• For UTOPIA units RAS-(8-12)HN(P/C)(E)
In case of RAS-(8-12)HN(P/C)(E), it must be used the following formula:
W = W
1
+ W
2
- C
System example (W) = + – = kg
C: Compensation value (kg) (Refer to the following table)
Model Compensation value (C (kg))
RAS-8HN(P/C)E 1.6
RAS-10HN(P/C)E 2.0
RAS-12HN(P/C) 2.0
C A U T I O N
Donotexceedtheallowedmaximumadditionalcharge
Step 4: Charging work
Charge refrigerant (R410A) into the system according to the instructions in the Service Manual.
Step 5: 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 + W
0
System example (W
TOT
) = + = kg
W
0
is the outdoor unit refrigerant charge before shipment explained before, and it’s shown in its specic table.
Finally, record the refrigerant charge quantity in order to facilitate maintenance and servicing activities.
Total additional charge W
kg
kg
Total ref. charge of this system
Date of ref. charge work
Year
Month
Day