Hitachi RAS-2-HVNP Service Manual page 90

3. Piping work and refrigerant charge
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 and W calculated in step 1 and step 2 into the following formula:
1 2
System example (W) =
• 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:
System example (W) =
C: Compensation value (kg) (Refer to the following table)
RAS-8HN(P/C)E
RAS-10HN(P/C)E
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
The total refrigerant charge of this system is calculated by the following formula:
System example (W ) =
TOT
W is the outdoor unit refrigerant charge before shipment explained before, and it's shown in its specific table.
0
Finally, record the refrigerant charge quantity in order to facilitate maintenance and servicing activities.
76
W = W + W
1 2
+
W = W + W - C
1 2
+
Model
RAS-12HN(P/C)
W = W + W
TOT 0
+
Total additional charge W
Total ref. charge of this system
Date of ref. charge work
Year
Month
SMGB0079 rev.0 - 01/2013
= kg
– =
Compensation value (C (kg))
(kg))
TOT
= kg
Day
kg
1.6
2.0
2.0
kg
kg