Additional Refrigerant Charge Calculation For Indoor Unit; Calculation Of Total Additional Refrigerant Charge; Charging Work; Total Refrigerant Charge Of The System - Hitachi RAS-(3-6)HVNC1(E) Service Manual

3 Piping work and
refrigerant charge
Step 2: Additional refrigerant charge calculation for indoor unit (W
When the outdoor unit is combined with indoor units RPI-(8/10)HP allowed (1 unit system combination only), it´s necessary
an additional refrigerant charge (W
needed.
Indoor unit capacity
≥ 8 HP
< 8 HP
Step 3: Calculation of total additional refrigerant charge (W (kg))
a. 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
b. 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)
Model
RAS-8HN(P/C)E
RAS-10HN(P/C)E
RAS-12HN(P/C)
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
W is the outdoor unit refrigerant charge before shipment previous explained, and it's shown in its specific table.
0
Finally, record the refrigerant charge quantity in order to facilitate maintenance and servicing activities.
87
SMGB0087 rev.0 - 12/2013
) = 1kg/unit. For indoor units lower than 8 HP, an additional refrigerant charge it's not
2
W = W
System example (W) =
W = W
+
W
TOT
) =
TOT
Total additional charge W
Total ref. charge of this system
Date of ref. charge work
Year Month
(kg))
2
Additional refrigerant charge (W
+ W
1 2
+ =
+ W - C
1 2
– =
Compensation value (C (kg))
(kg))
TOT
= W + W
0
+ =
kg
kg
Day
(kg))
2
1
0
kg
kg
1.6
2.0
2.0
kg
3