Drain Piping - Hitachi CENTRIFUGAL VRF Serie Bedienungsanleitung

DRAIN PIPING

For RASC-(8/10)HNPE units
The additional refrigerant charge for RASC-(8/10)HNPE units
must be calculated by multiplying the total piping length of each
diameter per its calculation factor according to the following
table. The result is the additional refrigerant charge for liquid
piping W .
1
Pipe size (mm)
Ø15.88
Ø12.7
Ø9.52
Ø6.35
(*): For RASC-(8/10)HNPE units ,add 0.030 kg/m (instead of
0.065 kg/m) when there are 5 or more indoor units connected to
the RASC unit.
Step 2: Additional refrigerant charge calculation for
indoor unit (W (kg))
2
When the RASC unit is combined with indoor units RPI-(8/10)
HP, an additional refrigerant charge is required (W
unit. For indoor units lower than 8 HP, an additional refrigerant
charge is not needed.
Indoor unit capacity
≥ 8 HP
< 8 HP
Step 3: Calculation of total additional refrigerant
charge (W (kg))
For RASC-(4-6)HNPE units
Put weight W and W calculated in step 1 and step 2 into the
1 2
following formula:
W = W
System example (W) =
9 DRAIN PIPING

Provision regarding installation place
Drain water sometimes turns to ice. Therefore, avoid draining in an area that people often use because it is slippery.
Install the unit making sure that the drain outlet part is lower (>25mm / <30mm) than the opposite side in order to avoid incorrect
drain discharge.
Floor mounted
Drain pipe
13 PMML0399B rev.1 - 07/2016
Additional refrigerant charge
factor (kg/m)
x 0.19
x 0.12
x 0.065
x 0.065 (*)
) = 1 kg/
2
Additional refrigerant charge
(W (kg))
2
1
0
+ W
1 2
+ = kg
>25mm
<30mm
For RASC-(8/10)HNPE units
In case of RASC-(8/10)HNPE units, the following formula must
be used:
W = W
System example (W) =
C: Compensation value (kg) (Refer to the following table)
Model
RASC-8HNPE
RASC-10HNPE
!
C A U T I O N
Do not exceed the allowed maximum additional charge. Step 4: Total
refrigerant charge of the system (W
The total refrigerant charge of this system is calculated by the
following formula:
W
TOT
System example (W ) =
ToT
?
N O T E
• Charge the refrigerant correctly. Overcharge and insufficient charge
of the refrigerant may cause the compressor failure.
• Insulate the unions and flare-nuts at the piping connection part
completely.
• Insulate the liquid pipe for prevention of the capacity decrease
according to the ambient air conditions and the dewing on the pipe
surface by the low pressure.
• Check to ensure that there is no gas leakage. When large amount of
the refrigerant leaks, the troubles as follows may occur:
- Oxygen deficiency
- Harmful gas generation due to chemical reaction with fire.
• Use thick gloves to protect your hands from liquid refrigerant injuries
when handling refrigerant.
!
C A U T I O N
Check for refrigerant leakage thoroughly. In case that a large amount of
refrigerant is leaked, it may cause difficulty to breathe or the emission
of harmful gases if fire is lit up in the room. An excess or a shortage of
refrigerant is the main cause of trouble with the units.
Ceiling suspended
>25mm
<30mm
Drain pipe
+ W - C
1 2
+ – =
Compensation value (C (kg))
1.6
2.0
(kg))
TOT
= W + W
0
+ =
kg
kg