Refrigerant Piping And Charge - Hitachi EXV-2.0E2 Manuel D'installation Et De Fonctionnement

REFRIGERANT PIPING AND CHARGE

7 REFRIGERANT PIPING AND CHARGE
7.1 GENERAL NOTES BEFORE PERFORMING PIPE WORK
1 Prepare locally-supplied copper pipes.
2 Select the piping size with the correct thickness and correct
material able to withstand sufficient pressure.
3 Select clean copper pipes. Make sure that there is no dust
or moisture inside the pipes. Blow the inside of the pipes
with oxygen free nitrogen to remove any dust and foreign
materials before connecting them.
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N O T E
A system with no moisture or oil contamination will give maximum
performance and lifecycle compared to that of a poorly prepared system.
Take particular care to ensure that all copper piping is clean and dry
internally.
!
D A N G E R
The system design pressure is 4.15 MPa. The compression strength of
the pipes must exceed 12.45 MPa (3 times the design pressure).
!
C A U T I O N
Cap the end of the pipe when pipe is to be inserted through a wall hole.
Do not put pipes on the ground directly without a cap or vinyl tape at the
end of the pipe.
7.2 REFRIGERANT PIPE CONNECTIONS
The DX-Interface unit is set up to be connected by Flare Nut (factory supplied). Perform the indicated pipe work by maintaining the
dimensions indicated in the following tables.
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Size of pipes
units: mm (inch)
Nominal
Units
diameters
EXV-2.0E2 (1/4)
EXV-(2.5-10.0)E2 (3/8)
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N O T E
• Flare nuts tightening torque
• Always use two wrenches or fix spanners when tightening the flare
nuts on the refrigerant pipes.
• If any failure occurs during this process the result could be pipe
damage or refrigerant leak.
9 PMML0293A rev.2 - 08/2016
If piping installation is not completed until next day or over
a longer period of time, braze off the ends of the piping and
charge with oxygen free nitrogen through a Schrader valve type
access fitting to prevent moisture and particle contamination.
Do not use insulation material that contains NH3, as it can
damage copper pipe material and become a source of future
leakage.
Completely insulate both refrigerant gas piping and liquid piping
between the indoor unit and the outdoor unit.
If not insulated, in cooling mode and high ambient humidity
conditions, dew will appear on the piping surface.
Refrigerant circuit and Water circuit must be performed and
inspected by a licensed technician and must comply with all
relevant European and national regulations.
Flare pipe
Outer
dimensions
diameters
A
Ø +0/-0.4
6.35 9.1
9.53 13.2
After connecting the refrigerant piping seal the open space
between the knockout hole and refrigerant pipes by using
insulation material as shown below:
A. Insulation.
B. Field-supplied
refrigeration piping.
Minimum thickness Flare nut
R410A dimensions B
0.5 17
0.6 22
Tightening Torque
(Nm)
20
40
A