Refrigerant Piping & Refrigerant Charge - Hitachi CENTRIFUGAL VRF RASC-HNPE Serie Manual De Instrucciones

REFRIGERANT PIPING & REFRIGERANT CHARGE
Model
Medium pressure setting
(f2: 0
RASC-6HP < 1.40 A
RASC-8HP < 3.10 A
RASC-10HP 2.65 ~ 3.10 A
7.5 DUCT CONNECTION
Install the duct with down slope to prevent entry of rain water.
Also, provide insulation for duct and connection in order to
prevent dew formation.
8 REFRIGERANT PIPING & REFRIGERANT CHARGE
8.1 PIPING WORK CONNECTION CONSIDERATIONS
8.1.1 Piping Materials
1 Prepare locally-supplied copper pipes.
2 Select the piping size with the correct thickness and correct
material which can have sufficient pressure strength.
3 Select clean copper pipes. Make sure there is no dust and
moisture inside. Blow the inside of the pipes with oxygen
free nitrogen to remove any dust and foreign materials
before connecting pipes.
4 After connecting the refrigerant piping, seal the open space
between Knockout hole and refrigerant pipes by using
insulation material.
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N O T E
• A system with no moisture or oil contamination will give maximum
performance and life cycle compared to that of a poorly prepared
system. Take particular care to ensure all copper piping is clean and
dry internally.
• There is no refrigerant in the cycle of the indoor unit.
!
C A U T I O N
• Cap the end of the pipe when pipe is to be inserted through a hole.
• Do not put pipes on the ground directly without a cap or vinyl tape at
the end of the pipe.
10 PMML0399B rev.0 - 11/2015
Fan motor current (A)
High pressure setting
1 ) (f2: 0
-
-
< 2.65
2 )
• 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 contents NH3 because can
damage cooper pipe material and can be a source of future leakage.
• Completely insulate both refrigerant gas piping and liquid piping
between the indoor units and the RASC unit.
• If not insulated, dew will occur on the piping surface.
1/50 or more