Refrigerant Piping & Refrigerant Charge; Piping Materials; Suspension Of Refrigerant Piping - Hitachi RPI-10FSNE Installation And Operation Manual

REFRIGERANT PIPING &
REFRIGERANT CHARGE
11. REFRIGERANT PIPING & REFRIGERANT CHARGE

11.1. 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 as shown bellow:
Unit side
Insulation material

NOTE:
- 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.

11.2. SUSPENSION OF REFRIGERANT PIPING

Suspend the refrigerant piping at certain points and prevent
the refrigerant piping from touching the weak part of the
building such as wall, ceiling, etc...
(If touched, abnormal sound may occur due to the vibration
of the piping. Pay special attention in case of short piping
length).
1~15m
Indoor unit
Insulation material
Field Supplied
refrigerant pipe
Insulation material
Fire-Proof sectrion
Treatment

CAUTION:
- 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.
- 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 outdoor unit.
- If not insulated, dew will occur on the piping surface.
Do not fix the refrigerant piping directly with the metal fittings
(The refrigerant piping may expand and contract).
Some examples for suspension method are shown below.
For Piping along
For suspension
the wall
Heavies
PMGB0126A rev.2 - 11/2006
For Instant
Installation work
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