Refrigerant piping & refrigerant charge
13 REFRIGERANT PIPING & REFRIGERANT CHARGE
13.1 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 con-
necting pipes.
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 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
13.2 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
23
_PMML0251A_r2.indb 23
Fire-Proof
Section Treatment
PMML0251A rev.2 - 02/2013
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 long-
er 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 because it can
damage cooper pipe material and can be a source of future leak-
age.
Completely insulate both refrigerant gas piping and liquid piping
between the indoor unit(s) and the outdoor unit.
If not insulated, dew will ocur 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 Suspending
For piping along
Heavies
the wall
For instant
installation work
06/02/2013 9:05:00