REFRIGERANT PIPING & REFRIGERANT CHARGE
8 REFRIGERANT PIPING & REFRIGERANT CHARGE
8.1 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.
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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 all copper piping is clean and
dry internally.
•
There is no refrigerant in the cycle of the indoor unit.
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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.
8.2 PIPING CONNECTION FOR OUTDOOR UNIT
1 Take the piping cover away from the unit. Then fetch the
pipes through the rear side and route piping according to
the installation place as shown in the figure. Make holes
by cutting along the guideline at the rear of the cover or
punching with a driver. Remove the burr with a cutter, and
place a insulation (field supplied) to protect cables and
pipes.
Pipe cover
Rear side
piping
Direction to remove pipe cover
8.2.1 Outdoor unit stop valve
Operation of stop valve should be performed according to the figures and tables below:
8
PMML0398B rev.0 - 11/2015 - P5416651
Stop
Connecting
valve
piping
•
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 because it can
damage cooper pipe material and can be a source of future leakage.
After connecting the refrigerant piping, seal the refrigerant
pipes by using the field-supplied insulation material. Insulate
the unions and flare-nuts at the piping connections completely.
Insulate the liquid piping and gas piping completely to avoid
decreasing of performance and dewing on the surface of the
pipe.
!
C A U T I O N
•
Do not use insulation material that contains NH3 because it 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 unit(s) and the outdoor unit.
•
If not insulated, dew will ocur on the piping surface.
2 Attach the pipe cover in order to prevent rainwater from
entering inside the cabinet.
3 Use a pipe bender for pipe bending work when connecting
pipes.
4 Check to ensure that the stop valves are completely closed
before connecting pipes.
5 Connect the field supplied refrigerant pipes to the indoor unit
and outdoor unit. Apply the oil thinly at the seat flare nut and
pipe before tightening.
6 Operation of stop valve should be performed according to
the figure below.