4
Piping connection
1.
Confirm that the valve is closed
2.
Connect the indoor unit and the outdoor unit with field-supplied
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.)
3. Tighten the flare nut with two spanners as shown in the right figure.
4. Apply the refrigerant oil (field-supplied) thinly at the seat surface of
the flare nut and pipe before connecting and tightening. And when
tightening the flare nut, use two spanners.
5.
Outdoor refrigerant piping should connect with stop valve.
Double spanner work
Tube size
Torque (Nm)
∅
6.35mm
20
∅
9.52mm
40
∅
12.7mm
60
∅
15.88mm
80
∅
19.05mm
100
Tightening torque for flare nut
6.
After finishing connecting the refrigerant pipes, keep it warm with the
insulation material as shown in the right figure.
For outdoor unit side, surely insulate every piping including valves.
Cover piping joints with pipe cover.
Using piping tape, apply taping starting from the entry of outdoor unit.
Fix the end of piping tape with adhesive tape.
When piping has to be arranged through above ceiling, closet or
area where temperature and humidity are high, use wind additional
commercially sold insulation for prevention of condensation
Clamp
(field-supplied)
Insulation
(field-supplied)
Refrigerant pipe
(field-supplied)
Insulation
(field-supplied)
Piping insulation procedure
5
Air tight test
Do use Nitrogen
Connect the gauge manifold using charging hoses with a nitrogen cylinder
to check joints of the liquid line and the gas line stop valves.
Perform the air tight test.
Don't open the gas line stop valves.
Apply nitrogen gas pressure of 4.15MPa.
Check any gas leakage at flare nut connections, or brazed parts by gas leak
detector or foaming agent.
Gas pressure doesn’t decrease, which is OK.
After the air tight test, release nitrogen gas.
Procedure
Completion
of
Refrigerant
piping
Applying
nitrogen
gas
Air tight procedure
Check of
pressure
decrease
Pass
Repairing
of leakage
part
INSTALLATION INSTRUCTIONS
HO2019292HA
14