Daikin LCBKQ3AV1, Installation Manual, Page: 8 / 14

6 English
5-2 Protection against Contamination when
Installing Pipes
Protect the piping to prevent moisture, dirt, dust, etc. from entering
the piping.
Note
Exercise special caution to prevent dirt or dust when passing piping
through holes in walls and when passing pipe edges to the exterior.
5-3 Pipe Connection
• Be sure to perform nitrogen permutation or nitrogen blow when brazing.
Brazing without performing nitrogen permutation or nitrogen blow
into the piping will create large quantities of oxidized film on the
inside of the pipes, adversely affecting valves and compressors in
the refrigerating system and preventing normal operation.
• The pressure regulator for the nitrogen released when doing the
brazing should be set to 0.02 MPa (about 0.2kg/cm
2
:Enough to
feel a slight breeze on your cheek).
Note
Do not use anti-oxidants when brazing the pipe joints.
Residue can clog pipes and break equipment.
5-4 Connecting the Refrigerant Piping
CAUTION
• Do not connect an onsite piping to an incorrect one. Wrong con-
nection will cause a malfunction.
Remove the piping slot cap before connecting the pipe.
• Do not let the onsite piping contact other piping, the bottom frame
and the side panel of the product.
Precautions for piping
• Always connect the piping within the range of the max. permissi-
ble piping length and the permissible difference in height.
• Bend the pipe allowing for a possibly large diameter. Do not bend
the pipe repeatedly.
• Install a gauge joint to install the pressure sensor on the inlet and
outlet pipes of the booster unit when connecting the AIRNET sys-
tem (Refer to the Service Manual for details).
• Create a trap on the gas pipe at 5 m intervals if the outdoor unit is
located above the booster unit (to ensure the smooth return of oil
in the riser pipe (Refer to Figure
1
below)).
• Create a trap on the gas pipe at 5 m intervals if the booster unit is
located below the outdoor unit (to ensure the smooth return of oil
in the riser pipe (Refer to Figure
2
below)).
Operation Method of Shutoff Valves
Follow the instructions below when operating each shutoff valve.
CAUTION
• Do not open the shutoff valve until the steps specified in
“ 6-4 Checking of Device and Installation Conditions ” is com-
pleted.
Do not leave the shutoff valve opened without turning the power
on, otherwise refrigerant may be condensed in the compressor
and the insulation of the main power supply circuit may be
degraded.
• Be sure to use an exclusive tool to handle the shutoff valve. The
shutoff valve is not of back sheet type. Excessive force imposed
may break the valve.
• Use a charge hose when using the service port.
• Make sure that there is no refrigerant gas leakage after the valve
cover and cap are securely tightened.
〈
Tightening torque
〉
Check with the following table the sizes of shutoff valves incorporated
by each model and the tightening torque values of the respective
shutoff valves.
Shutoff valve sizes
〈
Opening method
〉
1. Remove the valve cover and turn the shaft anticlockwise with a
hexagon wrench.
2. Turn the shaft until the shaft stops.
3. Tighten the valve cover securely. Refer to the above table for the
tightening torque according to the size.
Place Installation period Protection method
Outdoor
More than a month Pinch the pipe
Less than a month
Pinch or tape the pipe
Indoor Regardless of the period
Refrigerant pipe
Regulator
Handy valve
Taping
Nitrogen
Nitrogen
Location to
be brazed
A
Liquid piping inlet
Connect the pipe to the liquid pipe
(refrigeration) of the outdoor unit.
B
Liquid piping outlet
Connect the pipe to the liquid pipe
of the refrigeration showcase.
C
Suction pipe
Connect the pipe to the gas pipe of
the refrigeration showcase.
D
Discharge pipe
Connect the pipe to the gas pipe
(refrigeration ) of the outdoor unit.
Liquid side shutoff valve
φ
9.5
Gas side shutoff valve
φ
9.5
Shutoff
valve sizes
Tightening torque N•m (closes clockwise)
Shaft (valve body) Valve cover Service port
φ
9.5 5.4~6.5
Hexagon
wrench: 4mm
13.5~16.5 11.5~13.9
A
B
Liquid piping outlet
C
Suction
piping
D
Discharge piping
Refrigeration
showcase
Refer to the
pipe diameter of
the showcase
Booster
unit
Liquid
piping
outlet
Set the
piping such
that it slants
downward.
Main gas piping of
outdoor unit
(refrigeration)
Connect from the upper
part of the main pipe
To prevent the unit from oil
and liquid refrigerant flowing
in from the main pipe while
the booster unit is stopped
Piping length shall be 30 m or less.
1 2
When the refrigeration
showcase is below the
booster unit When the outdoor
unit is above the
booster unit
Create a trap Create a trap
Refrigeration showcase
Booster unit
Booster
unit
Outdoor
unit
About
5m
About
5m
Service port
Valve cover
Hexagon hole
Shaft
Sealing part