– 19 –
• Use the tightening torque levels as listed in the table
below.
• Tightening torque of flare pipe connections.
Pressure of R410A is higher than that of R22.
(Approx. 1.6 times) Therefore, using a torque wrench,
tighten the flare pipe connecting sections which
connect the indoor and outdoor units of the specified
tightening torque.
Incorrect connections may cause not only a gas leak,
but also a trouble of the refrigeration cycle.
CAUTION
CAUTION
Tightening with an excessive torque may crack the nut
depending on installation conditions.
Airtight test / Air purge, etc.
For air tightness test, vacuum drying and adding
refrigerant, refer to the Installation Manual attached
tothe outdoor unit.
Open the valve fully
Open the valve of the outdoor unit fully.
Heat insulation process
Apply heat insulation for the pipes separately at liquid
side and gas side.
• For the heat insulation to the pipes at gas side, use
the material with heat-resisting temperature 120 °C or
higher.
• To use the attached heat insulation pipe, apply the
heat insulation to the pipe connecting section of the
indoor unit securely without gap.
REQUIREMENT
• Apply the heat insulation to the pipe connecting
section of the indoor unit securely up to the root
without exposure of the pipe. (The pipe exposed to
the outside causes water leak.)
• Wrap heat insulator with its slits facing up (ceiling
side).
Outer dia. of connecting
pipe (mm)
Tightening torque (N•m)
6.4
14 to 18
9.5
34 to 42
12.7
49 to 61
15.9
68 to 82
Wrap the pipe with the attached heat insulator
without any gap between the indoor unit.
The seam must be faced
upward (ceiling side).
Indoor unit
Flare nut
Union
Heat insulation
pipe
(Accessory)
Banding band
(Locally
procured)
Heat insulator
of the pipe
8
Electrical connection
WARNING
• Use the specified wires for wiring connection to the terminals. Securely fix them to prevent external forces
applied to the terminals from affecting the terminals.
Incomplete connection or fixation may cause a fire or other trouble.
• Connect earth wire. (grounding work)
Incomplete earthing cause an electric shock.
Do not connect earth wires to gas pipes, water pipes, lightning conductor or telephone earth wires.
• Appliance shall be installed in accordance with national wiring regulations.
Capacity shortage of power circuit or incomplete installation may cause an electric shock or a fire.
CAUTION
CAUTION
• The wire size and wire length of the communication line differs depending on the outdoor unit series to be
connected.
• If incorrect / incomplete wiring is carried out, it will cause an electrical fire or smoke.
• Install an earth leakage breaker that is not tripped by shock waves.
If an earth leakage breaker is not installed, an electric shock may be caused.
• Use the cord clamps attached to the product.
• Do not damage or scratch the conductive core and inner insulator of power and control wires when peeling them.
• Use the power supply wire and control wires of specified thickness, type, and protective devices required.
• Do not connect 208-240 V power to the terminal blocks (Uv (U1)), (Uv (U2)), (A), (B) for control wiring. (Otherwise,
the system will fail.)
• Perform the electric wiring so that it does not come to contact with the high-temperature part of the pipe.
The coating may melt resulting in an accident.
REQUIREMENT
• For power supply wiring, strictly conform to the Local Regulation in each country.
• For wiring of power supply of the outdoor units, follow the Installation Manual of each outdoor unit.
• After connecting wires to the terminal blocks, provide a trap and fix wires with the cord clamp.
• Run the refrigerant piping line and communication line in the same line.
• Do not turn on the power of the indoor unit until vacuuming of the refrigerant pipes completes.
37-EN
38-EN
