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y Use the tightening torque levels as listed in the
following table.
Outer dia. of connecting
pipe (mm)
Tightening torque (N·m)
6.4 14 to 18 (1.4 to 1.8 kgf·m)
9.5 34 to 42 (3.4 to 4.2 kgf·m)
12.7 49 to 61 (4.9 to 6.1 kgf·m)
15.9 63 to 77 (6.3 to 7.7 kgf·m)
y Tightening torque of are pipe connections.
Pressure of R410A is higher than that of R22.
(Approx. 1.6 times) Therefore, using a torque
wrench, tighten the are pipe connecting sections
which connect the indoor and outdoor units of the
specied tightening torque.
Incorrect connections may cause not only a gas
leak, but also a trouble of the refrigeration cycle.
CAUTION
Tightening with an excessive torque may crack the nut
depending on installation conditions.
◆ Piping with outdoor unit
Shape of valve differs according to the outdoor unit.
For details of installation, refer to the
Installation Manual of the outdoor unit.
Airtight test / Air purge, etc.
For airtight test, air purge, addition of refrigerant,
and gas leak check, refer to the Installation Manual
attached to the outdoor unit.
REQUIREMENT
Do not supply power to the indoor unit until the
airtight test and vacuuming are completed.
(If the indoor unit is powered on, the pulse motor
valve is fully closed, which extends the time for
vacuuming.)
◆ Open the valve fully
Open the valve of the outdoor unit fully.
For details, refer to the Installation Manual attached to
the outdoor unit.
◆ 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, be sure
to use the material with heat-resisting temperature
120°C or higher.
Using the attached heat insulation material, apply the
heat insulation to the pipe connecting section of the
indoor unit securely without gap.
REQUIREMENT
y 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.)
y Wrap heat insulator with its slits facing up
(ceiling side).
Wrap the pipe with the attached heat insulator
without any gap between the indoor unit.
Indoor unit
The seam must be faced upward
(ceiling side).
Flare nut
Heat insulator
of the pipe
Banding band
(locally
procured)
Union
Heat insulation
pipe
(Accessory)
7 Electrical connection
WARNING
y Use the specied wires for wiring connect the terminals. Securely x them to prevent external forces
applied to the terminals from affecting the terminals.
Incomplete connection or xation may cause a re or other trouble.
y Connect earth wire. (grounding work)
Incomplete grounding cause an electric shock.
Do not connect earth wires to gas pipes, water pipes, lightning conductor or telephone earth wires.
y 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 re.
CAUTION
y For communication line, use wires with the same type and size. lf each wire has a different type and
size from another one, it will cause a communication trouble.
y If incorrect / incomplete wiring is corried out, it will cause an electrical re or smoke.
y 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.
y Use the cord clamps attached to the product.
y Do not damage or scratch the conductive core and inner insulator of power and system interconnection wires
when peeling them.
y Use the power supply wire and control wires of specied thickness, type, and protective devices required.
y Do not connect 220V power to the terminal blocks (Uv (U1)), (Uv (U2)), (A), (B) for control wiring.
(Otherwise, the system will fail.)
y 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
y For power supply wiring, strictly conform to the Local Regulation in each country.
y For wiring of power supply of the outdoor units, follow the Installation Manual of each outdoor unit.
y After connecting wires to the terminal blocks, provide a trap and x wires with the cord clamp.
y Run the refrigerant piping line and control wiring line in the same line.
y Do not turn on the power of the indoor unit until vacuuming of the refrigerant pipes completes.
Power supply wire and communication wires specications
Power supply wire and communication wires are locally procured.
For the power supply specications, follow to the table below. If capacity is little, it is dangerous because overheat
or burnout may be caused.
For specications of the power capacity of the outdoor unit and the power supply wires, refer to the
Installation Manual attached to the outdoor unit.
Indoor unit power supply
y For the power supply of the indoor unit, prepare the exclusive power supply separated from that of the outdoor
unit.
y Arrange the power supply, circuit breaker, and main switch of the indoor unit connected to the same outdoor unit
so that they are commonly used.
y Power supply wire specication: Cable 3-core 2.5 mm², in conformity with Design 60245 IEC 57.
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