• Use the tightening torque levels as listed in the
following table.
Outer dia. of connecting
Tightening torque
pipe (in (mm))
(ft•lbs (N•m))
1/4" (6.4)
10 to 13 (14 to 18)
3/8" (9.5)
24 to 31 (33 to 42)
1/2" (12.7)
37 to 46 (50 to 62)
• 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 an error of the refrigeration cycle.
CAUTION
Tightening with an excessive torque may crack the nut
depending on installation conditions.
Airtight test / air purge, etc.
For air tightness test, adding refrigerant, refer to the
Installation Manual attached to the outdoor unit.
CAUTION
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.
23-EN
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 248 °F
(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).
• Apply heat insulating materials to both the gas side
and liquid side as shown:
To cover the pipe and the
indoor unit with a heat
insulator, do not make a
gap between them.
Indoor unit
Flare nut
Heat insulator
Union
of the pipe
Wrap the insulator
Banding band
with adhesive tale.
(Accessory)
(locally procured)
8
Electrical connection
WARNING
1. Use predefined wire and connect them certainly.
Keep the connecting terminal free from external
force.
Improper wire connection or clamping may result in
exothermic, fire or malfunction.
2. Connect ground wire. (grounding work)
Incomplete grounding cause an electric shock.
Do not connect ground wires to gas pipes, water
pipes, lightning rods or ground wires for telephone
wires.
3. Install appliance in accordance with national
wiring regulations.
Capacity shortage of circuit breaker or incomplete
installation may cause an electric shock or a fire.
CAUTION
• Consult local building codes, NEC (National Electrical
Code) or CEC (Canadian Electrical Code) for special
requirements.
• If incorrect / incomplete wiring is carried out, it will
cause an electrical fire or smoke.
• Install circuit breaker is not tripped by shock waves.
If circuit 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 cord and control wire of specified
thickness, type, and protective devices required.
• Do not connect 208 / 230 V power to the terminal
blocks (U1, U2, A, B etc.) 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.
• Do not turn on the circuit breaker of the indoor unit
until vacuuming of the refrigerant pipes completes.
REQUIREMENT
• For power supply wiring, strictly conform to the Local
Regulation in each country.
• Run the refrigerant piping line and control wiring line in
the same line.
– 12 –
Power supply wire and
control wires specifications
Power supply wire and control wires are locally
procured.
For the power supply specifications, follow to the table
below. If capacity is little, it is dangerous because
overheat or seizure may be caused.
Indoor unit power supply
For the power supply of the indoor unit, prepare the
exclusive power supply separated from that of the
outdoor unit.
▼ Power supply
Power supply
208 / 230-1-60
Control wiring, Central control wiring
• 2-core with non-polarity wires are used for the
control wiring between indoor unit and outdoor unit
and Central control wiring.
• To prevent noise trouble, use 2-core shielded wire.
• The length of the communication line means the total
length of the control wire length between indoor and
outdoor units added with the central control wire
length.
EN
24-EN