Electrical Work - Toshiba Super MMU-AP0092H Service Manual

6
REFRIGERANT PIPING AND EVACUATING
Tightening connection
CAUTION
• Do not apply excessive torque. Otherwise, the nut
may crack depending on the conditions.
(Unit : N•m)
Outer dia. of copper pipe Tightening torque
6.4 mm (dia.) 14 to 18 (1.4 to 1.8 kgf•m)
9.5 mm (dia.) 33 to 42 (3.3 to 4.2 kgf•m)
12.7 mm (dia.) 50 to 62 (5.0 to 6.2 kgf•m)
15.9 mm (dia.) 68 to 82 (6.8 to 8.2 kgf•m)
u 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.
Align the centers of the connecting pipes and tighten
the flare nut as far as possible with your fingers.
Then tighten the nut with a spanner and torque
wrench as shown in the figure.
Work using double spanner
REQUIREMENT
Tightening with an excessive torque may crack the
nut depending on installation conditions.
Tighten the nut within the specified tightening torque.
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.
n 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.
Thermal insulation process
Apply thermal insulation for the pipes separately at
liquid side and gas side.
For the thermal insulation to the pipes at gas side,
be sure to use the material with heat-resisting
temperature 120°C or higher.
Using the attached thermal insulation material,
apply the thermal insulation to the pipe connecting
section of the indoor unit securely without gap.
REQUIREMENT
• Apply the thermal insulation to the pipe connect-
ing 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).
Indoor unit
Union
Heat insulation pipe Heat insulator
(Accessory) of the pipe
Flare nut
7

ELECTRICAL WORK

WARNING
1. Using the specified wires, ensure to connect
the wires, and fix wires securely so that the
external tension to the wires do not affect the
connecting part of the terminals.
Incomplete connection or fixation may cause a fire,
etc.
2. Be sure to connect earth 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. 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
• If incorrect/incomplete wiring is carried out, it will
cause an electrical fire or smoke.
• Be sure to 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.
• Be sure to use the cord clamps attached to the
product.
• Do not damage or scratch the conductive core and
inner insulator of power and inter-connecting wires
when peeling them.
• Use the power cord and Inter-connecting wire of
specified thickness, type, and protective devices
required.
• Never connect 220–240V power to the terminal
blocks ( , , A , B , etc.) for control wiring.
U U
1 2
(Otherwise, the system will fail.)
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.
• 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.
• After connecting wires to the terminal blocks,
provide a trap and fix wires with the cord clamp.
• Run the refrigerant piping line and control wiring line
in the same line.
• Do not turn on the power of the indoor unit until
vacuuming of the refrigerant pipes completes.
n Power supply wire and communication
wires specifications
Power supply wire and communication wires are
procured locally.
For the power supply specifications, follow to the
table below.
If capacity is little, it is dangerous because over-
heat or seizure may be caused.
For specifications 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
• For the power supply of the indoor unit, prepare the
exclusive power supply separated from that of the
outdoor unit.
• Arrange the power supply, earth leakage breaker,
and main switch of the indoor unit connected to the
same outdoor unit so that they are commonly used.
• Power supply wire specification : Cable 3-core
2.5mm², in conformity with Design 60245 IEC 57.
u Power supply
220–240V ~, 50Hz
Power supply
220–220V ~, 60Hz
Power supply switch/Earth leakage breaker or power supply
wiring/fuse rating for indoor units should be selected by the
accummulated total current values of the indoor units.
Power supply wiring Below 50m 2.5 mm²
Control wiring, Central controller wiring
• 2-core with polarity wires are used for the Control
wiring between indoor unit and outdoor unit and
Central controller wiring.
• To prevent noise trouble, use 2-core shield wire.
• The length of the communication line means the
total length of the inter-unit wire length between
indoor and outdoor units added with the central
control system wire length.