Toshiba SUPER MMK-AP0073H (IN) Service Manual page 32

9
REFRIGERANT PIPING
Tightening connection
CAUTION
• Do not apply excessive torque. Otherwise, the nut
may crack depending on the conditions.
(Unit : N•m)
Outer diam.
Tightening torque
of copper pipe
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.
Heat insulation
Heat insulation for the pipes should be done sepa-
rately for the liquid side and gas side.
Because both of the liquid and gas side pipes
become a low temperature during cooling
operation, sufficient heat insulation should be done
to prevent condensation.
• Heat insulator with a heat resistance of 120°C or
more must be used for the gas side pipe.
• The pipe connection section of the indoor unit
must be heat insulated securely and compactly
with the attached heat insulator.
Fix with vinyl tape
Heat insulator Local side pipe
(attached)
n Airtight test/Air purge, etc.
For airtight test, air purge, addition of refrigerant,
and gas leak check, follow the Installation Manual
attached to the outdoor unit.
n Open fully valves of the outdoor
unit
n Gas leak check
Check with a leak detector or soap water whether
gas leaks or not, from the pipe connecting
section or cap of the valve.
REQUIREMENT
Use a leak detector manufactured exclusively HFC
refrigerant (R410A, R134a, etc.).
10
ELECTRIC WORK
1. Using the specified wires, ensure to connect the wires, and fix wires securely so that the exter-
nal 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.
• 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 (
(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.
WARNING
CAUTION
, , , , etc.) for control wiring.
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