Toshiba MMD-AP0724H-E Manuel D'installation page 45

Work using double spanner
• Use the tightening torque levels as listed in the table
below.
Outer dia. of connecting
Tightening torque (N•m)
pipe (mm)
12.7 50 to 62 (5.0 to 6.2 kgf•m)
• 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
Tightening with an excessive torque may crack the nut
depending on installation conditions.
Gas side refrigerant pipe
connection
• Turn up the pipe heat insulator to the unit side.
• Wrap the pipe with wet cloth.
Turn up pipe heat
insulator
Wet cloth
Remove the all
brazed part.
• Remove the cup on the gas side piping by using a
brazing machine.
87-EN
CAUTION
Do not burn the pipe heat insulator.
Remove the cap.
Connection pipe
Locally procured
Ø22.2 mm
• Braze the connection piping to the joint part.
Braze all around
• Turn back the pipe heat insulator and tie up with a
banding band.
Tie up with a banding band.
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.
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).
Indoor unit
Flare nut
Union
Heat insulator of
the pipe
Heat insulation pipe Banding band
(Accessory) (locally procured)
– 44 –
88-EN