Toshiba RAV-SM2242DT-E - Manual (Page 24)

– 23 –
Concealed Duct High Static Pressure
Installation Manual
Tightening connection
CAUTION
Do not apply excessive torque. Otherwise, the nut
may crack depending on the conditions.
▼ 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 centres 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.
REQUIREMENT
Tightening with an excessive torque may crack the nut
depending on installation conditions.
Tighten the nut within the specified tightening torque.
„ Gas side refrigerant pipe
connection
• Turn up the pipe heat insulator to the unit side.
• Wrap the pipe with wet cloth.
• Remove the cup on the gas side piping by using a brazing
machine.
CAUTION
Do not burn the pipe heat insulator.
• Braze the attached joint part to the gas side piping and
braze the connection piping to the joint part.
• Turn back the pipe heat insulator and tie up with a banding
band.
Piping with outdoor unit
• For details of installation, refer to the Installation Manual of
the outdoor unit.
„ Evacuation
Using a vacuum pump, perform vacuuming from the charge
port of valve of the outdoor unit.
For details, follow to the Installation Manual attached to the
outdoor unit.
• Never use the refrigerant sealed in the outdoor unit for
evacuation.
REQUIREMENT
For the tools such as charge hose, etc., use those
manufactured exclusively for R410A.
(Unit: N•m)
Outer dia. of copper pipe Tightening torque
12.7 mm (dia.) 50 to 62 (5.0 to 6.2 kgf•m)
Externally
threaded side
Half union Flare nut
Internally
threaded side
Use a wrench to secure. Use a torque wrench to tighten.
Turn up pipe heat
insulator
Remove the all
brazed part.
Wet cloth
Remove the cap.
Connection pipe
Locally procured
Ø28.6 mm
Attached joint part
Braze all around
brazing
brazing
Tie up with a banding
band.
23-EN