Installing The Coupler Heat Insulation - Hitachi R410A Manuel D'installation

6.2.4. Bending pipes
• If pipes are shaped by hand, be careful not to collapse
them.
• Do not bend the pipes in an angle more than 90°.
• When pipes are repeatedly bend or stretched, the material will
harden, making it dif¿ cult to bend or stretch them anymore.
• Do not bend or stretch the pipes more than 3 times.
To prevent breaking of the pipe, avoid sharp bends.
If the pipe is bent repeatedly at the same place, it will
break.
Pipe connection
Be sure to connect the pipe against the port on the
indoor unit correctly. If the centering is improper, the
À are nut cannot tighten smoothly. If the À are nut is
forced to turn, the threads will be damaged.
Do not remove the À are nut from the indoor unit pipe
until immediately before connecting the connection
pipe.
Hold the torque wrench at its grip, keeping it at a right
angle with the pipe, in order to tighten the À are nut
correctly.
Tighten the À are nuts with a torque wrench using
the speci¿ ed tightening method. Otherwise, the À are
nuts could break after a prolonged period, causing
refrigerant to leak and generate a hazardous gas if the
refrigerant comes into contact with a À ame
Connect the piping so that the control box cover can
easily be removed for servicing when necessary.
In order to prevent water from leaking into the control
box, make sure that the piping is well insulated.
When the À are nut is tightened properly by your hand, hold
the body side coupling with a wrench, then tighten with a
torque wrench. (See the table below for the À are nut tighten-
ing torques.)
Torque wrench
Indoor unit pipe
(Body side)
Flare nut [mm (in.)]
6.35 (1/4) dia.
9.52 (3/8) dia.
12.70 (1/2) dia.
15.88 (5/8) dia.
19.05 (3/4) dia.
En-10
9374318438-05_IM_EN.indd 10
CAUTION
CAUTION
Tighten with 2 wrenches.
Holding wrench
Flare nut
Connection pipe
Tightening torque [N·m (lbf·ft)]
16 to 18 (11.8 to 13.3)
32 to 42 (23.6 to 31.0)
49 to 61 (36.1 to 45.0)
63 to 75 (46.5 to 55.3)
90 to 110 (66.4 to 81.1)
6.2.5. Connection pipes
Indoor unit
(1) Remove the caps and plugs from the pipes.
(2) Centering the pipe against port on the indoor unit, turn the
À are nut with your hand.
Connection pipe
(Liquid)
Indoor unit

6.3. Installing the coupler heat insulation

After checking for gas leaks, insulate by wrapping insulation
around the 2 parts (gas and liquid) of the indoor unit coupling,
using the coupler heat insulation.
After installing the coupler heat insulation, wrap both ends
with vinyl tape so that there is no gap.
Coupler heat insulation
Body
Be sure to overlap the
insulation
CAUTION
Must ¿ t tightly against body without any gap.
Connection pipe
(Gas)
No gap
Coupler heat
insulation
9/17/2010 1:47:58 PM