Refrigerant Piping - Toshiba MML-AP0074NH-E Installationshandbuch

7

REFRIGERANT PIPING

Refrigerant piping
1. Use copper pipe with 0.8 mm or more thickness.
2. Flare nut and fl are works are also different from those
of the conventional refrigerant.
Take out the fl are nut attached to the main unit of the
air conditioner, and use it.
REQUIREMENT
When the refrigerant pipe is long, provide support
brackets at intervals of 2.5 to 3 m to clamp the refrigerant
pipe. Otherwise, abnormal sound may be generated.
CAUTION
IMPORTANT 4 POINTS FOR PIPING WORK
1. Remove dust and moisture from the inside of
the connecting pipes.
2. Tight connection (between pipes and unit)
3. Evacuate the air in the connecting pipes using
VACUUM PUMP.
4. Check the gas leakage. (Connected points).
Pipe size
AP007 to
MML-
AP012 type
Gas side 9.5
Liquid side 6.4
Permissible piping length and
height difference
They vary according to the outdoor unit.
For details, refer to the Installation Manual attached
to the outdoor unit.
Flaring
• Cut the pipe with a pipe cutter.
Remove burrs completely.
Remaining burrs may cause gas leakage.
• Insert a fl are nut into the pipe, and fl are the pipe.
As the fl aring sizes of R410A differ from those of
refrigerant R22, the fl are tools newly manufactured for
R410A are recommended.
However, the
conventional tools can
be used by adjusting
projection margin of the
copper pipe.
Projection margin in fl aring: B (Unit: mm)
Rigid (Clutch type)
Outer dia. of
copper pipe
6.4 , 9.5
12.7
Flaring dia. meter size: A (Unit: mm)
Outer dia. of copper pipe
12.7
* In case of fl aring for R410A with the
conventional fl are tool, pull it out
approx. 0.5 mm more than that for R22
to adjust to the specifi ed fl are size.
The copper pipe gauge is useful for
adjusting projection margin size.
Tightening connection
(dia : mm)
AP015 to
AP018 type
• Do not apply excessive torque. Otherwise, the
12.7
nut may crack depending on the conditions.
6.4
Outer dia. of copper pipe
6.4 mm (dia.)
9.5 mm (dia.)
12.7 mm (dia.)
Tightening torque of fl are pipe connections
Pressure of R410A is higher than that of R22.
(Approx. 1.6 times) Therefore, using a torque wrench,
tighten the fl are pipe connecting sections which connect
the indoor and outdoor units of the specifi ed 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 fl are nut as far as possible
with your fi ngers. Then tighten
the nut with a spanner and
torque wrench as shown in the
fi gure.
–13–
Installation Manual
Conventional
R410A tool used
tool used
R410A
0 to 0.5 1.0 to 1.5
A +0
-0.4
R410A
6.4 9.1
9.5 13.2
16.6
CAUTION
Tightening torque
14 to 18 (1.4 to 1.8 kgf·m)
33 to 42 (3.3 to 4.2 kgf·m)
50 to 62 (5.0 to 6.2 kgf·m)
Work using double spanner
Toshiba 1112750201 (EN)
R410A
EN
FR
DE
IT
ES
PT
NL
GR
RU
TR
CS
LV
(Unit: N·m)
SK
SI
13-EN