Toshiba RAV-HM1101FT-E, Installation Manual, Page: 16 / 31

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Refrigerant piping
CAUTION
• Use flare nuts that are included with the unit. Using
different flare nuts may cause refrigerant gas
leakage.
• After refrigerant piping has been connected, do not
turn on the power until gas leakage check is finished.
If refrigerant gas leaks, refrigerant leak detection
sensor operates and a fan automatically rotates,
causing air conditioner not to operate.
 Refrigerant piping
Use the following item for the refrigerant piping.
Material: Seamless phosphorous deoxidized
copper pipe.
Ø6.35, Ø9.52, Ø12.7 Wall thickness 0.8 mm or more
Ø15.88 Wall thickness 1.0 mm or more
REQUIREMENT
When the refrigerant pipe is long, provide support
brackets at intervals of 2.5 - 3 m to clamp the refrigerant
pipe. Otherwise, abnormal sound may be generated.
CAUTION
IMPORTANT 4 POINTS FOR PIPING WORK
1. Reusable mechanical connectors and flared joints are
not allowed indoors. When mechanical connectors
are reused indoors, sealing parts shall be renewed.
When flared joints are reused indoors, the flare part
shall be refabricated.
2. Tight connection (between pipes and unit)
3. Evacuate the air in the connecting pipes by using
VACUUM PUMP.
4. Check the gas leakage. (Connected points)

Pipe size
 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 flare nut into the pipe, and flare the pipe.
As the flaring sizes of R32 differ from those of
refrigerant R22, the flare tools newly manufactured
for R32 are recommended.
However, the conventional
tools can be used by adjusting
projection margin of the
copper pipe.
▼ Projection margin in
flaring: B (Unit: mm)
Rigid (Clutch type)
▼ Flaring dia. meter size: A (Unit: mm)
CAUTION
• Do not scratch the inner surface of the flared part
when removing burrs.
• Flare processing under the condition of scratches on
the inner surface of flare processing part will cause
refrigerant gas leak.
• Check that the flared part is not scratched, deformed,
stepped, or flattened, and that there are no chips
adhered or other problems, after flare processing.
• Do not apply refrigerating machine oil to the flare
surface.
Model
name
RAV- HM56 type
HM80,
HM90 to HM160
type
Pipe size
Gas side 12.7 mm 15.9 mm
Liquid side 6.4 mm 9.5 mm
Outer dia. of
copper pipe
R32 tool used
Conventional
tool used
6.4, 9.5
0 - 0.5 1.0 - 1.5
12.7, 15.9
Outer dia. of
copper pipe
A
+0
–0.4
6.4 9.1
9.5 13.2
12.7 16.6
15.9 19.7
B
A
 Tightening connection
CAUTION
Do not apply excessive torque. Otherwise, the nut may
crack depending on the conditions.
▼ Tightening torque of flare pipe connections
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 with your fingers. Then tighten the nut with
a spanner and torque wrench as shown in the figure.
REQUIREMENT
Tighten the nut within the specified tightening torque.
 Evacuation
Perform vacuuming from the charge port of valve of the
outdoor unit by using a vacuum pump.
For details, follow to the Installation Manual attached to
the outdoor unit.
• Do not use the refrigerant sealed in the outdoor unit
for evacuation.
REQUIREMENT
For the tools such as charge hose, use those
manufactured exclusively for R32.
 Refrigerant amount to be
added
For addition of the refrigerant, add refrigerant “R32”
referring to the attached Installation Manual of outdoor
unit.
Use a scale to charge the refrigerant of specified
amount.
REQUIREMENT
• Charging an excessive or too little amount of
refrigerant causes a trouble of the compressor.
Charge the refrigerant of specified amount.
• A personnel who charged the refrigerant should write
down the pipe length and the added refrigerant
amount in the F-GAS label of the outdoor unit. It is
necessary to fix the compressor and refrigeration
cycle malfunction.

Open the valve fully
CAUTION
A brazed, welded, or mechanical connection shall be
made before opening the valves to permit refrigerant to
flow between the refrigerating system parts.
Open the valve of the outdoor unit fully. A 4 mm-
hexagonal wrench is required for opening the valve.
For details, refer to the Installation Manual attached to
the outdoor unit.
Unit: N•m
Outer dia. of copper pipe Tightening torque
6.4 mm 14 - 18
9.5 mm 34 - 42
12.7 mm 49 - 61
15.9 mm 68 - 82
Work using two spanners
29-EN 30-EN