Toshiba RAS-3M26U2AVG-E Service Manual page 56

Outer dia. of copper pipe
Ø6.35 mm
Ø9.52 mm
Ø12.70 mm
Outdoor unit
Fig. 10-2-8
Connectable capacity class
A B
05, 07, 10, 13
(with reducer)
16, 18, 22, 24
Tightening torque of flare pipe connections
The operating pressure of R32 is higher than that of
R22.
It is therefore necessary to firmly tighten the flare pipe
connecting sections (which connect the indoor and
outdoor units) up to the specified tightening torque.
Incorrect connections may cause not only a gas
leakage, but also damage to the refrigerant cycle.
Fig. 10-2-9
(Unit : N•m)
Tightening torque
16 to 18 (1.6 to 1.8 kgf•m)
30 to 42 (3.0 to 4.2 kgf•m)
50 to 62 (5.0 to 6.2 kgf•m)
Indoor unit
C Total
16
(with expander)
54
05, 07, 10, 13
Flare at
indoor unit side
Flare at
outdoor unit side
Pipe connection
1. Piping connections to the outdoor unit should be
arranged in the sequence A, B, C starting from
the bottom.
(For each piping connection, the gas pipe is on
the bottom and the liquid pipe is on the top.)
2. When multiple indoor units are to be connected to
the outdoor unit, make the ends of the pipes and
wires from each indoor unit to ensure that they will
be connected to the outdoor unit correctly.
(Problems caused by indoor units being con-
nected to the outdoor unit incorrectly are very
common in multiple-unit installations.)
3. The length and height difference of the connect-
ing pipes between the indoor and outdoor units
must be within the ranges indicated below.
• Total piping length :
Non. Additional refrigerant ....................... 40 m
Additional refrigerant .............................. 70 m
Additional 20 g of refrigerant ..... Per every 1 m
• Minimum piping length :
A or B or C = 3 m or more
• Maximum indoor piping length :
A or B or C = 25 m or less
• Maximum piping height difference :
A or B or C = 15 m or less
• Maximum piping/height difference between
2 units = 15 m or less
4. Connect 2 or more indoor units for heat pump.
5. If the outdoor units is to be mounted on a wall,
make sure that the platform supporting it is
sufficiently strong.
The platform should be designed and manufac-
tured to maintain its strength over a long period
of time, and sufficient consideration should be
given to ensuring that the outdoor unit will not fall.
6. When the outdoor unit is to be mounted high on
a wall, take particular care to ensure that parts
do not fall installer is protected.
7. When doing installation work on level ground, it
is usual to wiring and piping connections to the
indoor units. And/then make to the outdoor unit.
However if outdoor work is difficult it is possible
instead to make changes to the procedure.
For example by making adjustments to the wiring
and piping length on the inside
(rather than the outside).
- 56 -
FILE NO. SVM-18051
..................... 41 to 70 m
A C
Outdoor
unit
B
Fig. 10-2-10