Refrigerant Piping And Evacuating - Toshiba RAV-SM561CT-E Service Manual

4

REFRIGERANT PIPING AND EVACUATING

Refrigerant Piping
• The connecting sections of the refrigerant pipes are
provided at the positions in the figure below.
Rear side
Upper side
Right
1. Use copper pipe with 0.8 mm or more thickness.
(In case pipe size is Ø15.9, with 1.0mm or more.)
2. Flare nut and flare works are also different from
those of the conventional refrigerant.
Take out the flare nut attached to the main unit of
the air conditioner, and use it.
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)
Permissible Piping Length and Heat
They vary according to the outdoor unit. For details,
refer to the Installation Manual attached to the outdoor
unit.
Flaring
Insert a flare nut into the pipe, and flare the pipe.
As the flaring sizes of R410A differ from those of
refrigerant R22, the flare 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 flaring : B (Unit : mm)
Rigid (Clutch type)
R410A tool used
Outer diam. of
copper pipe
R410A
6.4 to 15.9 0 to 0.5 (Same as left)
Imperial (Wing nut type)
Outer diam. of copper pipe
6.4 or 9.5
12.7 or 15.9
* When using the drain up kit sold
separately, the pipe can be drawn
out only from the upper side.
Conventional tool used
R22 R410A R22
1.0 to 1.5 0.5 to 1.0
R410A R22
1.5 to 2.0 1.0 to 1.5
2.0 to 2.5 1.5 to 2.0
• Flaring diam. meter size : A (Unit : mm)
Outer diam. of copper pipe
6.4
9.5
12.7
15.9
In case of flaring for R410A with the conventional
*
flare tool, pull it out approx.
0.5 mm more than that for R22 to
adjust to the specified flare size.
The copper pipe gauge is useful
for adjusting projection margin size.
Tightening connection
• Do not apply excessive torque. Otherwise, the
nut may crack depending on the conditions.
Outer diam. of copper pipe
6.4 mm (diam.)
9.5 mm (diam.)
12.7 mm (diam.)
15.9 mm (diam.)
• 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.
B 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 as far as possible with your fingers. Then
tighten the nut with a spanner and torque wrench as
shown in the figure.
Half union
Externally
threaded side
Use a wrench to secure.
28
+0
A
- 0.4
R410A
9.1
13.2
16.6
19.7
CAUTION
(Unit : N•m)
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)
68 to 82 (6.8 to 8.2 kgf•m)
Flare nut
Internally
threaded side
Use a torque wrench to tighten.
R22
9.0
13.0
16.2
19.2
A
Flare at
indoor
unit side
Flare at
outdoor
unit side