Refrigerant Piping - Toshiba RAV-SM304ATP-E Installation Manual

5

Refrigerant piping

Optional installation parts
■
(Locally procured)
Parts name
Refrigerant piping
A Liquid side: Ø6.4 mm One each
Gas side: Ø9.5, 12.7 mm
Pipe insulating material
B
(polyethylene foam, 6 mm thick)
C Putty, PVC tape One each
Refrigerant piping connection
■
CAUTION
Take note of these 4 important points below for
piping work.
1. Keep dust and moisture away from inside the
connecting pipes.
2. Tightly connect the connection between pipes and
the unit.
3. Evacuate the air in the connecting pipes using a
VACUUM PUMP.
4. Check for gas leaks at connection points.
Piping connection
Liquid side Gas side
RAV-
Outer Outer
Thickness
diameter diameter
SM30 Ø6.4 0.8 Ø9.5
SM40 Ø6.4 0.8 Ø12.7
17-EN
Flaring
1
Cut the pipe with a pipe cutter.
Be sure to remove burrs that may cause a gas
leak.
Q'ty
2
Insert a flare nut into the pipe, and then flare
the pipe.
Use the flare nuts supplied with the air conditioner
or those for R410A.
1
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 the projection margin of the copper pipe.
Projection margin in flaring: B (Unit: mm)
Rigid (Clutch type)
R410A tool used
Outer dia. of
copper pipe
R410A
6.4
(Unit: mm)
9.5 0 to 0.5
12.7
Thickness
Flaring dia. size: A (Unit: mm)
0.8
A
0.8
Outer dia. of copper pipe
6.4
9.5
12.7
* In case of flaring for R410A with the conventional
flare tool, pull the tool out approx. 0.5 mm more than
that for R22 to adjust it to the specified flare size.
The copper pipe gauge is useful for adjusting the
projection margin size.
– 9 –
Tightening of connecting part
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1
Align the centers of the connecting pipes
and fully tighten the flare nut with your
fingers. Then fix the nut with a wrench as
shown in the figure and tighten it with a
torque wrench.
Half union or packed valve
Externally
threaded side
Fix with wrench.
2
As shown in the figure, be sure to use two
wrenches to loosen or tighten the flare nut of
the valve on the gas side. If you use a single
crescent, the flare nut cannot be tightened to
the required tightening torque.
On the other hand, use a single crescent to loosen
B
or tighten the flare nut of the valve on the liquid
side.
Outer dia. of copper pipe
6.4 mm (dia.)
Conventional
tool used
9.5 mm (dia.)
R410A
12.7 mm (dia.)
1.0 to 1.5
Cap
+0
A
Tightened
–0.4
9.9
Wrench for fixing
13.2
16.6
CAUTION
• Do not put the crescent wrench on the cap.
The valve may break.
• If applying excessive torque, the nut may break
according to some installation conditions.
Flare nut
Internally
threaded side
Tighten with torque
wrench.
• After the installation work, be sure to check for gas
leaks of the pipe connections with nitrogen.
• Pressure of R410A is higher than that of R22
(Approx. 1.6 times).
(Unit: N•m) Therefore, using a torque wrench, tighten the flare
pipe connecting sections that connect the indoor /
Tightening torque
outdoor units at the specified tightening torque.
Incomplete connections may cause not only a gas
14 to 18 (1.4 to 1.8 kgf•m)
leak, but also trouble with the refrigeration cycle.
34 to 42 (3.4 to 4.2 kgf•m)
49 to 61 (4.9 to 6.1 kgf•m) Do not apply refrigerant oil to the flared surface.
Flare nut
Wrench for work
Loosened
Valve at gas side
In correct
18-EN