42
SMMS High-Wall Type
Installation Manual
9
REFRIGERANT PIPING
Refrigerant Piping
1.
Use copper pipe with 0.8 mm or more
thickness.
(In case pipe size is dia. 15.9,
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.
REQUIREMENT
When the refrigerant pipe is long, provide support
brackets at intervals of 2.5 to 3m 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
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 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)
Flaring dia. meter size: A (Unit: mm)
* In case of flaring for R410A with the
conventional flare tool, pull it out
(dia.: mm)
MMK-
AP007 to
AP012 type
AP015 to
AP018 type
AP024 type
Gas side
9.5
12.7
15.9
Liquid
side
6.4
6.4
9.5
Outer dia. of
copper pipe
R410A tool used
Conventional
tool used
R410A
R410A
6.4 , 9.5
0 to 0.5
1.0 to 1.5
12.7 , 15.9
Outer dia. of copper pipe
R410A
1
.
9
4
.
6
2
.
3
1
5
.
9
6
.
6
1
7
.
2
1
7
.
9
1
9
.
5
1
B
A
0
-0.4
+
A
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.
SMMS High-Wall Type
Installation Manual
Toshiba
Tightening connection
CAUTION
• Do not apply excessive torque. Otherwise, the
nut may crack depending on the conditions.
▼
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.
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 flare nut as far as possible with your
fingers. Then tighten the nut with a spanner and
torque wrench as shown in the figure.
REQUIREMENT
Tightening with an excessive torque may crack the
nut depending on installation conditions.
Tighten the nut within the specified tightening
torque.
Piping with outdoor unit
• Shape of valve differs according to the outdoor
unit.
For details of installation, refer to the Installation
Manual of the outdoor unit.
Heat insulation
Heat insulation for the pipes should be done
separately for the liquid side and gas side. Because
both of the liquid and gas side pipes become a low
temperature during cooling operation, sufficient
heat insulation should be done to prevent
condensation.
• Heat insulator with a heat resistance of 120°C or
more must be used for the gas side pipe.
• The pipe connection section of the indoor unit
must be heat insulated securely and compactly
with the attached heat insulator.
Airtight test/Air purge, etc.
For airtight test, air purge, addition of refrigerant,
and gas leak check, follow the Installation Manual
attached to the outdoor unit.
Open fully valves of the outdoor
unit
Gas leak check
Check with a leak detector or soap water whether
gas leaks or not, from the pipe connecting section
or cap of the valve.
REQUIREMENT
Use a leak detector manufactured exclusively HFC
refrigerant (R410A, R134a, etc.).
(Unit: N•m)
Outer dia. of copper pipe
Tightening torque
6.4 mm (dia.)
14 to 18 (1.4 to 1.8 kgf•m)
9.5 mm (dia.)
33 to 42 (3.3 to 4.2 kgf•m)
12.7 mm (dia.)
50 to 62 (5.0 to 6.2 kgf•m)
15.9 mm (dia.)
68 to 82 (6.8 to 8.2 kgf•m)
Work using double spanner
Fix with vinyl tape
Heat insulator
(attached)
Local side pipe
+1111050501_01EN_SMMS_HighWall_IM_B5.book Page 14 Wednesday, November 12, 2008 2:45 PM
