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Condensate drain pipe insulation
The condensate drain system piping must be insulated to prevent sweating after the leak check is performed. All
material used in the condensate drain system must comply with applicable codes and regulations covering
materials installed in the ceiling plenum area.
To cover the pipe and the indoor unit with a heat
insulator, do not make a space between them.
Pipe insulator
(locally procured)
Fix the insulator with adhesive tape
Pipe insulator
(indoor unit side)
1” drain pipe
(locally procured)
6
Refrigerant piping
CAUTION
When the refrigerant pipe is long, provide support
brackets at intervals of 8’2” to 9’10” (2.5 to 3 m) to clamp
the refrigerant pipe. Otherwise, abnormal sound may be
generated.
Use the flare nut attached with the indoor unit or R410A
flare nut.
Permissible piping length and
height difference
They vary depending on the outdoor unit. For details,
refer to the Installation Manual attached to the outdoor
unit.
Pipe size
Unit: in (mm)
Connecting refrigerant piping
Flaring
1
Cut the pipe with a pipe cutter.
Remove burrs completely. (Remaining burrs may
cause gas leakage.)
2
Insert a flare nut into the pipe, and flare the
pipe.
Use the flare nut provided with the unit or the one
used for the R410A refrigerant. The flaring
dimensions for R410A are different from the ones
used for the conventional R22 refrigerant. A new
flare tool manufactured for use with the R410A
refrigerant is recommended, but the conventional
tool can still be used if the projection margin of the
copper pipe is adjusted to be as shown in the
following table.
Projection margin in flaring: B
Unit: in (mm)
Flaring diameter size: A
Unit: in (mm)
* In case of flaring for R410A with the conventional
flare tool, pull it out approx. 0.02” (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.
• The sealed gas was sealed at the atmospheric
pressure so when the flare nut is removed, there will
no “whooshing” sound: This is normal and is not
indicative of trouble.
• Use two wrenches to connect the indoor unit pipe.
Model MMD-
Pipe size
Gas side
Liquid side
AP007 to AP012
3/8” (9.5)
1/4” (6.4)
AP015 to AP018
1/2” (12.7)
1/4” (6.4)
AP021 to AP048
5/8” (15.9)
3/8” (9.5)
Outer dia. of
copper pipe
R410A tool used
Conventional
tool used
1/4” to 5/8”
(6.4 to 15.9)
0 to 0.02”
(0 to 0.5)
0.04” to 0.06”
(1.0 to 1.5)
Outer dia. of copper pipe
A
+0
–0.02” (0.4)
1/4” (6.4)
0.36” (9.1)
3/8” (9.5)
0.52” (13.2)
1/2” (12.7)
0.65” (16.6)
5/8” (15.9)
0.78” (19.7)
B
A
Work using double spanner
17-EN
18-EN
+00EH99881801_01EN.book Page 9 Friday, November 25, 2011 10:23 AM
