En-4
B
J
S
U
Ø
P
Ø
L
V
A
G
Q
FD
O
N
M
E
K
H
W
C
X
I
R
Bottom
view
Air
Air
(For liquid pipe)
1.1 in (28 mm)
(For gas pipe)
.750 in (19.05 mm)
female pipe thread
Primary and secondary
drain ports
3.3.2. Leveling
Install the unit so that it is level or pitches slightly –(1/8 in) – toward the condensate drain
connection.
1/8 (3) or
less
Level
(Front)
(Front)
(Right side)
(Right side)
PROHIBITED
Drain
connection
Unit: in (mm)
1/8 (3) or
less
Do not install this unit horizontally.
PROHIBITED
3.3.3. Mounting the duct
CAUTION
To prevent people from touching the parts inside the unit, be sure to install grilles on the
inlet and outlet ports. The grilles must be designed in such a way that cannot be removed
without tools.
The external static pressure is as follows.
ARUV12TLAV: 0.1 to 0.7 in WG (25 to 175 Pa)
ARUV18/24/30/36/48/60TLAV: 0.1 to 0.8 in WG (25 to 200 Pa)
If an intake duct is installed, take care not to damage the temperature sensor (the
temperature sensor is attached to the intake port
fl
ange).
Be sure to install the air
fi
lter in the air inlet. If the air
fi
lter is not installed, the heat
exchanger may be clogged and its performance may decrease.
Placing unit in duct work
• Utilize
fl
exible transitions on supply and return connections to reduce noise and vibration
transmission to the structure.
• When the connecting return air duct is smaller than the coil inlet opening, construct the
transition piece so that the vertical and horizontal dimensions of the transition piece do
not increase more then one inch for every seven inches of length of the transition piece.
• Provide at least three feet of straight duct work preceding the unit inlet.
Duct insulation and vapor proo
fi
ng:
• Properly select and install duct insulation as required by the application.
• All externally insulated duct work must have an adequate vapor seal for summer
operation. This is particularly important where the duct is exposed to highly humid
conditions in such places as attics, vented crawl spaces, unconditioned basements, and
utility rooms. The vapor seal prevents condensation of moisture in the insulating material
and subsequent loss of its insulating value.
4. PIPE INSTALLATION
CAUTION
Be more careful that foreign matter (oil, water, etc.) does not enter the piping than with
refrigerant R410A models. Also, when storing the piping, securely seal the openings by
pinching, taping, etc.
While welding the pipes, be sure to blow dry nitrogen gas through them.
4.1 Selecting the pipe material
CAUTION
Do not use existing pipes from another refrigeration system or refrigerant.
Use pipes that have clean external and internal sides without any contamination which may
cause trouble during use, such as sulfur, oxide, dust, cutting waste, oil, or water.
It is necessary to use seamless copper pipes.
Material : Phosphor deoxidized seamless copper pipes.
It is desirable that the amount of residual oil is less than 0.04 oz. /100 ft. (40 mg /10 m).
Do not use copper pipes that have a collapsed, deformed, or discolored portion (especially
on the interior surface). Otherwise, the expansion valve or capillary tube may become
blocked with contaminants.
Improper pipe selection will degrade performance. As an air conditioner using R410A
incurs pressure higher than when using conventional (R22) refrigerant, it is necessary to
choose adequate materials.
• Thicknesses of copper pipes used with R410A are as shown in the table.
• Never use copper pipes thinner than those indicated in the table even if they are available
on the market.
Thicknesses of annealed copper pipes (R410A)
Pipe outside diameter [in (mm)]
Thickness [in (mm)]
1/4 (6.35)
0.032 (0.80)
3/8 (9.52)
0.032 (0.80)
1/2 (12.70)
0.032 (0.80)
5/8 (15.88)
0.039 (1.00)
3/4 (19.05)
0.047 (1.20)
