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5 Preparation
Installer reference guide
10
ARXM25~35 RXM20~35 RXJ20~3
RXA20~35A3V1B
R32 split series
4P518023-5D – 2019.04
Install the outdoor unit away from direct sea winds.
Example:
Behind the building.
b
c
a
If the outdoor unit is exposed to direct sea winds, install a
windbreaker.
▪ Height of windbreaker≥1.5×height of outdoor unit
▪ Mind the service space requirements when installing the
windbreaker.
a
b
c
d
c
d
a
Sea wind
b
Building
c
Outdoor unit
d
Windbreaker
The outdoor unit is designed for outdoor installation only, and for
ambient temperatures ranging from –10~50°C in cooling mode and
from –20~24°C in heating mode.
5.2.2
Additional installation site requirements
of the outdoor unit in cold climates
Protect the outdoor unit against direct snowfall and take care that the
outdoor unit is NEVER snowed up.
a
b
c
c
d
a
Snow cover or shed
b
Pedestal
c
Prevailing wind direction
d
Air outlet
In any case, provide at least 300 mm of free space below the unit.
Additionally, make sure the unit is positioned at least 100 mm above
the maximum expected level of snow. See
In heavy snowfall areas it is very important to select an installation
site where the snow will NOT affect the unit. If lateral snowfall is
possible, make sure that the heat exchanger coil is NOT affected by
the snow. If necessary, install a snow cover or shed and a pedestal.
5.2.3
Refrigerant piping length and height
difference
What?
Distance
Maximum allowable pipe length
20 m
Minimum allowable pipe length
1.5 m
Maximum allowable height difference
15 m
5.3
Preparing refrigerant piping
5.3.1
Refrigerant piping requirements
INFORMATION
Also read the precautions and requirements in the
"General safety precautions" chapter.
▪
Piping material:
Phosphoric acid deoxidised seamless copper.
▪
Piping diameter:
Liquid piping
Ø6.4 mm (1/4")
Gas piping
Ø9.5 mm (3/8")
▪
Piping temper grade and thickness:
Outer diameter
(Ø)
Temper grade
Thickness (t)
(a)
6.4 mm (1/4")
Annealed (O)
≥0.8 mm
t
Ø
9.5 mm (3/8")
Annealed (O)
(a)
Depending on the applicable legislation and the unit's
maximum working pressure (see "PS High" on the unit
name plate), larger piping thickness might be required.
5.3.2
Refrigerant piping insulation
▪ Use polyethylene foam as insulation material:
▪ with a heat transfer rate between 0.041 and 0.052 W/mK (0.035
and 0.045 kcal/mh°C)
▪ with a heat resistance of at least 120°C
▪ Insulation thickness
Pipe outer diameter
(Ø
p
)
Insulation inner
diameter (Ø
i
)
Insulation thickness
(t)
6.4 mm (1/4")
8~10 mm
≥10 mm
9.5 mm (3/8")
12~15 mm
Ø
i
Ø
i
t
Ø
p
Ø
p
If the temperature is higher than 30°C and the humidity is higher
than RH 80%, the thickness of the insulation materials should be at
least 20 mm to prevent condensation on the surface of the
insulation.