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5
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Preparation
Installer reference guide
23
FNA25~60A2VEB(9)
Split system air conditioners
4P550955-3C – 2020.12
Refrigerant piping material
▪
Piping material:
Phosphoric acid deoxidised seamless copper.
▪
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")
12.7 mm (1/2")
(a)
Depending on the applicable legislation and the maximum working pressure of the unit
(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
≥13 mm
12.7 mm (1/2")
14~16 mm
≥13 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.
5.4 Preparing electrical wiring
5.4.1 About preparing electrical wiring
INFORMATION
Also read the precautions and requirements in the
4].