7 | Piping installation
Installer reference guide
35
2(A)MXM40+50 + 2(A)MXF40+50
R32 Split series
4P600463-2C – 2020.08
7.1.2 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
0.045kcal/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)
6.4mm (1/4") 8~10mm ≥10mm
9.5mm (3/8") 12~15mm ≥13mm
12.7mm (1/2") 14~16mm ≥13mm
If the temperature is higher than 30°C and the humidity is higher than RH80%, the
thickness of the insulation materials should be at least 20 mm to prevent
condensation on the surface of the insulation.
7.1.3 Refrigerant piping length and height difference
The shorter the refrigerant piping, the better the performance of the system.
The piping length and height differences must comply with the following
requirements.
Model Minimum required space
Class 40 1.2m
2
Class 50 1.8m
2
Shortest allowable length per room is 3m.
Refrigerant piping length to each indoor unit ≤20m
Refrigerant piping total length ≤30m
Height difference
outdoor-indoor
Height difference indoor-
indoor
Outdoor unit installed
higher than indoor unit
≤15m ≤7.5m
Outdoor unit installed
lower than at least 1
indoor unit
≤7.5m ≤15m