7 | Piping installation
Installer reference guide
36
ARXM50-71+RXM42~71R2V1B + RXP50~71M2V1B + RXA42+50B2V1B +
RXF50+60B2V1B + RXF71A2V1B + RXJ50N2V1B + ARXF50~71A2V1B
R32 split series
4P513661-9J – 2020.05
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") 10~14mm ≥13mm
12.7mm (1/2") 14~16mm ≥10mm
15.9mm (5/8") 16~20mm ≥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
What? Distance
Maximum allowable pipe length 30m
Minimum allowable pipe length 3m
Maximum allowable height distance 20m
7.2 Connecting the refrigerant piping
CAUTION
▪ No brazing or welding on site for units with R32 refrigerant charge during
shipment.
▪ During installation of the refrigeration system, joining of parts with at least one
part charged shall be performed taking into account the following requirements:
ð inside occupied spaces non permanent joints are not allowed for R32 refrigerant
except for site made joints directly connecting the indoor unit to piping. Site
made joints directly connecting piping to indoor units shall be of non permanent
type.
WARNING
▪ Only use R32 as refrigerant. Other substances may cause explosions and
accidents.
▪ R32 contains fluorinated greenhouse gases. Its global warming potential (GWP)
value is 675. Do NOT vent these gases into the atmosphere.
▪ When charging refrigerant, ALWAYS use protective gloves and safety glasses.