Gree GWHD(28)NK3FO - Page 45

43
Installation and Maintenance
Service Manual
Table 3
Allowable LengthRefrigerant Pipe
36 42 36 42
Total Length(m) 70 80 L
1
+L
2
+L
3
+ L
4
L
1
+L
2
+L
3
+ L
4
+ L
5
Max. Length for Single Unit(m) 20 25 L
X
Max.
installation
altitude
Outdoor unit
and indoor unit
15 15 H1
Indoor unit
and indoor unit
7.5 7.5H2
Table 4: Dimension of the Refrigerant Pipe of the Indoor Unit unit
˖
mm
Capacity Level of the Indoor Unit Gas Pipe Liquid Pipe
09,12 Φ9.52Φ6.35
18 Φ12.7Φ6.35
21,24 Φ15.9Φ9.52
d.Piping between the Indoor and Outdoor Units
1) Refer to Fig.6 for the moments of torque for tightening screws.
3) After that, tighten the screw by the torque wrench unit it clatters (as shown in Fig.6).
4) The bending degree of the pipe can not be too small; otherwise it will crack. And please use a pipe tube benderr to
bend the pipe.
5) Wrap the exposed refrigerant pipe and the joints by sponge and then tighten them with the plastic tape.
Fig.6
Table 5:Moments of Torque for Tightening Screws
Diameter Wall Thickness
˄
mm
˅
Moment of Torque
Φ6.35mm ≥0.5 15-30(N·m)
Φ9.52mm ≥0.71 30-40(N·m)
Φ12.7mm ≥1 45-50(N·m)
Φ15.9mm ≥1 60-65(N·m)
Pipe
Flare Nut
Pipe
Torque Wrench
Ordinary
the outlet pipe of the indoor unit takes precedence. A reducing nipple shall be installed at the joint of the outdoor unit so as to
make the joint of the outdoor unit compatible with that of the indoor unit.