DC Inverter Cassette Type Air Conditioner Installation and Operation Manual
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Fig.22
● When connect the pipe to the unit or backout it from the unit, please do use both spanner and torque
wrench. As shown in Fig.22.
● When connect, smear both inside and outside of the are nut with freeze motor oil, screw it by hand and
then tighten it with spanner.
● Refer to Table 4 to check if the wrench had been tightened (too tight would mangle the nut and lead
leakage).
Table 4 the tightening torque needed for tightening nut
Diameter(Inch) Surface thickness(mm) Tightening torque (N·m)
φ1/4 ≥0.5 15-30
φ3/8 ≥0.71 30-40
φ1/2 ≥1 45-50
φ5/8 ≥1 60-65
φ3/4 ≥1 70-75
● Examine the connection pipe to see if it had gas leakage, and then take the treatment of heat insulation, as
shown in the Fig.22.
● Only use median sponge to entwine the wiring interface of the gas pipe and heat preservation sheath of
the gas collection tube.
8.2.7 Drainage hose
1.Install the drain hose
● The diameter of the drain hose should be equal or bigger than the connection pipe’s. (The diameter of
polythene pipe: Outer diameter 25mm Surface thickness ≥1.5mm)
● Drain hose should be short and drooping gradient should at less 1/100 to prevent the formation of air
bubble.
● If drain hose cannot has enough drooping gradient, drain raising pipe should be added.
● To prevent bent of the drain hose, the distance between hoisting stand should is 1 to 1.5m.