North American HVAC MOC-12HFN1-MS0W, Service Manual

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Drainage pipe installation
98 Installation
5.2.10 Set the wall conduit
5.2.11 Set the supporter for the pipe.
5.2.12 Locate the pipe and fix it by supporter
 For horizontal refrigerant pipe, the distance between supporters should not be exceed 1m.

For vertical refrigerant pipe, the distance between supporters should not be exceed 1.5m.
5.2.13 Connect the pipe to indoor unit and outdoor unit by using two spanners.
 Be sure to use two spanners and proper torque to fasten the nut, too large torque will damage the
bellmouthing, and too small torque may cause leakage. Refer the following table for different pipe
connection.
Pipe Diameter
Torque Sketch map
(kgf.cm) (N.cm)
1/4" (6.35) 144~176 1420~1720
3/8" (9.52) 333~407 3270~3990
1/2" (12.7) 504~616 4950~6030
5/8" (15.9) 630~770 6180~7540
3/4" (19) 990~1210 9270~11860
6 Drainage pipe installation
Install the drainage pipe as shown below and take measures against condensation. Improperly installation
could lead to leakage and eventually wet furniture and belongings.
6.1 Installation principle
 Ensure at least 1/100 slope of the drainage pipe

Adopt suitable pipe diameter
 Adopt nearby condensate water discharge
6.2 Key points of drainage water pipe installation
6.2.1 Considering the pipeline route and elevation
 Before installing condensate water pipeline, determine its route and elevation to avoid intersection with
other pipelines and ensure slope is straight.
6.2.2 Drainage pipe selection
 The drainage pipe diameter shall not small than the drain hose of indoor unit
 According to the water flowrate and drainage pipe slope to choose the suitable pipe, the water flowrate
is decided by the capacity of indoor unit.
Relationship between water flowrate and capacity of indoor unit
Capacity (x1000Btu) Water flowrate (l/h)
12 2.4
18 4
24 6
30 7
36 8
42 10
48 12
60 14
According to the above table to calculate the total water flowrate for the confluence pipe selection.
For horizontal drainage pipe (The following table is for reference)
PVC pipe Reference value of inner Allowable maximum water flowrate (l/h) Remark