Haier 1U71S2SG1FA Service Manual page 98

Drain Piping
Drain piping should always be in a downhill grade (1/50-1/100) and avoid riding across an elevation or making
traps.
Unit Model
AD35S2SM3FA AD35S2SM4FA
AD50S2SM3FA AD50S2SM4FA
AD71S2SM3FA AD71S2SM4FA
(b). When connecting the drain pipe to unit pay suffcient attentionnot
to apply excess force to the piping on the unit side. Also fix the piping
at a point as close as possible to the unit.
(c). For unit without water pump, please refer to the digram and
select drain pipe size according to drain opening inner diameter size.
The drain pipe shall be slant downwards (Greater than 1/100). The
horizontal length of the drain pipe shall be less than 20 m. In case of
long pipe, supports shall be provided every 1.5-2m to prevent wavy
form.
Central piping shall be laid out according to the right figure. Take care
not to apply external force onto the drain pipe connection part.
(d). For unit with water pump drain pipeuse hard PVC general purpose
pipe VP which can be purchased locally. When connecting, insert a
PVC pipe end securely into the drain socket before tightening securely
using the attached drain hose and clamp. Adhesive must not be used
for connection of the drain socket and drain hose (Accessory).
(e). When constructing drain piping for several units, position the
common pipe about 100 mm below the drain outlet of each unit as
shown in the sketch Use VP-30(11/4) or thicker pipe for this purpose
(f). The hard PVC pipe put indoor side should be heat insulated. Do
not ever provide an air vent.
(g). The height of the drain head can be elevated up to a point
500mm above the ceiling, and when an obstacle exists in the ceiling
space, elevate the piping to avoid the obstacle using an elbow or
corresponding gadget. When doing this, if the stretch for the needed
height is higher than 500 mm, the back-flow quantity of drain at the
event of interruption of the operation gets too much and it may cause
overflow at the drain pan. Therefore, make the height of the drain pipe
within the distance given in the sketch below.
(h). Avoid positioning the drain piping outlet at a place where
generation of odor may be stimulated. Do not lead the drain piping
direct into a sewer from where sulfur gas may generate.
The Size of Drain Opening
95
ø25mm