Specifications

164
(d) Drain Piping
1) Drain piping should always be in downhili grade (1/50 ~ 1/100) and avoid riding across and elevation or making traps.
2) When connecting the drain pipe to unit, pay sufficient attention not to applay excess force to the piping on the unit side.
Also, fix the piping at a point as close as possible to the unit.
3) For drain pipe, use hard PVC general purpose pipe VP-25(I.D.1”) which
can be purchased locally. When connecting, insert a PVC pipe end se-
curely into the drain socket before tightening securely using the attached
drain hose and clamp. Adhesive must not be used connection of the drain
socket and drain hose (accessory).
4) When consturcting drain piping for several units, position the com-
mon 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
purpes.
5) Be sure to provide heat insulation to hard PVC pipes of indoor
placement.
6) Do not ever provide an air vent.
7) The height of the drain head can be elevated up to a point 700 mm ablve the
ceiling and, when an obstacle exisits 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 too high, 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 sketeh below.
8) 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.
9) The purpose of drain hose is to absorb minute discrepancy of the unit or the
drain piping occurred when they are installed. Therefore, when it is bent
intentionally or used under expanded condition, it may be damaged and re-
sult in water leakage.
Drainage test
1 Conduct a drainage test after completion of the electrical work.
2 During the trial, make sure that drain flows properly through the piping and that no water leaks from connections.
3 In case of a new building, conduct the test before it is furnished with the ceiling.
4 Be sure to conduct this test even when the unit is installed in the heating season.
Forced drain pump operation
1 Turn on dip switch 5-3 on the PCB of the indoor unit. The drain pump operates continuously.
2 After the test, be sure to turn off the dip switch.
(If the electrical work has not been completed, connect a convex coupling to the drain
pipe to provide a supply port and confirm the draining status of the piping system.)
Procedures
1 Supply about 1000 cc of water to the unit through the air outlet by using a feed water
pump.
1.5 m ~ 2 m
Suspension
bolts
A downhill grade
of 1/100 or more
Heat
insulation
Avoid riding across an elevation
Air vent
Keep free from traps
Do not pipe under water
Drain hose
Stage
difference
part
Drain socket
Drain socket
Clamp
(accessory)
Pipe cover (large)
[for insuation]
(accessory)
VP25 joint
(field purchased)
Drain hose
(accessory)
Indoor unit
Adhesion
Pipe cover (small)
[for insuation]
(accessory)
Pipe cover
[for insuation]
(field purchased)
VP25
(field purchased)
Secure the elevation as high as possible
(approx. 100 mm)
VP30
VP25 joint
(field purchased)
A downhill grade of
1/100 or more
295 ~ 325 mm 100 mm or less
Drain hose
700 mm or less
Put the tip of the feed water pump
in the drain pan of the unit body
• Good piping
• Improper piping
Pour water into a convex joint
If the electrical work has not been completed, connect a convex joint in the
drain pipe connection to provide a water inlet.
Then, check if water leaks from the piping system and that drain flows
through the drain pipe normally.