Mitsubishi Heavy Industries SRK25GZ-L1 Handbook page 865

(h) Drain piping
1) Drain piping should always be in a downhill grade (1/50-1/100) and avoid riding across an elevation or making traps.
● Good piping
Suspension
bolts
1.5 m ~ 2m
Heat
A downhill grade
insulation
of 1/100 or more
2) When connecting the drain pipe to the unit, pay suffcient attention not to apply excess force to the piping on the unit side.
Also, fix the piping at a point as possible to the unit.
3) For drain pipe, use hard PVC general purpose pipe VP-25 which can be purchased
locally. When connecting, insert a PVC pipe end securely into the drain socket be-
fore 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 constructing drain piping for several units, position the common pipe about 100mm below the drain outlet of each unit
as shown in the sketch below. Use VP-30 or thicker pipe for this purpose.
5) Be sure to provide heat insulation to hard PVC pipes of indoor placement.
6) Do not ever provide an vent.
7) The height of the drain head may be elevated up to a point 600mm from the bottom of unit 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 too high, the back-flow quantity of drain at the time 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 withing the distance given in
the drawing below.
295 ~ 325
Drain hose
8) Avoid positioning the drain piping outlet at a place where ganeration of odor may be stimulated. Do not lead the drain piping
direct into a sewer from where sulfur gas may ganerate.
● Improper piping
Air vent
Pipe cover (small)[insulation]
(accessory)
Right above
Joints for VP-25
Drain socket
Pipe cover (large)[insulation]
(accessory
Main
unit
Drain hose
Clamp
Drain socket
(accessory)
(accessory)
Secure the elevation as high as possible
(approx. 100 mm)
A downhill grade
of 1/100 or more
FDC-HKX
Avoid riding across an elevation
Keep free from traps
Do not pipe under water
Level difference part
Drain hose
Joint for VP-25
(local procurement)
VP-25
(local procurement)
Pipe cover [insulation]
(local procurement)
Adhesion
VP-30
863