Mitsubishi Heavy Industries SRRM40HENG-L, Handbook, Page: 870 / 1106

FDC-HKX
868
(d) Drain piping
1) Drain piping should always be in a downhill grade (1/50-1/100) and avoid riding across an elevation or makeing traps.
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 close 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 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 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 below. Use VP-30 or thicher pipe for this purpose.
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 may be elevated up to a point 600 mm 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. Therfore, make the height of the drain pipe withing the distance given in
the drawing below.
8) Avoid positioning the drain piping outlet at a place where generation of odor may stimulated. Do not lead the drain piping
direct into a sewer from where sulfur gas may generate.
1.5 m ~ 2m
Suspension
bolts
Heat
insulation
A downhill grade
of 1/100 or more
Air vent
Avoid riding across an elevation
Keep free from traps
Do not pipe under water
Drain socket
Level difference part
Drain hose
Joint for VP-25
(local procurement)
Pipe cover (small)[insulation]
(accessory)
Drain socket
Main
unit
Clamp
(accessory)
Drain hose
(accessory)
Adhesion
VP-25
(local procurement)
Pipe cover [insulation]
(local procurement)
Pipe cover (large)[insulation]
(accessory)
VP30
A downhill grade of
1/100 or more
Secure the elevation as high as possible
(approx. 100 mm)
295 ~ 325
Drain hose
Right above
Joints for VP-25
600 mm (local maximum height of drain head)
●
Good piping
●
Improper piping