Mitsubishi Electric FDT125VNVF Technical Manual page 233

⑦Drain pipe
Caution
● Install the drain pipe according to the installation manual in order to drain properly.
Imperfection in draining may cause flood indoors and wetting the household goods, etc.
● Do not put the drain pipe directly into the ditch where toxic gas such as sulfur, the other harmful
and inflammable gas is generated. Toxic gas would flow into the room and it would cause
serious damage to user's health and safety (some poisoning or deficiency of oxygen).
In addition, it may cause corrosion of heat exchanger and bad smell.
● Connect the pipe securely to avoid water leakage from the joint.
● Insulate the pipe properly to avoid condensation drop.
● Check if the water can flow out properly from both the drain outlet on the indoor unit and the end
of the drain pipe after installation.
● Make sure to make descending slope of greater than 1/100 and do not make up-down bend
and/or trap in the midway. In addition, do not put air vent on the drain pipe. Check if water is
drained out properly from the pipe during commissioning. Also, keep sufficient space for
inspection and maintenance.
Work procedure
1. Make sure to insert the drain hose (the end mode of soft PVC) to the end of the step part of
drain socket.
Attach the hose clamp to the drain hose around 10mm from the end, and fasten the screw
within 5mm left to the nut.
●Do not apply adhesives on this end.
●Do not use acetone-based adhesives to connect to the drain socket.
Stage difflernce part
Drain socket
Drain hose
Fasten the screw within
5 mm left to the nut.
Drain hose
Hose clamp
Drain socket
10mm
Metal plate
2. Prepare a joint for connecting VP-20 pipe, adhere and connect the joint to the drain hose (the
end made of rigid PVC), and adhere and connect VP-20 pipe (prepare on site).
※As for drain pipe, apply VP-20 made of rigid PVC which is on the market.
● Make sure that the adhesive will not get into the supplied drain hose.
It may cause the flexible part broken after the adhesive is dried up and gets rigid.
● The flexible drain hose is intended to absorb a small difference at installation of the unit or
drain pipes. Intentional bending, expanding may cause the flexible hose broken and water
leakage.
3. Make sure to make descending slope of greater than 1/100 and do not make up-down bend
and/or trap in the midway.
●Pay attention not to give stress on the pipe on the indoor unit side, and support and fix the
pipe as close place to the unit as possible when connecting the drain pipe.
●Do not set up air vent.
Supporting metal
1.5m~2m
Air vent
Insulation material
Descending slope greater than 1/100
●When sharing a drain pipe for more
than one unit, lay the main pipe 100mm
below the drain outlet of the unit. In
addition, select VP-30 or bigger size for
main drain pipe.
4. Insulate the drain pipe.
● Be sure to insulate the drain socket and rigid PVC pipe installed indoors otherwise it may
cause dew condensation and water leakage.
※ After drainage test implementation, cover the drain socket part with pipe cover (small
size), then use the pipe cover (big size) to cover the pipe cover (small size), clamps and
part of the drain hose, and fix and wrap it with tapes to wrap and make joint part
gapless.
Pipe cover (big) (For insulation)
(Accessory)
VP20 joint (Prepare on site)
Unit
VP20
Drain hose
Adhesion
(Prepare on site)
(Accessory)
Drain socket
Clamp (Accessory)
Pipe cover (small)
Pipe cover (small)
(For insulation)
(For insulation) (Accessory)
(Prepare on site)
Trapped air will
No bump
generate noises.
No trap
Not touching the water
As wide as possible
(about100mm)
VP-30 or bigger
Descending slope greater than 1/100
-
⑦Drain pipe (continued)
Drain up
● The position for drain pipe outlet can be raised up to 600mm above the ceiling. Use elbows
for installation to avoid obstacles inside ceiling. If the horizontal drain pipe is too long before
vertical pipe, the backflow of water will increase when the unit is stopped, and it may cause
overflow of water from the drain pan on the indoor unit. In order to avoid overflow, keep the
horizontal pipe length and offset of the pipe within the limit shown in the figure below.
290-325
Otherwise, the construction point makes it same as drain pipe construction.
Drain test
1. Conduct a drain test after completion of the electrical work.
2. During the trail, 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.
Procedures
1. Supply about 1000 cc of water to the unit through the air outlet by using a feed water pump.
2. Check the drain while cooling operation.
Insert water supply hose
for 20mm ~ 30mm to
supply water.
(Insert hose facing
toward bottom.)
Remove grommet
Make sure to Install
it back after test.
Outline of bottom drain piping work
● If the bottom drain piping can be done with a
descending gradient (1/50-1/100), it is possible to
connect the pipes as shown in the drawing below.
Uncoupling the drain motor connector
● Uncouple the connector CNR for the drain motor as
illustrated in the drawing on the right.
(
Note: If the unit is run with the connector coupled,
drain water will be discharged from the upper
drain pipe joint, causing a water leak.
232
-
'12 • PAC-T-174
100 or less
Attached drain hose clamp
Pour water into a convex joint
Drain
Main
piping
unit
Drain situation can be checked with transparent socket.
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.
Connecting port of top drain pipe
Standard hard polyvinyl
chloride pipes
Connecting port of bottom drain pipes
Insulating material
Rubber stopper (to be removed)
)
PJG012D001C
P.C. board
B