Drain Socket; Hard Pvc Pipes Laid Indoor; Drainage Test; Forced Drain Pump Operation - Mitsubishi Heavy Industries FDCA Series Technical Manual

b) Give the drain piping a descending grade (1/50-1/100) and never cre-
ate a bump to go over or a trap.
c) In connecting drain pipes, care must be taken so as not to apply force
to the unit side piping and fix the pipe at a point as close to the unit as
possible.
d) Do not create an air vent under any circumstances.
e) When drain piping is implemented for more than one unit, provide a
collecting main about 100 mm below the units' drain outlets from
which it collects drain. Use a VP-30 or larger pipe for a collecting
main.
f) Do not fail to provide heat insulation at the following two points be-
cause they can cause dew condensation and a resultant water leak.

7) Drain socket

After a drain test is completed, apply a pipe cover (small: accessory)
onto the drain socket, cover the pipe cover (small), the clamp and part of
the drain hose with a pipe cover (large: accessory) and wrap it with a tape
completely without leaving any gaps.
(Cut pipe covers into appropriate shapes)

8) Hard PVC pipes laid indoor

a) Since a drain pipe outlet can be raised up to 700 mm from the ceil-
ing, use elbows, etc. to install drain pipes, it there are obstacles pre-
venting normal drain pipe arrangement. When the drain pipe is raised
at a point far from a unit, it can cause an overflow due to a back flow
of drain upon stoppage, so arrange piping to keep the dimensions
specified in the illustration shown on the left.
b) Install the drain pipe outlet where no odor is likely to be generated.
c) Do not lead the drain pipe into a ditch where the generation of harm-
ful gas such as sulfuric gas or flammable gas is expected. A failure to
observe this instruction may cause such harmful or flammable gas to
flow into the room.

Drainage test

1 Check that water is draining thoroghly during test run, and that there are no water leaks from the joints and the drain pan.
2 The test has to be performed even if the unit is installed in the season when the unit is used for healting.
3 In a new house, perform the test before the ceiling is fitted.
• Using a water pump, pour about 1000 cc of water to the drain pan through
the blowing outlet.
• Check the transparent drain-out section of the drain hose for normal flow
of drainage.
* While observing the noise from the drain motor, test drain operation.
• Take off the drain plug to release the water. After the water is drained, place
the drain pulg back where it was..
* Be careful not to get splashed when pulling the drain plug.

Forced drain pump operation

S Set up from a unit side.
1 Turn power on after selecting the emergency operation mode with a setting on the indoor unit board (SW9-3 ON) and discon-
necting the CnB connector on the board. Then, the drain pump will start a continuous operation 15 seconds later.
(Note: The blower will also start operation in tandem)
2 When a drain test is completed, reinstate the setting to cancel the emergency operation mode (SW9-3 OFF) and plug in the
CnB connector on the board.
(When electrical work is not completed, connect a convex joint to the drain pipe joint area, arrange an inlet and check leaks and
drain connections of the pipe)
86
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Suspension
1.5 m ~ 2 m
bolts
Insulation Desceding slope
material greater than 1/100
Trapped air will
generate noises.
As wide as possible
(about 100 mm)
Desceding slope
VP30
greater than 1/100
295 ~ 325 mm 100 mm or less
Drain hose
Joint for VP-25
(not included)
Put the tip of the feed water pump
in the drain pan of the unit body
Drain plug