Mitsubishi Heavy Industries 112KXE6 Service Manual Download

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128

④

Installation of indoor unit (continued)

⑥

Drain pipe

⑤

Refrigerant pipe

6. Make sure to install the indoor unit horizontally. Confirm the

levelness of the indoor unit with a level gauge or transpar-
ent hose filled with water. Keep the height difference at
both ends of the indoor unit within 3mm.

7. Tighten four upper nuts and fix the unit after height and

levelness adjustment.

Caution

●

Do not adjust the height by adjusting upper nuts. It will cause unexpected stress on the indoor
unit and it will lead to deformation of the unit, failure of attaching a panel, and generating noise
from the fan.

●

Make sure to install the indoor unit horizontally and set the gap between the unit underside and
the ceiling plane properly. Improper installation may cause air leakage, dew condensation,
water leakage and noise.

●

Even after decorative panel attached, still the unit height can be adjusted finely. Refer to the
installation manual for decorative panel for details.

●

Make sure there is no gap between decoration panel and ceiling surface, and between decora-
tion panel and the indoor unit. The gap may cause air leakage, dew condensation and water
leakage.

●

In case decorative panel is not installed at the same time, or ceiling material is installed after
the unit installed, put the cardboard template for installation attached on the package (packing
material of cardboard box) on the bottom of the unit in order to avoid dust coming into the indoor
unit.

Caution

●

Use the new refrigerant pipe.

When re-using the existing pipe system for R22 or R407C, pay attention to the following items.

・

Change the flare nuts with the attached ones (JIS category 2), and reprocess the flare parts.

・

Do not use thin-walled pipes.

●

Use phosphorus deoxidized copper alloy seamless pipe (C1220T specified in JIS H3300) for
refrigeration pipe installation.

In addition, make sure there is no damage both inside and outside of the pipe, and no harmful
substances such as sulfur, oxide, dust or a contaminant stuck on the pipes.

●

Do not use any refrigerant other than R410A.

Using other refrigerant except R410A (R22 etc.) may degrade inside refrigeration oil. And air
getting into refrigeration circuit may cause over-pressure and resultant it may result in bursting,
etc.

●

Store the copper pipes indoors and seal the both end of them until they are brazed in order to
avoid any dust, dirt or water getting into pipe. Otherwise it will cause degradation of refrigeration
oil and compressor breakdown, etc.

●

Use special tools for R410 refrigerant.

Work procedure

1. Remove the flare nut and blind flanges on the pipe of the indoor unit.

※　

Make sure to loosen the flare nut with holding the nut on pipe side with a spanner and giving torque

to the nut with another spanner in order to avoid unexpected stress to the copper pipe, and then
remove them.

(Gas may come out at this time, but it is not abnormal.)

●　

Pay attention whether the flare nut pops out. (as the indoor unit is sometimes pressured.)

2. Make a flare on liquid pipe and gas pipe, and connect the refrigeration pipes on the indoor unit.

※

Bend the pipe with as big radius as possible and do not bend the pipe repeatedly. In

addition, do not twist and crush the pipes.

※

Do a flare connection as follows:

●　

Make sure to loosen the flare nut with holding the nut on pipe side with a spanner and giving

torque to the nut with another spanner in order to avoid unexpected stress to the copper
pipe, and then remove them.

●　

When fastening the flare nut, align the refrigeration pipe with the center of flare nut, screw

the nut for 3-4 times by hand and then tighten it by spanner with the specified torque
mentioned in the table below. Make sure to hold the pipe on the indoor unit securely by a
spanner when tightening the nut in order to avoid unexpected stress on the copper pipe.

3. Cover the flare connection part of the indoor unit with attached insulation material after a gas

leakage inspection, and tighten both ends with attached straps.

●

Make sure to insulate both gas pipes and liquid pipes completely.

※　

Incomplete insulation may cause dew condensation or water dropping.

4. Refrigerant is charged in the outdoor unit.

As for the additional refrigerant charge for the indoor unit and piping, refer to the installation
manual attached to the outdoor unit.

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.

Indoor unit

hose

Pipe diameter

Tightening torque N·m

6.35

9.52

12.7

15.88

19.05

14 to 18
34 to 42
49 to 61
68 to 82

100 to 120

Strap (Accessory)

Pipe cover (Accessory)

The thickness of insulation should be 20mm or more.

Work procedure
1. Insert the supplied drain hose (the end made of soft PVC) to the step of the drain socket on the indoor unit
and fix it securely with the clamp. Attach the hose clamp to the drain hose around 10mm from the end.

●

Do not apply adhesives on this end.

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.
Do not bend or make an excess offset on the drain hose as shown in the picture.
Bend or excess offset will cause drain 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.

●

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.

Descending slope greater than 1/100

VP-30 or bigger

As wide as possible

(about100mm)

Drain hose

700mm or less

Joint for VP-20

(Prepare on site)

⑥

Drain pipe (continued)

⑩

How to check the dirt of drain pan (Maintenance)

⑦

Wiring-out position and wiring connection

⑧

Panel installation

Drain pump operation

○

In case electrical wiring work finished

Drain pump can be operated by remote controller (wired).

For the operation method, refer to Operation for drain pump in the installation manual for wiring
work.

○

In case electrical wiring work not finished

Drain pump will run continuously when the dip switch“SW7-1” on the indoor unit PCB is turned ON, the Connec-

tor CNB is disconnected, and then the power supply (230VAC on the terminal block

①

and

②

) is turned ON.

Make sure to turn OFF “SW7-1” and reconnect the Connector CNB after the test.

●　

Electrical installation work must be performed according to the installation manual by an
electrical installation service provider qualified by a power provider of the country, and be
executed according to the technical standards and other regulations applicable to electrical
installation in the country.

Be sure to use an exclusive circuit.

●　

Use specified cord, fasten the wiring to the terminal securely, and hold the cord securely in
order not to apply unexpected stress on the terminal.

●　

Do not put both power source line and signal line on the same route. It may cause miscommu-
nication and malfunction.

●　

Be sure to do D type earth work.

●　

For the details of electrical wiring work, see attached instruction manual for electrical wiring
work.

1. Remove a lid of the control box (3 screws) and

the wiring cover (2 screws).

2. Hold each wiring inside the unit and fasten

them to terminal block securely.

3. Fix the wiring with clamps.
4. Install the removed parts back to original place.

●

Attach the panel on the indoor unit after electrical wiring work.

●

Refer to attached manual for panel installation for details.

The method of checking the dirt of drain pan

●

It is possible to check the dirt for inlet of drain pan without detaching the panel.

（

Inspection is not possible when the high efficient filter and option spacer is installed.)

１．

Open the air return grille and remove the panel corner cover on drain pan side.

２．

Remove the cover of inspection window. (1screw)

３．

Check the drain pan from the inspection window.

If the drain pan is very dirty

，

remove the drain pan and clean it.

４．

After checking of the dirty of drain pan, restore the cover of the inspection window

securely. Improper restoration of the cover may cause dew condensation and water
leakage.

Attention for removing drain pan

●

The fixing components have been attached the with drain pan. Pay attention to these
components during installation and removing. Take off the hanging hook after removing
four screws. During the installation of drain pan, fix the drain pan firmly by using four screws
after hanging it up with the fixing hook.

Drain pan
Fixing piece

Remove the screws
Rotate the hook

Panel

Corner cover

Cover of

checking

window

Available checking part

for inlet of drain pan.

Wiring cover

Single Split (PAC) series

Power source side
terminal block

Power source side

terminal block

Power source line clamp

Earth

Remote Controller line

Remote controller line

Signal line clamp

Signal side terminal block

Signal line (Shielded cord)

Earth (Signal line)

⑨

Check list after installation

●

Check the following items after all installation work completed.

Check if;

Expected trouble

Check

The indoor and outdoor units are fixed securely?

Falling, vibration, noise

Inspection for leakage is done?

Insufficient capacity

Insulation work is properly done?

Water leakage

Water is drained properly?

Water leakage

Supply voltage is same as mentioned in the model name plate?

PCB burnt out, not working at all

There is mis-wiring or mis-connection of piping?

PCB burnt out, not working at all

Earth wiring is connected properly?

Electric shock

Cable size comply with specified size?

PCB burnt out, not working at all

Any obstacle blocks airflow on air inlet and outlet?

Insufficient capacity

Supporting metal

No bump

No trap

Not touching the water

Trapped air will

generate noises.

Checking window

for draining

Drain plug

Wiring between indoor and outdoor unit

Air vent

Insulation material

1.5m ~ 2m

Descending slope greater than 1/100

Pipe cover (small)

(For insulation)

(Accessory)

Drain socket

The step part Drain hose

No adhesive allowed

Unit

pipe cover (big)

(For insulation)

(Accessory)

Joint for VP-20

(Prepare on site)

Drain socket

Connect

VP-20

(Prepare on site)

Pipe cover (small)

(For insulation)

(Prepare on site)

Drain hose

(Accessory)

Clamp

(Accessory)

Fasten the screw securely

Hose clamp

Drain hose

Drain socket

Metal plate

10mm

Over 20mm

295 to 325mm

100 or less

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.

Drain up

●　

The position for drain pipe outlet can be raised up to 700mm 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.

Drain test

●　

After installation of drain pipe, make sure that drain system work in good condition and no

water leakage from joint and drain pan. Check if the motor sound of drain pump is normal

or not.

●　

Do drain test even if installation of heating season.

●　

For new building cases, make sure to complete the test

before hanging the ceiling.

1. Pour water of about 1000cc into the drain pan in the

indoor unit by pump so as not to get the electrical