Daikin 3MKS50ESG User manual

REMOVAL
PROCEDURE
SERVICE MANUAL
4.0/5.0/5.2/5.8/6.8 kW Class
Outdoor Unit
Inverter
Multi Type
Si121291EC

Service Manual
Removal Procedure
Outdoor Unit
zCooling Only zHeat Pump
3MKS50ESG 3AMX52E4V1B
3MKS50FSG 3MXS40K3V1B
3MKS58KVM 3MXS52E4V1B
3MKS58LVMA 3MXS52KVM
3MKS58LVMA9
3MXS52LVMA
3MKS68LVMA 3MXS52LVMA9
3MKS68LVMA9
3MXS68G3V1B
3MXS68LVMA
3MXS68LVMA9
4MXS68F3V1B

Si121291EC
Removal Procedure 1
Table of Contents
1. Outer Panels ...........................................................................................2
2. Electrical Box ..........................................................................................4
3. PCBs .......................................................................................................9
4. Fan Motor..............................................................................................12
5. Sound Blankets .....................................................................................13
6. Coils / Thermistors ................................................................................16
7. Distributor..............................................................................................18
8. Four Way Valve.....................................................................................19
9. Compressor...........................................................................................20
Note: The illustrations may be slightly different depending on the model.
The illustrations are for heat pump models as representative.

Outer Panels Si121291EC
2Removal Procedure
1. Outer Panels
Warning Be sure to wait for 10 minutes or more after turning off all power supplies before
disassembling work.
Step Procedure Points
1Remove the 4 screws
and remove the top
panel.
The illustrations are for 3-
room models as
representative.
2Remove the 6 screws
of the front panel.
3Remove the screw of
the shield plate.
4Unfasten the 2 hooks
and remove the shield
plate.
5Unfasten the 4 hooks
and remove the front
panel.
Front panel
(R17891)
Top panel
Shield plate
(R11204)
(R17754)
Hook
Hook
(R17755)
Hook

Si121291EC Outer Panels
Removal Procedure 3
6Remove the 4 screws
and remove the
discharge grille.
7
8
Remove the 2 screws
of the stop valve cover.
Slide the stop valve
cover downward and
remove it.
When reassembling, make
sure to fit the 5 hooks.
Step Procedure Points
Discharge grille
(R12902)
(R11206)
Stop valve cover
(R5506)
(R5508)

Electrical Box Si121291EC
4Removal Procedure
2. Electrical Box
Warning Be sure to wait for 10 minutes or more after turning off all power supplies before
disassembling work.
Step Procedure Points
1. Disconnect the
harnesses.
1Peel off the fixing tape.
2Unfasten the 4 hooks
and remove the
electrical box cover.
3Detach the clamp and
disconnect the
connector [S70].
[S70]: fan motor
When reassembling, insert
the clamp into either hole as
below.
Some models have no ferrite
core for the harness of [S70].
4Release the fan motor
lead wire from the
hooks.
(R18379)
Electrical box cover
Fixing tape
Hook
Hook
(R17166)
[S70]
For the ferrite
core of fan
motor harness
(R17167)
Fan motor
lead wire
(R17168)

Si121291EC Electrical Box
Removal Procedure 5
5Disconnect the
connectors for the
electronic expansion
valve coil.
[S20] (white) : room A
[S21] (red) : room B
[S22] (blue) : room C
The 4-room model has
[S23] (yellow) for room D.
When reassembling, insert
the clamp of the electronic
expansion valve coil ASSY
into either hole as below.
6Pull out the clamp.
7Disconnect the
connector [S40].
[S40] : overload protector
8 Pull out the clamp with
pliers.
9Disconnect the relay
connector of the
compressor.
Step Procedure Points
(R18380)
Clamp
[S20] [S21] [S22]
For the electronic expansion
valve coil
(R20759)
(R5521)
[S40]
Clamp
(R12904)
Partition
plate
(R5522)

Electrical Box Si121291EC
6Removal Procedure
10 Disconnect each
connector.
[S90] : thermistors
[S92] : gas pipe thermistors
[S93] : liquid pipe thermistors
When reassembling, insert
each clamp of the thermistor
harnesses into the holes as
below.
50/58 class
3MXS52KVM, 3MXS52LVMA(9)
40/68 class
3AMX52E4V1B, 3MX52E4V1B
11 Disconnect the
connector [S80].
[S80] : four way valve coil
The cooling only models
have no harness for [S80].
12 Pull out the clamp of the
thermistor lead wire.
Step Procedure Points
(R5523)
[S90] [S92] [S93]
(R20760)
For [S90]
For [S92]
For [S93]
(R20761)
For [S90]
For [S92]
For [S93]
(R5526)
[S80]
Thermistor lead wire
(R18635)
Fixing position for the
thermistor harness
When reassembling, insert
the clamp into the small
hole.

Si121291EC Electrical Box
Removal Procedure 7
2. Remove the electrical
box.
1Remove the 2 screws
of the earth / ground
wires.
2Remove the screws on
the terminal board and
disconnect all the
connecting wires and
the power supply wire.
3Remove the 2 screws
and remove the wire
fixture.
4Detach the outdoor
temperature thermistor.
5Remove the screw on
the right side of the
electrical box.
Step Procedure Points
(R20762)
Earth /
ground
wire
(R17759)
Wire fixture
(R5533)
(R17893)

Electrical Box Si121291EC
8Removal Procedure
6Remove the screw of
the electrical box.
7Lift up and remove the
electrical box.
Step Procedure Points
(R17760)

Si121291EC PCBs
Removal Procedure 9
3. PCBs
Warning Be sure to wait for 10 minutes or more after turning off all power supplies before
disassembling work.
Step Procedure Points
1. Remove the service
monitor PCB.
1Disconnect the
connectors [S52]
[S102] from the service
monitor PCB.
2Unfasten the upper
hook and remove the
service monitor PCB.
2. Remove the main PCB.
1Remove the screw of
the terminal board and
open it.
(R18805)
[S102]
[S52]
Hook
Service monitor PCB
(R18381)
Hook
(R17896)
Terminal board
(R5539)

PCBs Si121291EC
10 Removal Procedure
2Disconnect the
connectors for the
terminal board on the
right side.
[AC1] [AC2] : power supply
[S10] : transmission
3Disconnect the 2
connectors for the
reactor on the left side.
4Remove the 3 screws
of the main PCB.
5Release the 4 hooks
and lift up the main
PCB.
6Release the relay
harness for the
compressor from the
hook.
Step Procedure Points
[AC1] (brown)[AC2] (blue)[S10]
(R20763)
(R5544)
[HR2]
[HR1]
Reactor
Main PCB
(R17763)
Hook Hook
(R5548)
Hook

Si121291EC PCBs
Removal Procedure 11
7Remove the main PCB. In working, be careful not to
break the main PCB.
The main PCB and the
radiation fin are adhered to
one another.
8Remove the 2 screws
and remove the
radiation fin.
When reassembling, make
sure to use the silicon
grease.
9Remove the 3 screws
and remove the reactor.
Step Procedure Points
(R5549)
Clamp for reactor harness
(R11207)
(R5553)
Radiation fin
Reactor
(R11208)

Fan Motor Si121291EC
12 Removal Procedure
4. Fan Motor
Warning Be sure to wait for 10 minutes or more after turning off all power supplies before
disassembling work.
Step Procedure Points
1Remove the 2 screws
and remove the fan
motor fixing plate.
When reassembling, fit the
lower hooks.
2Remove the nut and
remove the outdoor fan.
Nut size: M6
When reassembling, align
the mark of the outdoor
fan with the D-cut section of
the motor shaft.
When reassembling, put the
fan motor lead wire through
the back of the fan motor so
as not to be entangled with
the outdoor fan.
3Open the 2 hooks and
release the fan motor
lead wire.
4Remove the 4 screws
and remove the fan
motor.
Fan motor fixing plate
(R12908)
(R5564)
(R17764)
Nut
D-cut
mark
Outdoor fan
10 mm
(0.39 inch)
(R18954)
Lead wire Outdoor fan
(R12215)
(R17765)
Hook
(R12913)
Fan motor

Si121291EC Sound Blankets
Removal Procedure 13
5. Sound Blankets
Warning Be sure to wait for 10 minutes or more after turning off all power supplies before
disassembling work.
Step Procedure Points
1. Remove the right side
panel.
1Remove the 3 screws
of the right side panel.
2Remove the 2 screws
on the back.
3Remove the protection
rubber.
There is a hook on the back.
4Lift up and remove the
right side panel.
(R12915)
Right side panel
(R5571)
Protection rubber
(R18806)
Hook
(R5573)

Sound Blankets Si121291EC
14 Removal Procedure
2. Remove the partition
plate.
1Remove the 2 screws
of the partition plate.
2Detach the clamp of the
relay harness for the
compressor.
3Lift up and remove the
partition plate.
When reassembling, make
sure to fit the lower hook of
the partition plate.
Step Procedure Points
(R5575)
Partition plate
(R5576)
(R5577)
(R5580)

Si121291EC Sound Blankets
Removal Procedure 15
3. Remove the sound
blankets.
Since the piping ports on the
sound blanket are torn
easily, remove the blanket
carefully.
The shape of the sound
blankets differs depending
on the model.
1Remove the sound
blanket (top upper).
2Remove the sound
blanket (top inner).
3Open the sound blanket
(outer) and pull it out.
4Open the sound blanket
(inner) and pull it out.
Step Procedure Points
Sound blanket (top upper)
(R5579)
(R5582)
Sound blanket (top inner)
Sound
blanket
(outer)
(R17766)
(R5584)
Sound blanket
(inner)

Coils / Thermistors Si121291EC
16 Removal Procedure
6. Coils / Thermistors
Warning Be sure to wait for 10 minutes or more after turning off all power supplies before
disassembling work.
Step Procedure Points
1Pull out the electronic
expansion valve coils.
2Remove the screw and
remove the four way
valve coil.
The cooling only models
have no four way valve coil.
3Open the putty and
remove the liquid pipe
thermistors.
When reassembling, meet
the edge of the thermistor
and the fixture.
Electronic
expansion
valve coil
(R5588)
(R5589)
Four way
valve coil
Liquid pipe
thermistor
(R11184)

Si121291EC Coils / Thermistors
Removal Procedure 17
4Pull out the gas pipe
thermistors.
Be careful not to lose the
clip.
The positions of the clamp
and outdoor heat exchanger
thermistor differ depending
on the model.
When reassembling, meet
the edge of the thermistor
and the fixture.
5
6
Cut the clamp.
Pull out the outdoor
heat exchanger
thermistor.
7Remove the discharge
pipe thermistor.
8Remove the assembly
of thermistors.
Step Procedure Points
Gas pipe
thermistor
(R5591)
Clip
(R5619)
Outdoor heat
exchanger thermistor (R17171)
Clamp
(R18807)
Discharge pipe thermistor
Fixture
Discharge pipe
thermistor
Outdoor heat
exchanger
thermistor
Outdoor
temperature
thermistor
Connector
(R5594)

Distributor Si121291EC
18 Removal Procedure
7. Distributor
Warning Be sure to wait for 10 minutes or more after turning off all power supplies before
disassembling work.
Be careful not to get yourself burnt with the pipes and other parts that are heated by
the gas brazing machine.
If the refrigerant gas leaks during work, ventilate the room. (If the refrigerant gas is
exposed to flames, toxic gas may be generated.)
Caution From the viewpoint of global environment protection, do not discharge the refrigerant
gas in the atmosphere. Make sure to collect all the refrigerant gas.
Restore the piping by non-oxidation brazing.
Note Before working, make sure that the refrigerant gas is empty in the circuit.
Be sure to apply nitrogen replacement when heating up the brazed part.
Do not use a metal saw for cutting pipes by all means because the sawdust comes into
the circuit.
When withdrawing the pipes, be careful not to pinch them firmly with pliers. The pipes
may get deformed.
Provide a protective sheet or a steel plate so that the brazing flame cannot influence
peripheries.
Be careful so as not to burn the compressor terminals, the name plate, the outdoor
heat exchanger fin.
In case of difficulty with gas brazing machine
1. Disconnect the brazed part where is easy to disconnect and restore.
2. Cut pipes on the main unit with a tube cutter in order to make it easy to disconnect.
Step Procedure Points
1Remove the putty.
2Heat up and disconnect
the brazed parts to
remove the distributor.
(R5595)
Putty
Distributor
Brazed
parts
(R17263)