Midea MSMBB-12CRDN1-MP0W, MSMBC-18CRDN1-MP0W, MSMBD-22CRDN1-MP5W Service Manual

Revision A: 1502250001, Content updated.

National Electrical Code NFPA70/ANSI C1-1993 or current edition and Canadian Electrical
Code Part1 CSA C.22.1.

• The information contained in the manual is intended for use by a qualified service technician
familiar with safety procedures and equipped with the proper tools and test instruments

• Installation or repairs made by unqualified persons can result in hazards to you and others.

• Failure to carefully read and follow all instructions in this manual can result in equipment

SERVICE MANUAl

DC Inverter Air Conditioner

Table of Contents

1. Precaution

2. Part Names

3. Dimension

4. Refrigerant Cycle Diagram

5. Printed Circuit Board Connector Wiring Diagram of Outdoor Unit

6. Installation Details

7. Operation Characteristics

8. Electronic Function

9. Troubleshooting

10. Disassembly Instructions

Mini Split 3D

MSMBB-12CRDN1-MP0W
MSMBC-18CRDN1-MP0W
MSMBD-22CRDN1-MP5W

WARNING

• Installation MUST conform with local building codes or, in the absence of local codes, with the

malfunction, property damage, personal injury and/or death.

Models:

This Manual Is For Qualified Service Engineer Use Only

1. Precaution

..................................................................................................................................................... 1

1.1 Safety Precaution .......................................................................................................................... 1

1.2 Warning .......................................................................................................................................... 1

2. Part Names

.................................................................................................................................................... 4

2.1 Model Names of Indoor/Outdoor units .......................................................................................... 4

2.2 Part names of Indoor/Outdoor units .............................................................................................. 5

3. Dimension

..................................................................................................................................................... 6

3.1 Indoor Unit ..................................................................................................................................... 6

3.2 Outdoor Unit................................................................................................................................... 8

4. Refrigerant Cycle Diagram

.......................................................................................................................... 9

5. Printed Circuit Board Connector Wiring Diagram of Outdoor unit

....................................................... 10

6 Installation Details

....................................................................................................................................... 12

6.1 Wrench torque sheet for installation ............................................................................................ 12

6.2 Connecting the cables ................................................................................................................. 12

6.3 Pipe length and the elevation ...................................................................................................... 12

6.4 Installation for the first time .......................................................................................................... 13

6.5 Adding the refrigerant after running the system for many years ................................................. 14

6.6 Procedure when servicing the indoor unit refrigeration circuit. .................................................. 14

6.7 Evacuation after servicing the outdoor unit refrigeration circuit. ................................................ 16

7. Operation Characteristics

......................................................................................................................... 18

8. Electronic function

..................................................................................................................................... 19

8.1 Abbreviation ................................................................................................................................. 19

8.2 Display function ........................................................................................................................... 19

8.3 Main Protection ............................................................................................................................ 20

8.4 Operation Modes and Functions ................................................................................................. 21

9. Troubleshooting

......................................................................................................................................... 26

9.1 Indoor Unit Error Display ............................................................................................................. 27

9.2 Outdoor unit error display ............................................................................................................ 28

9.3 Diagnosis and Solution ................................................................................................................ 31

10 Disassembly Instructions

......................................................................................................................... 56

10.1 Indoor unit .................................................................................................................................. 56

10.2 Outdoor unit ............................................................................................................................... 60

Table Of Contents

1

1. Precaution

1.1 Safety Precaution

n To prevent injury to the user or other

people and property damage, the following
instructions must be followed.

n Incorrect operation due to ignoring

instruction will cause harm or damage.

n Before service the unit, be sure to

read this service manual at first.

1.2 Warning

Ø Installation

n Do not use a defective or underrated

circuit breaker. Use this appliance on a
dedicated circuit.

There is risk of fire or electric shock.

n For electrical work, contact the dealer,

seller, a qualified electrician, or an
authorized service center.

Do not disassemble or repair the product,
there is risk of fire or electric shock.

n Always ground the product.

There is risk of fire or electric shock.

n Install the panel and the cover of

control box securely.

There is risk of fire of electric shock.

n Always install a dedicated circuit and

breaker.

Improper wiring or installation may cause
electric shock.

n Use the correctly rated breaker of

fuse.

There is risk of fire or electric shock.

n Do not modify or extend the power

cable.

There is risk of fire or electric shock.

n Do not install, remove, or reinstall the

unit by yourself (customer).

There is risk of fire, electric shock, explosion,
or injury.

n Be caution when unpacking and

installing the product.

Sharp edges could cause injury, be especially
careful of the case edges and the fins on the
condenser and evaporator.

n For installation, always contact the

dealer or an authorized service center.

n Do not install the product on a

defective installation stand.

n Be sure the installation area does not

deteriorate with age.

If the base collapses, the air conditioner could
fall with it, causing property damage, product
failure, and personal injury.

n Do not let the air conditioner run for a

long time when the humidity is very high
and a door or a window is left open.

n Take care to ensure that power cable

could not be pulled out or damaged during
operation.

There is risk of fire or electric shock.

n Do not place anything on the power

cable.

There is risk of fire or electric shock.

n Do not plug or unplug the power

supply plug during operation.

There is risk of fire or electric shock.

n Do not touch (operation) the product

with wet hands.

n Do not place a heater or other

appliance near the power cable.

There is risk of fire and electric shock.

n Do not allow water to run into

electrical parts.

It may cause fire, failure of the product, or
electric shock.

n Do not store or use flammable gas or

combustible near the product.

There is risk of fire or failure of product.

n Do not use the product in a tightly

closed space for a long time.

Oxygen deficiency could occur.

n When flammable gas leaks, turn off

the gas and open a window for ventilation
before turn the product on.

n If strange sounds or smoke comes

from product, turn the breaker off or
disconnect the power supply cable.

2

There is risk of electric shock or fire.

n Stop operation and close the window

in storm or hurricane. If possible, remove
the product from the window before the
hurricane arrives.

There is risk of property damage, failure of
product, or electric shock.

n Do not open the inlet grill of the

product during operation. (Do not touch the
electrostatic filter, if the unit is so equipped.)

There is risk of physical injury, electric shock,
or product failure.

n When the product is soaked, contact

an authorized service center.

There is risk of fire or electric shock.

n Be caution that water could not enter

the product.

There is risk of fire, electric shock, or product
damage.

n Ventilate the product from time to

time when operating it together with a stove
etc.

There is risk of fire or electric shock.

n Turn the main power off when

cleaning or maintaining the product.

There is risk of electric shock.

n When the product is not be used for a

long time, disconnect the power supply plug
or turn off the breaker.

There is risk of product damage or failure, or
unintended operation.

n Take care to ensure that nobody

could step on or fall onto the outdoor unit.

This could result in personal injury and
product damage.

Ø CAUTION

n Always check for gas (refrigerant)

leakage after installation or repair of
product.

Low refrigerant levels may cause failure of
product.

n Install the drain hose to ensure that

water is drained away properly.

A bad connection may cause water leakage.

n Keep level even when installing the

product.

It can avoid vibration of water leakage.

n Do not install the product where the

noise or hot air from the outdoor unit could
damage the neighborhoods.

It may cause a problem for your neighbors.

n Use two or more people to lift and

transport the product.

n Do not install the product where it will

be exposed to sea wind (salt spray) directly.

It may cause corrosion on the product.
Corrosion, particularly on the condenser and
evaporator fins, could cause product
malfunction or inefficient operation.

Ø Operational

n Do not expose the skin directly to

cool air for long time. (Do not sit in the
draft).

n Do not use the product for special

purposes, such as preserving foods, works
of art etc. It is a consumer air conditioner,
not a precision refrigerant system.

There is risk of damage or loss of property.

n Do not block the inlet or outlet of air

flow.

n Use a soft cloth to clean. Do not use

harsh detergents, solvents, etc.

There is risk of fire, electric shock, or damage
to the plastic parts of the product.

n Do not touch the metal parts of the

product when removing the air filter. They
are very sharp.

n Do not step on or put anything on the

product. (outdoor units)

n Always insert the filter securely.

Clean the filter every two weeks or more
often if necessary.

A dirty filter reduces the efficiency of the air
conditioner and could cause product
malfunction or damage.

n Do not insert hands or other objects

through air inlet or outlet while the product
is operated.

n Do not drink the water drained from

the product.

3

n Use a firm stool or ladder when

cleaning or maintaining the product.

Be careful and avoid personal injury.

n Replace the all batteries in the remote

control with new ones of the same type. Do
not mix old and new batteries or different
types of batteries.

There is risk of fire or explosion.

n Do not recharge or disassemble the

batteries. Do not dispose of batteries in a
fire.

They may burn of explode.

n If the liquid from the batteries gets

onto your skin or clothes, wash it well with
clean water. Do not use the remote of the
batteries have leaked.

4

2. Part Names

2.1 Model Names of Indoor/Outdoor units

Series

Capacity Indoor units

Outdoor units

Inverter

12k MSMBB-12CRDN1-MP0W MOB1-12CDN1-MP0W
18k MSMBC-18CRDN1-MP0W MOC-18CDN1-MP0W
22k MSMBD-22CRDN1-MP5W MOF1-22CDN1-MP5W

5

2.2 Part names of Indoor/Outdoor units

6

3. Dimension

3.1 Indoor Unit

Model W D H

MSMBB-12CRDN1-MP0W

810 mm

(31.89in)

200 mm

(7.87in)

300 mm

(11.81in)

MSMBC-18CRDN1-MP0W

980 mm

(38.58in)

225 mm

(8.86in)

325 mm

(12.80in)

MSMBD-22CRDN1-MP5W

1090 mm

(42.91in)

235 mm

(9.25in)

338 mm

(13.31in)

7

For MSMBB-12CRDN1-MP0W,

For MSMBC-18CRDN1-MP0W,

For MSMBD-22CRDN1-MP5W,

8

3.2 Outdoor Unit

More than 60cm(23.6in)

More than 70cm(27.6in)

More than 30cm(11.8in)

More than 60cm(23.6in)
(Service space)

Fence or

obstacles

More than 30cm(11.8in)

Note: The above drawing is only for reference. The appearance of your units may be different.

Model W D H W1 A B

MOB1-12CDN1-MP0W

780mm
(30.7in)

250mm

(9.8in)

540mm
(21.3in)

843mm
(33.2in)

549mm
(21.6in)

276mm
(10.9in)

MOC-18CDN1-MP0W

760 mm

(29.92in)

285 mm

(11.22in)

590 mm

(23.23in)

823 mm

(32.4in)

530 mm

(50.87in)

290 mm

(11.42in)

MOF1-22CDN1-MP5W

845mm
(33.3in)

320mm
(12.6in)

700mm
(27.6in)

908mm
(35.7in)

560mm
(22.0in)

335mm
(13.2in)

9

4. Refrigerant Cycle Diagram

For cooling only models,

INDOOR

OUTDOOR

LIQUID SIDE

GAS SIDE

HEAT
EXCHANGE
(EVAPORATOR)

HEAT
EXCHANGE
(CONDENSER)

COMPRESSOR

CAPILIARY TUBE

10

5. Printed Circuit Board Connector Wiring Diagram of Outdoor unit

MOB1-12CDN1-MP0W,

U

V

W

T3-TipeT4-OutDoorTP

PFC-1310

202302130949 CE-KFR26W/BP2(MDY02+1243).D.13.WP2-1

[1.4]2014.02.20

HF

LF

IC2

IC6
PC851

IC5PC817

CN27

FAN_C

CN26 FAN_C

BR2

HS3

OCP1

COM1

HIN1

VB1

HS1

FO2

OCP2

FO1

LS1

U

LS2

V

LS3

W

VBB

VCC3

VB3

COM3

LIN3

OCP3

FO3

HS2

VB2

VCC2

HIN2

COM2

LIN2

VCC1

LIN1

HIN3

IPM1

BR1

PTC1

CN2

CN1

CN8

CN7

CN21

+

LED1
Yellow

C6

R33
R16

C23

C7

L1

RY1

D3

D1

E8

R67

R66R61

R57R56

R53

R4

C9

CN19AC_FAN

D4

C28

C18

R77

D5

C54

R65

R64

R5

C52

ZR2

ZR1

RY5

RY4

RY3

RY2

R58

R55R47

R46

R45

R44

R43

R42

R39

R36

R35

R32

R31

R30
R29

R21

R19

R18

R17

R15

R14

R11

R10

R9

R8

R7

R6

R2

Q1

IC7

IC1

FUSE1T20A/250VAC

E17

E21

E15

E12E9

+

+

E6

DSA1

D7

D6

D2

C49

C42

C41

C40

C39

C38

C36

C35

C33

C31

C30

C26

C25

C24

C22

C20

C16

C15

C14

C13

C12

C11

C10

C3

C2

C1

IC8

+

-

~~

SSR1

E1

E4

E5

R59

R12

C27

E2

R78

E3

T1

C29

IC10

CN22

CN14
TestPort

C32 C34

C58

C61

C62

C63

C76

C77

C85

C89

C90

C91

C98

C100

C108

C113

C71C51

C148

CN28E2-Burning

CN29Simulation

D13

D14

E11

E13

E10

IC4-1

L3

R24

R25

R26

R27

R28

R60

R63

R82

R83

R84

R85

R86R87

R88

R89

R90

R92

R94

R96

R97

R99

R101R103

R105

R111

R118

R122

R129 R20

R48

R51

R49

R50

R145

R146

C37

C70

C80

R13

E16

R3

R37

R38

R79

R91

C8

C17

R40

R41

R1

C82 C83

IC9

IC4

D9

R54

CN9

Earth

LED2RED

R23

CN42

CompTop

C21

C19

R34

C5

C45

C46

CN60

CN11

4-WAY-L

CN12

4-WAY-N

CN23

N-IN

CN24

L-IN

CN25

S

CN20

C4

R52

C43

C44

C81

R22

D8

X1

DZ1DZ4

DZ5

DZ2

IC3

C47

C48

DZ3

connect to the terminal

CN24(L-IN)-CN23(N-IN)

208-230V AC

power supply

when 4-way is ON, output 208-230VAC

connect to the 4-WAY

CN12 CN11

when heater is ON, output 208-230VAC

CN60

connect to compressor heater

3-4 0VAC / 208-230VAC (high speed running)

5

4

3

2

1

connect to outdoor AC FAN

CN19

2-4 0VAC / 208-230VAC (low speed Running)

1

2

3

4

5

CN27 CN26

AC FAN-CAPACITOR

208-230VAC

CN20

CN1

connect TO REACTOR
2-10V AC(standby);
30-150V AC(running);

connect to the compressor
0VAC (standby)
10-200VAC (running)

W

V

U

CN22

room temp sensor(3-4) RT
pipe temp sensor(1-2) RT

Exaust temp sensor(5-6) RT

123546

NO USE

CN29

NO USE

CN28

210-300VDC (Running)

CAPACITOR Voltage

290-330VDC (standby)

+-

LED1

CN14

connect to detector

test port

MOC-18CDN1-MP0W

11

MOF1-22CDN1-MP5W

12

6 Installation Details

6.1 Wrench torque sheet for
installation

Outside diameter Torque

Additional tightening

torque

Ф6.35mm 1/4in 1500N.cm(153kgf.cm) 1600N.cm(163kgf.cm)

Ф9.52mm 3/8in 2500N.cm(255kgf.cm) 2600N.cm(265kgf.cm)

Ф12.7mm 1/2in 3500N.cm(357kgf.cm) 3600N.cm(367kgf.cm)

Ф15.9mm 5/8in 4500N.cm(459kgf.cm) 4700N.cm(479kgf.cm)

Ф19mm 3/4in 6500N.cm(663kgf.cm) 6700N.cm(683kgf.cm)

6.2 Connecting the cables

The power cord should be selected according
to the following specifications sheet.

Appliance Amps AWG Wire Size

10 18
13 16
18 14
25 12
30 10

The cable size and the current of the fuse or
switch are determined by the maximum
current indicated on the nameplate which
located on the side panel of the unit. Please
refer to the nameplate before selecting the
cable, fuse and switch.

6.3 Pipe length and the elevation

Models

Pipe size

Gas Liquid

MSMBB-12CRDN1-MP0W+MOB1-12CDN1-M P0W

3/8in

(Ф9.52mm)

1/4in

(Ф6.35mm)

MSMBC-18CRDN1-MP0W+MOC-18CDN1-M P0W

1/2in

(Ф12.7mm)

1/4in

(Ф6.35mm)

MSMBD-22CRDN1-MP5W+MOF1-22CDN1-

M P5W

5/8in

(Ф15.9mm)

3/8in

(Ф9.52mm)

Models

Standa

rd

length

Max.

Elevation

Max.

Length

A

Additional

refrigerant

MSMBB-12CRDN1-MP0W+
MOB1-12CDN1-M P0W

7.5m

(24.6ft)

10m

(32.8ft)

25m

(82.0ft)

15g/m

(0.16oz/ft)

MSMBC-18CRDN1-MP0W+
MOC-18CDN1-M P0W

7.5m

(24.6ft)

20m

(65.6ft)

30m

(98.4ft)

15g/m

(0.16oz/ft)

MSMBD-22CRDN1-MP5
W+MOF1-22CDN1-M
P5W

7.5m

(24.6ft)

20m

(65.6ft)

30m

(98.4ft)

30g/m

(0.32oz/ft)

13

6.4 Installation for the first time

Air and moisture in the refrigerant system have
undesirable effects as below:

● Pressure in the system rises.

● Operating current rises.

● Cooling or heating efficiency drops.

● Moisture in the refrigerant circuit may

freeze and block capillary tubing.

● Water when mixed with the refrigerant and oil

will create an acid that will damage the motor
windings and components in the refrigerant

system.

Therefore, the indoor units and the pipes
between indoor and outdoor units must be leak
tested and evacuated to remove gas and
moisture from the system.

Gas leak check (Soap water method):

Apply soap water or a liquid neutral
detergent on the indoor unit connections or
outdoor unit Connections with a soft brush to
check for leakage of the connecting points of
the piping. If bubbles come out, the pipes have
leakage.

1. Air purging with vacuum pump

1) Completely tighten the flare nuts of the

indoor and outdoor units, confirm that both
the 2-way and 3-way valves are set to the

Front seated.

2) Connect the low pressure gauge to the 3 way

service valve access port..

3) Connect the middle hose of the gauge

manifold (usually yellow) to the vacuum
pump.

4) Fully open the handle for the low pressure

gauge..

5) Start the vacuum pump and operate according

to manufacture spec's.

6) Perform an evacuation for a minimum of 30
minutes and check that the low pressure
(compound) gauge indicates a vacuum of 29.9
in/hg (500 microns) A vacuum gauge should
be used if available. If the proper vacuum
cannot be achieved the vacuum pump should
be run for an additional 20 minutes. If after the
additional 20 minutes the vacuum still cannot
be achieved the is a leak in the system and
must be located and repaired. follow the leak
checking procedure as mentioned before. If
the vacuum is achieved, close the low pressure
gauge handle off and shut the vacuum pump
off. Recheck the reading after 10 minutes, the
vacuum may change slightly, this is normal.

7) The system is now dry and free of

contaminates, refrigerant pressure should
now be added to the system from a source
other than the system before opening the 2
way and 3 way valves for system operation.

8) The 2 way and 3 way valve can now be

opened for the system operation

2. Air purging by refrigerant

Procedure:

1). Confirm that both the 2-way and 3-way

valves are set to the closed position.

2). With a container of refrigerant and a gauge

manifold set, connect the low pressure gauge hose

14

to the 3 way valve service port and a charging

cylinder to the service port of the 3-way valve.

3). Open the valve on the refrigerant container and

the low pressure gauge to allow the refrigerant to
enter the system, next loosen the flare connection
on the 2 way valve line to purge the air and
contaminants from the system for 30 to 50
seconds, then retighten the connection.

4). Next allow the pressure from the refrigerant to

reach 100 psi and then close the low pressure
gauge and the refrigerant container and check the
2 way and 3 way valve line connections for leaks
with liquid soap or electronic leak detector.

5). After the system has been check for leaks the

pressure should be adjusted to about 25 to 50 psi.

6). You can now disconnect the gauge manifold

and refrigerant container from the system and
open the 2 way and 3 way valves for system
operation

7). Mount the valve stems nuts and the service
port cap.
Be sure to use a torque wrench to tighten the
service port cap to a torque 18N·m(13.27 ft.lbs).
Be sure to check the gas leakage.

6.5 Adding the refrigerant after running
the system for many years

Procedure

1). 1st step; Connect the low pressure gauge from

the gauge manifold set to the 3 way service valve
(this is the blue hose on most sets) 2nd step;
Connect the middle hose from the manifold set to
the refrigerant container (this is the yellow line on
most sets). with refrigerant 410A the container
must be inverted (upside down) when adding the
refrigerant. Note that the 2 way and 3 way valves

must be in the open position.
3rd step; the air in the gauge hoses needs to be
purged out. use the pressure from the system to
purge the low side line, loosen the connection on
the manifold for a second, next open the to valve
on the refrigerant container to pressurize the line,
now loosen that hose at the manifold for a second
and purge that line.

3) Next step is to set the refrigerant container on

an electronic charging scale and record the weight
or zero the scale depending on the scale used.
Next determine the refrigerant charge to be
added.

4) Start the unit in the cooling mode and lower the

set point so the unit wont shut off during the
charging procedure.

5) Refrigerant can now be added to the system,

open the low pressure valve on the gauge manifold
set to start charging the unit with liquid refrigerant,
keep track of the refrigerant being added to the
system (do not overcharge the system)

6). Once the correct charge has been added to the

system close the low pressure valve on the gauge
manifold set and record the operating pressure.
The system is now charged and the unit can be
shut off. Close the valve on the refrigerant
container and disconnect the hose from the
manifold set, also disconnect the hose from the 3
way valve and replace and torque all caps.

7). Mount the valve stem caps and the service

port
Use torque wrench to tighten the service port
cap to a torque of 18N.m(13.27 ft,lbs).

Always leak check after servicing the refrigerant
system.

6.6 Procedure when servicing the indoor

unit refrigeration circuit.

1. Pumping down the system (isolating the

refrigerant charge in the condensing unit)

15

Procedure

1). With the unit in the cooling mode and a low set

point remove all caps from the 3 way and 2 way
valves, next attach the low pressure gauge to the 3
way service valve port and purge the air from that
hose by loosening the hose at the manifold for a
second, be sure the low pressure gauge valve is
closed. be sure to record the operating
pressure, you will need to know this when you
complete the service on the indoor unit and restart
the system. Now prepare to close both valves on
the unit starting with the 2 way valve (this is called
front seating the valve) also prepare to shut the
power off to the outdoor unit.

2). Connect the charge hose with the push pin
of handle lo to the 3-way valves gas service
port.

3). Air purging of the charge hose.
Open the handle Lo valve of the manifold valve
slightly to purge air from the charge hose for 5
seconds and then close it quickly.

4). Now close the 2 way valve and monitor the low

pressure gauge. the pressure will start to drop.

5). Operate the unit in the cooling mode and

disconnect the power to the outdoor unit when the
low side gauge reads a slight vacuum, running the
compressor in a vacuum could damage the motor
windings. Note that units with extended lines and
additional refrigerant charge may not be able to
achieve a vacuum, this is because the outdoor
unit can only store a certain amount of refrigerant,
this is normal (the amperage of the compressor
will have to be monitored in this case) Stop
compressor when the amperage approaches the
name plate FLA rating indicates 0.1Mpa(14.5Psi).

6). Now close the 3 way valve right away. the

pressure will rise during this time, this is normal.
There will be some pressure left in the system this
is normal, The indoor unit is now ready to be
serviced.

Disconnect the charge set, and tighten the
2-way and 3-way valve’s stem nuts.
Use a torque wrench to tighten the 3-way valves
service port cap to a torque of 18N.m(= 13.27

ft.lbs).

Be sure to check for gas leakage.

2. Sweeping (air purging) the system with

refrigerant after the service to the
refrigerant circuit of the indoor unit is
complete.

Procedure:

Sweeping the system can be used when the unit
has been pumped down, this eliminates the need
to loosen the flare connection on the 2 way valve
(loosening and retightening flare connections
could cause a refrigerant leak)

1). Confirm that both the 2-way and 3-way

valves are set to the closed position.

2). Connect the charge set and a charging

cylinder to the service port of the 3-way valve
Leave the valve on the Refrigerant container.

3). Do not loosen the flare connection, Start with

the hose from the low pressure gauge that has
been connected to the 3 way valve service port
and loosen it at the gauge manifold connection,
next open the 2 way valve 1/2 half of a turn (this
will release the refrigerant that has been isolated in
the outdoor unit) The refrigerant will travel thru
the small refrigerant line and evaporator coil in the
indoor unit and back out the low pressure hose
that has been loosened let the refrigerant sweep
for about 50 seconds, this will push and remove

16

any air moisture and noncodensables from the
refrigeration circuit. After 50 seconds has passed
tighten the hose on the low pressure gauge. The
sweep is now complete.
Next step, open the 2 way valve all the way then
the 3 way valve all the way and check for leaks.

4). Next step, Start the unit in the cooling mode

and check the pressure (remember the pressure
you recorded?) The unit is going to be low on
refrigerant from the sweeping process, add
refrigerant as needed from the refrigerant
container in the liquid state to achieve the
operating pressure that you recorded. The process
is now complete.

Check the flare connections for gas leakage.

5). Discharge the refrigerant.
Close the valve on the charging cylinder and
discharge the refrigerant by loosening the flare
nut on the 2-way valve approximately 45’ until
the gauge indicates 0.3Mpa(43.5Psi) to 0.5

Mpa(72.5Psi).

6). Disconnect the charge set and the charging
cylinder, and set the 2-way and 3-way valves to
the open position
Be sure to use a hexagonal wrench to operate
the valve stems.

7). Mount the valve stems nuts and the service
port cap
Be sure to use a torque wrench to tighten the
service port cap to a torque 18N.m.
Be sure to check the gas leakage.

6.7 Evacuation after servicing the outdoor

unit refrigeration circuit.

1. Evacuation of the complete refrigeration

circuit, Indoor and outdoor unit.

Procedure:

1). Confirm that both the 2-way and 3-way

valves are set to the opened position.

2). Connect the vacuum pump to 3-way valve’s

service port.

3). Evacuation for approximately one hour.

Confirm that the compound meter indicates

-0.1Mpa(14.5Psi), 500 Microns / 29.9 in,hg.

4). Close the valve (Low side) on the charge set,

turn off the vacuum pump, and confirm that the
gauge needle does not move (approximately 5
minutes after turning off the vacuum pump).

5). Disconnect the charge hose from the

vacuum pump.

2. Refrigerant charging

Procedure:

1). Connect the charge hose to the charging

cylinder, open the 2-way valve and the 3-way
valve
Connect the charge hose which you
disconnected from the vacuum pump to the
valve at the bottom of the cylinder. If the
refrigerant is R410A, make the cylinder bottom
up to ensure liquid charge.

2). Purge the air from the charge hose

Open the valve at the bottom of the cylinder
and press the check valve on the charge set to
purge the air (be careful of the liquid
refrigerant).

3) Put the charging cylinder onto the electronic

scale and record the weight.

4). Open the valves (Low side) on the charge

set and charge the system with liquid refrigerant
If the system cannot be charge with the
specified amount of refrigerant, or can be

17

charged with a little at a time (approximately
150g each time) , operating the air conditioner
in the cooling cycle; however, one time is not
sufficient, wait approximately 1 minute and then
repeat the procedure.

5).When the electronic scale displays the
proper weight, disconnect the charge hose from
the 3-way valve’s service port immediately
If the system has been charged with liquid
refrigerant while operating the air conditioner,
turn off the air conditioner before disconnecting
the hose.

6). Mounted the valve stem caps and the
service port. Use torque wrench to tighten the
service port cap to a torque of 18N.m. Be sure
to check for gas leakage.

18

7. Operation Characteristics

Temperature

Mode

Cooling operation Heating operation Drying operation

Room temperature

17℃～32℃

(62℉～90℉)

0℃～30℃

(32℉～86℉)

10℃～32℃

(50℉～90℉)

Outdoor temperature

0°C～50°C

(32°F～122°F)

-15°C～30°C
(5°F～86°F)

0°C～50°C

(32°F～122°F)

-15°C～50°C

(5°F～122°F)

(For the models with

low temperature cooling system)

!"(#)

$

+32

CAUTION:

1. If the air conditioner is used beyond the above conditions, certain safety protection features may

come into operation and cause the unit to operate abnormally.

2. The room relative humidity should be less than 80%. If the air conditioner operates beyond this
figure, the surface of the air conditioner may attract condensation. Please set the vertical air flow louver to
its maximum angle (vertically to the floor), and set HIGH fan mode.

3. The optimum performance will be achieved during this operating temperature zone.

19

8. Electronic function

8.1 Abbreviation

T1: Indoor room temperature
T2: Coil temperature of evaporator
T3: Coil temperature of condenser
T4: Outdoor ambient temperature
T5: Compressor discharge temperature

8.2 Display function

8.2.1 Icon explanation on indoor display board.

Digital display:
Displays the temperature settings when the air
conditioner is operational.
Displays the room temperature in FAN mode.
Displays the self-diagnostic codes.

Dispalys ‘ ’ for three seconds when Timer
ON, Fresh, Swing, Turbo or Silence feature is
activated.

Dispalys ‘ ’ for three seconds when Timer
OFF is set.

Dispalys ‘ ’ for three seconds when Fresh,
Swing, Turbo or Silence feature is cancelled.

Dispalys ‘ ’ under deforsting operation.

Dispalys ‘ ’ when anti-cold air feature is
activated under heating mode.

Dispalys ‘ ’ during self clean operation (if
aplicable).

Dispalys ‘ ’ under 8℃ heating operation (if
aplicable).
When ECO function(optional) is actived,the

“ ” illuminates gradually one by one as

In one second interval.

WIFI control display(optional)
Displays when the WIFI control feature is
acticated.(Not available when the unit does not
have this function)

NOTE:
A guide on using the infrared remotr is included
in this literature package.

20

8.3 Main Protection

8.3.1 Three minutes delay at restart for
compressor

Less than 1 minute delay for the 1st time
stand-up and 3 minutes delay for others.

8.3.2 Temperature protection of compressor
top

The unit will stop working when the compressor
top temp. protector cut off, and will restart after
the compressor top temp. protector restart.

8.3.3 Temperature protection of compressor
discharge

Compressor discharge temp. T5>115℃(239°F)
for 5s, compressor stops.

8.3.4 Fan speed is out of control

When Indoor fan speed keeps too low
(300RPM) for certain time, the unit will stop and
the LED will display the failure

8.3.5 Inverter module protection

The Inverter module has a protection function
about current, voltage and temperature. If these
protections happen, the corresponding code
will display on indoor unit and the unit will stop
working.

8.3.6 Indoor fan delayed open function

When the unit starts up, the louver will be active
immediately and the indoor fan will open 10s
later.
If the unit runs in heating mode, the indoor fan
will be also controlled by anti-cold wind

function.

8.3.7 Compressor preheating functions

Preheating permitting condition:
When T4(outdoor ambient temperature)＜
3°C(37.4°F), the preheating function will be
activated.

8.3.8 Sensor protection at open circuit and
breaking disconnection.

When there’s only one temperature sensor in
malfunction , the air conditioner will keep
working but show the error code, in case of any
emergency use.
When there’s more than one temperature
sensor in malfunction, the air conditioner will
stop working

8.3.9 Zero crossing detection error
protection

If AC detects time interval is not correct, the unit
will stop and the LED will display the failure.

8.3.10 Refrigerant leakage detection

This function is only active in cooling mode. It
can better prevent the compressor being
damaged by refrigerant leakage or compressor
overload.
Open condition:
When compressor is active, the value of the
Coil temperature of evaporator T2 has no
change or very little change.

21

8.4 Operation Modes and Functions

8.4.1 Fan mode

(1) Outdoor fan and compressor stop.
(2) Temperature setting function is disabled,
and no setting temperature is displayed.
(3) Indoor fan can be set to high/med/low/auto.
(4) The louver operates same as in cooling
mode.
(5) Auto fan:

a

b

c

d

T1

e

8.4.2 Cooling Mode

8.4.2.1 Compressor running rules

When T1-Ts<-2℃(28.4°F), the compressor will
stop,
when T1—TS>-0.5℃(31.1°F),，the compressor
will be activated.
When the AC run in mute mode, the
compressor will run with low frequency.
When the current is more than setting value,
the current protection function will be activated,
and the compressor will stop.

8.4.2.1 Outdoor fan running rules

The outdoor unit will be run at different fan
speed according to T4.
For different outdoor units,the fan speeds are
different

T4

A+

A

B

C

D
E

8.4.2.2 Indoor fan running rules

In cooling mode, indoor fan runs all the time
and the speed can be selected as high,
medium, low and auto.
When the setting temp. is reached,if the
compressor stop running,indoor fan motor will
run in Minimum speed or setting speed.
The indoor fan is controlled as below:

Setting fan

speed

Actual fan speed

H+(H+=H+G)
A H（=H）
B
C

M+(M+=M+Z)
D M(M=M)
E
F

L+(L+=L+D)
G L(L=L)
H
I

T1-Td ℃(°F)

L

L-(L-=L-D)

H

H-（H-=H-G)

M

M-(M-=M-Z)

The auto fan acts as below rules:

a

b

c

d

T1

e

8.4.2.3 Condenser temperature protection

T3

Resume

Off

Decrease

Hold

When condenser temperature temp. is more
than setting value, the compressor will stop.

8.4.2.5 Evaporator temperature protection

When Evaporator temperature temp.is less
than setting value, the compressor will stop

22

8.4.4 Auto-mode

This mode can be chosen with remote
controller and the setting temperature can be
changed between 17°C(62.6°F)~30°C(86°F).
In auto mode, the machine will choose cooling,
heating or fan-only mode according to ΔT
(ΔT =T1-Ts).

T1-Ts

Cooling

Heating*

Fan only

Heating*: For cooling only models, they will run
at fan speed
Indoor fan will run at auto fan of the relevant
mode.
The louver operates same as in relevant mode.
If the machine switches mode between heating
and cooling, the compressor will keep stopping
for certain time and then choose mode
according to T1-Ts.
If the setting temperature is modified, the
machine will choose running function again.

8.4.5 Drying mode

8.4.5.1 Indoor fan speed is fixed at breeze and
can’t be changed. The louver angle is the same
as in cooling mode.

8.4.5.3 Low indoor room temperature protection
In drying mode, if room temperature is lower
than 10°C(50°F), the compressor will stop and
not resume until room temperature exceeds
12°C(53.6°F).

8.4.5.4 Evaporator anti-freezing protection,
condenser high temperature protection and
outdoor unit frequency limit are active and the
same as that in cooling mode.

8.4.5.5 The outdoor fan operates the same as
in cooling mode.

8.4.6 Forced operation function

8.4.6.1 Enter forced operation function:
When the machine is off, pressing the touch
button will carry the machine to forced auto
mode. If pressing the button once again within
5 seconds, the machine will turn into forced
cooling mode.
In forced auto, forced cooling or any other
operation mode, pressing touch button will turn
off the machine.

8.4.6.2 In forced operation mode, all general
protections and remote control are available.

8.4.6.3 Operation rules:
Forced cooling mode:
The compressor runs at F2 frequency and
indoor fan runs as breeze. After running for 30
minutes. the machine will turn to auto mode as
24°C(75.2°F) setting temperature.
Forced auto mode:
The action of forced auto mode is the same as
normal auto mode with 24°C(75.2°F) setting
temperature.

8.4.7 Auto-Restart function

The indoor unit is equipped with auto-restart
function, which is carried out through an
auto-restart module. In case of a sudden power
failure, the module memorizes the setting
conditions before the power failure. The unit will
resume the previous operation setting (not
including swing function) automatically after 3
minutes when power returns.
If the memorization condition is forced cooling
mode, the unit will run in cooling mode for 30
minutes and turn to auto mode as 24°C(75.2°F)
setting temp.
If AC is off before power off and AC is required
to start up now, the compressor will have 1
minute delay when power on. Other conditions,
the compressor will have 3 minutes delay when
restarts.

23

24

7.4.10 Point check function

Press the LED DISPLAY or LED or MUTE button of the remote controller three times, and then press
the AIR DIRECTION or SWING button three times in ten seconds, the buzzer will keep ring for two
seconds. The air conditioner will enter into the information enquiry status. You can press the LED
DISPLAY or AIR DIRECTION button to check the next or front item’s information.
When the AC enter the “information enquiry” status, it will display the code name in 2 seconds, the

details are as follows.
Enquiry information Displaying code Meaning

T1 T1 T1 temp.
T2 T2 T2 temp.
T3 T3 T3 temp.
T4 T4 T4 temp.
T2B Tb T2B temp.
TP TP TP temp.
TH TH TH temp.
Targeted Frequency FT Targeted Frequency
Actual Frequency Fr Actual Frequency
Indoor fan speed IF Indoor fan speed
Outdoor fan speed OF Outdoor fan speed
EXV opening angle LA EXV opening angle
Compressor continuous running time CT Compressor continuous

running time

Causes of compressor stop. ST Causes of compressor

stop.
Reserve A0
Reserve A1
Reserve 0
Reserve 1
Reserve 2
Reserve 3
Reserve 4
Reserve 5
Reserve 6
Reserve L
Reserve A
Reserve U
Reserve T

When the AC enter into the information enquiry status, it will display the code value in the next 25s, the

details are as follows.

25

Enquiry
information

Display value Meaning Remark

T1,T2,T3,T4,
T2B,TP,TH,
Targeted
Frequency,
Actual
Frequency

-1F,-1E,-1d,-1c,­1b,-1A

-25,-24,-23,-22,-21,-20 1. All the displaying temperature is actual
value.

2. All the temperature is °C no matter what
kind of remote controller is used.

3. T1,T2,T3,T4,T2B display range:-25~70,
TP display range:-20~130.

4. Frequency display range: 0~159HZ.

5. If the actual value exceeds the range, it

will display the maximum value or minimum

value.

-19—99 -19—99
A0,A1,…A9 100,101,…109
b0,b1,…b9 110,111,…119
c0,c1,…c9 120,121,…129
d0,d1,…d9 130,131,…139
E0,E1,…E9 140,141,…149
F0,F1,…F9 150,151,…159

Indoor fan
speed
/Outdoor fan
speed

0 OFF
1,2,3,4 Low speed, Medium

speed, High speed,
Turbo

For some big capacity motors.

14-FF Actual fan

speed=Display value
turns to decimal
value and then
multiply 10. The unit
is RPM.

For some small capacity motors,
display value is from 14-FF(hexadecimal),
the corresponding fan speed range is from
200-2550RPM.

EXV opening
angle

0-FF Actual EXV opening

value=Display value
turns to decimal
value and then

multiply 2.
Compressor
continuous
running time

0-FF 0-255 minutes If the actual value exceeds the

range, it will display the maximum

value or minimum value.
Causes of
compressor
stop.

0-99 For the detailed

meaning, please
consult with engineer

Decimal display

Reserve 0-FF

26

9. Troubleshooting

Safety

Electricity power is still kept in capacitors even the power supply is shut off. Do not forget to discharge the electricity
power in capacitor.

Electrolytic Capacitors

(HIGH VOLTAGE! CAUTION!)

For other models, please connect discharge resistance (approx.100Ω 40W) or soldering iron (plug) between +, ­terminals of the electrolytic capacitor on the contrary side of the outdoor PCB.

Note: The picture above is only for reference. The plug of your side may be different.

27

9.1 Indoor Unit Error Display

Operation

lamp

Timer lamp Display LED STATUS

☆ 1 time

X E0 Indoor unit EEPROM parameter error

☆ 2 times

X E1 Indoor / outdoor units communication error

☆ 3 times

X E2 Zero-crossing signal detection error

☆ 4 times

X E3 Indoor fan speed has been out of control

☆ 5 times

X E4

Indoor room temperature sensor T1 open circuit or short
circuit

☆ 6 times

X E5

Evaporator coil temperature sensor T2 open circuit or
short circuit

☆ 7 times

X EC Refrigerant leakage detection

☆ 1 times

O F0 Overload current protection

☆ 2 times

O F1

Outdoor ambient temperature sensor T4 open circuit or
short circuit

☆ 3 times

O F2

Condenser coil temperature sensor T3 open circuit or
short circuit

☆ 4 times

O F3

Compressor discharge temperature sensor T5 open
circuit or short circuit

☆ 5 times

O F4 Outdoor unit EEPROM parameter error

☆ 6 times

O F5 Outdoor fan speed has been out of control

☆ 1 times ☆

P0 IPM malfunction or IGBT over-strong current protection

☆ 2 times ☆

P1 Over voltage or over low voltage protection

☆ 3 times ☆

P2

High temperature protection of compressor top
diagnosis and solution

☆ 5 times ☆

P4 Inverter compressor drive error

O（light） X（off） ☆（flash）

28

9.2 Outdoor unit error display

MOB1-12CDN1-MP0W,

C24

C22

C20

C16

C15

C14

C13

C12

C11

C10

C3

C2

C1

IC8

+

-

~~

SSR1

E1

E4

E5

R59

R12

C27

E2

R78

E3

T1

C29

IC10

CN22

CN14
TestPort

C32 C34

C58

C61

C62

C63

C76

C77

C85

C89

C90

C91

C98

C100

C108

C113

C71C51

C148

CN28E2-Burning

CN29Simulation

D13

D14

E11

E13

E10

IC4-1

L3

R24

R25

R26

R27

R28

R60

R63

R82

R83

R84

R85

R86

R87

R88

R89

R90

R92

R94

R96

R97

R99

R101

R103

R105

R111

R118

R122

R129 R20

R48

R51

R49

R50

R145

R146

C37

C70

C80

R13

E16

R3

R37

R38

R79

R91

C8

C17

R40

R41

R1

C82 C83

IC9

IC4

D9

R54

CN9

Earth

LED2RED

U

V

W

T3-TipeT4-OutDoorTP

PFC-1310

202302130949 CE-KFR26W/BP2(MDY02+1243).D.13.WP2-1

[1.4]2014.02.20

HF

LF

IC2

IC6

PC851

IC5PC817

CN27

FAN_C

CN26 FAN_C

BR2

HS3

OCP1

COM1

HIN1

VB1

HS1

FO2

OCP2

FO1

LS1

U

LS2

V

LS3

W

VBB

VCC3

VB3

COM3

LIN3

OCP3

FO3

HS2

VB2

VCC2

HIN2

COM2

LIN2

VCC1

LIN1

HIN3

IPM1

BR1

PTC1

CN2

CN1

CN8

CN7

CN21

+

LED1
Yellow

C6

R33
R16

C23

C7

L1

RY1

D3

D1

E8

R67

R66R61

R57

R56

R53

R4

C9

CN19AC_FAN

D4

C28

C18

R77

D5

C54

R65

R64

R5

C52

ZR2

ZR1

RY5

RY4

RY3

RY2

R58

R55

R47

R46

R45

R44

R43

R42

R39

R36

R35

R32

R31

R30
R29

R21

R19

R18

R17

R15

R14

R11

R10

R9

R8

R7

R6

R2

Q1

IC7

IC1

FUSE1 T20A/250VAC

E17

E21

E15

E12E9

++

E6

DSA1

D7

D6

D2

C49

C42

C41

C40

C39

C38

C36

C35

C33

C31

C30

C26

C25

R23

CN42

CompTop

C21

C19

R34

C5

C45

C46

CN60

CN11

4-WAY-L

CN12

4-WAY-N

CN23

N-IN

CN24

L-IN

CN25

S

CN20

C4

R52

C43

C44

C81

R22

D8

X1

DZ1DZ4

DZ5

DZ2

IC3

C47

C48

DZ3

1

2

3

4

5

1235 46

LED1-Yellow

status light, by which you can judge the unit Normal or Error

(standby) Flashing once per second(low speed flashing)
(error) Flashing once per half second (high speed flashing)

(running) aways on

29

MOC-18CDN1-MP0W

No. Problems

LED2
(Green)

LED1
(Red)

IU display

1 standby for normal O X
2 Operation normally X O
3 IPM malfunction or IGBT over-strong current protection

☆

X P0
4 Over voltage or too low voltage protection O O P1
5 Over voltage or too low voltage protection O

☆

P1

6 Inverter compressor drive error X

☆

P4

7 Inverter compressor drive error

☆

O P4
8 Inverter compressor drive error

☆ ☆

P4

30

MOF1-22CDN1-MP5W

31

9.3 Diagnosis and Solution

9.3.1 EEPROM parameter error diagnosis and solution(E0/F4)

Error Code

E0/F4

Malfunction decision
conditions

Indoor or outdoor PCB main chip does not receive feedback
from EEPROM chip.

Supposed causes ● Installation mistake

● PCB faulty

Trouble shooting:

Yes

Replace the indoor/outdoor

main PCB.

Power off, then restart the

unit 2 minuteslater.

EEPROM: a read-only memory whose contents can be erased and reprogrammed using a pulsed
voltage. For the location of EEPROM chip, please refer to the below photos.

Indoor PCB

Outdoor PCB(18k model)

Note: The two photos above are only for reference, it’s may be not same totally with the ones on

your

side.

32

9.3.2 Indoor / outdoor unit’s communication diagnosis and solution(E1)

Error Code

E1

Malfunction decision
conditions

Indoor unit does not receive the feedback from outdoor unit during

110 seconds and this condition happens four times continuously.

Supposed causes ● Wiring mistake

● Indoor or outdoor PCB faulty

Trouble shooting:

33

Remark:

Use a multimeter to test the DC voltage
between L2 port and S port of outdoor
unit. The red pin of multimeter connects
with L2 port while the black pin is for S
port.

When AC is normal running, the voltage
will move alternately between -50V to
50V.

If the outdoor unit has malfunction, the
voltage will move alternately with positive
value.

While if the indoor unit has malfunction,
the voltage will be a certain value.

Remark:

Use a multimeter to test the resistance
of the reactor which does not connect
with capacitor.
The normal value should be around zero
ohm. Otherwise, the reactor must have
malfunction and need to be replaced.

34

9.2.3 Zero crossing detection error diagnosis and solution（E2）

35

9.3.4 Fan speed has been out of control diagnosis and solution(E3)

Error Code

E3/F5

Malfunction decision
conditions

When indoor fan speed keeps too low (300RPM) for certain time,
the unit will stop and the LED will display the failure.

Supposed causes ● Wiring mistake

● Fan ass’y faulty

● Fan motor faulty

● PCB faulty

Trouble shooting:

36

Index 1:
1:Indoor or Outdoor DC Fan Motor(control chip is in fan motor)

Power on and when the unit is in standby, measure the voltage of pin1-pin3, pin4-pin3 in fan motor
connector. If the value of the voltage is not in the range showing in below table, the PCB must has
problems and need to be replaced.

DC motor voltage input and output(voltage: 220-240V~)

NO. Color Signal

Voltage

1 Red Vs/Vm

280V~380V
2 --- --- --­3 Black GND 0V
4 White Vcc 14-17.5V
5 Yellow Vsp 0~5.6V
6 Blue FG 14-17.5V

DC motor voltage input and output(voltage :115V~)

NO. Color Signal

Voltage

1 Red Vs/Vm

140V~190V
2 --- --- --­3 Black GND 0V
4 White Vcc 14-17.5V
5 Yellow Vsp 0~5.6V
6 Blue FG 14-17.5V

2. Outdoor DC Fan Motor (control chip is in outdoor PCB)
Power on ,and check if the fan can run normally, if the fan can run normally, the PCB must has
problems and need to be replaced, If the fan can’t run normally, measure the resistance of each two
pins. If the resistance is not equal to each other, the fan motor must have problems and need to be
replaced, otherwise the PCB must has problems and need to be replaced.

3. Indoor AC Fan Motor
Power on and set the unit running in fan mode at high fan speed. After running for 15 seconds,
measure the voltage of pin1 and pin2. If the value of the voltage is less than 100V(208~240V power

37

supply)or 50V(115V power supply), the PCB must has problems and need to be replaced.

38

9.3.5 Open circuit or short circuit of temperature sensor diagnosis and solution(E5)

Error Code

E4/E5/F1/F2/F3

Malfunction decision
conditions

If the sampling voltage is lower than 0.06V or higher than 4.94V,
the LED will display the failure.

Supposed causes ● Wiring mistake

● Sensor faulty

Trouble shooting:

39

9.3.6 Refrigerant Leakage Detection diagnosis and solution(EC)

Error Code

EC

Malfunction decision
conditions

Define the evaporator coil temp.T2 of the compressor just starts
running as Tcool.
In the beginning 5 minutes after the compressor starts up, if T2
＜Tcool－2°C(Tcool－35.6°F) does not keep continuous 4
seconds and this situation happens 3 times, the display area will
show “EC” and AC will turn off.

Supposed causes ● T2 sensor faulty

● Indoor PCB faulty

● System problems, such as leakage or blocking.

Trouble shooting:

40

9.3.7 Overload current protection diagnosis and solution(F0)

Error Code

F0

Malfunction decision
conditions

An abnormal current rise is detected by checking the specified
current detection circuit.

Supposed causes ● Power supply problems.

● System blockage

● PCB faulty

● Wiring mistake

● Compressor malfunction

41

9.3.8 IPM malfunction or IGBT over-strong current protection diagnosis and solution(P0)

Error Code

P0

Malfunction decision
conditions

When the voltage signal that IPM send to compressor drive chip
is abnormal, the display LED will show “P0” and AC will turn off.

Supposed causes ● Wiring mistake

● IPM malfunction

● Outdoor fan ass’y faulty

● Compressor malfunction

● Outdoor PCB faulty

Trouble shooting:

42

For example:

P-U

P-V

Note: The photos below are only for reference, it’s may be not same totally with the ones on your

side.

43

P-W

N-U

44

N-V

N-W

45

9.3.9 Over voltage or too low voltage protection diagnosis and solution(P1)

Error Code

P1

Malfunction decision
conditions

An abnormal voltage rise or drop is detected by checking the
specified voltage detection circuit.

Supposed causes ● Power supply problems.

● System leakage or block

● PCB faulty

Trouble shooting:

Remark:

Measure the DC voltage
between P and N port. The
normal value should be
around 310V.

P

N

46

9.3.10 High temperature protection of compressor top diagnosis and solution(P2)

Error Code

P2

Malfunction decision
conditions

If the sampling voltage is not 5V, the LED will display the failure.

Supposed causes ● Power supply problems.

● System leakage or block

● PCB faulty

Trouble shooting:

47

9.3.11 Inverter compressor drive error diagnosis and solution(P4)

Error Code

P4

Malfunction decision
conditions

An abnormal inverter compressor drive is detected by a special
detection circuit, including communication signal detection,
voltage detection, compressor rotation speed signal detection
and so on.

Supposed causes ● Wiring mistake

● IPM malfunction

● Outdoor fan ass’y faulty

● Compressor malfunction

● Outdoor PCB faulty

Trouble shooting:

48

Main parts check

1. Temperature sensor checking

Disconnect the temperature sensor from PCB, measure the resistance value with a tester.

Temperature sensors.
Room temp.(T1) sensor,
Indoor coil temp.(T2) sensor,
Outdoor coil temp.(T3) sensor,
Outdoor ambient temp.(T4) sensor,
Compressor discharge temp.(T5) sensor.
Measure the resistance value of each winding by using the multi-meter.

49

Appendix 1 Temperature Sensor Resistance Value Table for T1,T2,T3,T4 (°C--K)

°C °F

K Ohm

°C °F

K Ohm

°C °F

K Ohm

°C °F

K Ohm

-20 -4 115.266 20 68 12.6431 60 140 2.35774 100 212 0.62973

-19 -2 108.146 21 70 12.0561 61 142 2.27249 101 214 0.61148

-18 0 101.517 22 72 11.5 62 144 2.19073 102 216 0.59386

-17 1 96.3423 23 73 10.9731 63 145 2.11241 103 217 0.57683

-16 3 89.5865 24 75 10.4736 64 147 2.03732 104 219 0.56038

-15 5 84.219 25 77 10 65 149 1.96532 105 221 0.54448

-14 7 79.311 26 79 9.55074 66 151 1.89627 106 223 0.52912

-13 9 74.536 27 81 9.12445 67 153 1.83003 107 225 0.51426

-12 10 70.1698 28 82 8.71983 68 154 1.76647 108 226 0.49989

-11 12 66.0898 29 84 8.33566 69 156 1.70547 109 228 0.486

-10 14 62.2756 30 86 7.97078 70 158 1.64691 110 230 0.47256

-9 16 58.7079 31 88 7.62411 71 160 1.59068 111 232 0.45957

-8 18 56.3694 32 90 7.29464 72 162 1.53668 112 234 0.44699

-7 19 52.2438 33 91 6.98142 73 163 1.48481 113 235 0.43482

-6 21 49.3161 34 93 6.68355 74 165 1.43498 114 237 0.42304

-5 23 46.5725 35 95 6.40021 75 167 1.38703 115 239 0.41164

-4 25 44 36 97 6.13059 76 169 1.34105 116 241 0.4006

-3 27 41.5878 37 99 5.87359 77 171 1.29078 117 243 0.38991

-2 28 39.8239 38 100 5.62961 78 172 1.25423 118 244 0.37956

-1 30 37.1988 39 102 5.39689 79 174 1.2133 119 246 0.36954
0 32 35.2024 40 104 5.17519 80 176 1.17393 120 248 0.35982
1 34 33.3269 41 106 4.96392 81 178 1.13604 121 250 0.35042
2 36 31.5635 42 108 4.76253 82 180 1.09958 122 252 0.3413
3 37 29.9058 43 109 4.5705 83 181 1.06448 123 253 0.33246
4 39 28.3459 44 111 4.38736 84 183 1.03069 124 255 0.3239
5 41 26.8778 45 113 4.21263 85 185 0.99815 125 257 0.31559
6 43 25.4954 46 115 4.04589 86 187 0.96681 126 259 0.30754
7 45 24.1932 47 117 3.88673 87 189 0.93662 127 261 0.29974
8 46 22.5662 48 118 3.73476 88 190 0.90753 128 262 0.29216
9 48 21.8094 49 120 3.58962 89 192 0.8795 129 264 0.28482

10 50 20.7184 50 122 3.45097 90 194 0.85248 130 266 0.2777
11 52 19.6891 51 124 3.31847 91 196 0.82643 131 268 0.27078
12 54 18.7177 52 126 3.19183 92 198 0.80132 132 270 0.26408
13 55 17.8005 53 127 3.07075 93 199 0.77709 133 271 0.25757
14 57 16.9341 54 129 2.95896 94 201 0.75373 134 273 0.25125
15 59 16.1156 55 131 2.84421 95 203 0.73119 135 275 0.24512
16 61 15.3418 56 133 2.73823 96 205 0.70944 136 277 0.23916
17 63 14.6181 57 135 2.63682 97 207 0.68844 137 279 0.23338
18 64 13.918 58 136 2.53973 98 208 0.66818 138 280 0.22776
19 66 13.2631 59 138 2.44677 99 210 0.64862 139 282 0.22231

50

Appendix 2 Temperature Sensor Resistance Value Table for T5 (°C --K)

°C °F

K Ohm

°C °F

K Ohm

°C °F

K Ohm

°C °F

K Ohm

-20 -4 542.7 20 68 68.66 60 140 13.59 100 212 3.702

-19 -2 511.9 21 70 65.62 61 142 13.11 101 214 3.595

-18 0 483 22 72 62.73 62 144 12.65 102 216 3.492

-17 1 455.9 23 73 59.98 63 145 12.21 103 217 3.392

-16 3 430.5 24 75 57.37 64 147 11.79 104 219 3.296

-15 5 406.7 25 77 54.89 65 149 11.38 105 221 3.203

-14 7 384.3 26 79 52.53 66 151 10.99 106 223 3.113

-13 9 363.3 27 81 50.28 67 153 10.61 107 225 3.025

-12 10 343.6 28 82 48.14 68 154 10.25 108 226 2.941

-11 12 325.1 29 84 46.11 69 156 9.902 109 228 2.86

-10 14 307.7 30 86 44.17 70 158 9.569 110 230 2.781

-9 16 291.3 31 88 42.33 71 160 9.248 111 232 2.704

-8 18 275.9 32 90 40.57 72 162 8.94 112 234 2.63

-7 19 261.4 33 91 38.89 73 163 8.643 113 235 2.559

-6 21 247.8 34 93 37.3 74 165 8.358 114 237 2.489

-5 23 234.9 35 95 35.78 75 167 8.084 115 239 2.422

-4 25 222.8 36 97 34.32 76 169 7.82 116 241 2.357

-3 27 211.4 37 99 32.94 77 171 7.566 117 243 2.294

-2 28 200.7 38 100 31.62 78 172 7.321 118 244 2.233

-1 30 190.5 39 102 30.36 79 174 7.086 119 246 2.174
0 32 180.9 40 104 29.15 80 176 6.859 120 248 2.117
1 34 171.9 41 106 28 81 178 6.641 121 250 2.061
2 36 163.3 42 108 26.9 82 180 6.43 122 252 2.007
3 37 155.2 43 109 25.86 83 181 6.228 123 253 1.955
4 39 147.6 44 111 24.85 84 183 6.033 124 255 1.905
5 41 140.4 45 113 23.89 85 185 5.844 125 257 1.856
6 43 133.5 46 115 22.89 86 187 5.663 126 259 1.808
7 45 127.1 47 117 22.1 87 189 5.488 127 261 1.762
8 46 121 48 118 21.26 88 190 5.32 128 262 1.717
9 48 115.2 49 120 20.46 89 192 5.157 129 264 1.674
10 50 109.8 50 122 19.69 90 194 5 130 266 1.632
11 52 104.6 51 124 18.96 91 196 4.849
12 54 99.69 52 126 18.26 92 198 4.703
13 55 95.05 53 127 17.58 93 199 4.562
14 57 90.66 54 129 16.94 94 201 4.426
15 59 86.49 55 131 16.32 95 203 4.294
16 61 82.54 56 133 15.73 96 205 4.167
17 63 78.79 57 135 15.16 97 207 4.045
18 64 75.24 58 136 14.62 98 208 3.927
19 66 71.86 59 138 14.09 99 210 3.812

51

Appendix 3:

°C °F °C °F °C °F °C °F °C °F

-5 23 21 69.8 51 123.8 82 179.6 113 235.4

-4 24.8 22 71.6 52 125.6 83 181.4 114 237.2

-3 26.6 23 73.4 53 127.4 84 183.2 115 239

-2 28.4 24 75.2 54 129.2 85 185 116 240.8

-1 30.2 25 77 55 131 86 186.8 117 242.6
0 32 25.5 77.9 56 132.8 87 188.6 118 244.4

0.5 32.9 26 78.8 57 134.6 88 190.4 119 246.2
1 33.8 27 80.6 58 136.4 89 192.2 120 248

1.5 34.7 28 82.4 59 138.2 90 194 121 249.8
2 35.6 29 84.2 60 140 91 195.8 122 251.6

2.5 36.5 30 86 61 141.8 92 197.6 123 253.4
3 37.4 31 87.8 62 143.6 93 199.4 124 255.2

3.5 38.3 32 89.6 63 145.4 94 201.2 125 257
4 39.2 33 91.4 64 147.2 95 203 126 258.8

4.5 40.1 34 93.2 65 149 96 204.8 127 260.6
5 41 35 95 66 150.8 97 206.6 128 262.4
6 42.8 36 96.8 67 152.6 98 208.4 129 264.2
7 44.6 37 98.6 68 154.4 99 210.2 130 266
8 46.4 38 100.4 69 156.2 100 212 131 267.8
9 48.2 39 102.2 70 158 101 213.8 132 269.6

10 50 40 104 71 159.8 102 215.6 133 271.4
11 51.8 41 105.8 72 161.6 103 217.4 134 273.2
12 53.6 42 107.6 73 163.4 104 219.2 135 275
13 55.4 43 109.4 74 165.2 105 221 136 276.8
14 57.2 44 111.2 75 167 106 222.8 137 278.6
15 59 45 113 76 168.8 107 224.6 138 280.4
16 60.8 46 114.8 77 170.6 108 226.4 139 282.2
17 62.6 47 116.6 78 172.4 109 228.2 140 284
18 64.4 48 118.4 79 174.2 110 230 141 285.8
19 66.2 49 120.2 80 176 111 231.8 142 287.6
20 68 50 122 81 177.8 112 233.6 143 289.4

52

2.Compressor checking

Measure the resistance value of each winding by using the tester.

Position Resistance Value
ASN98D22UEZ ASM135D23UFZ DA150S1C-20FZ(F)
Blue - Red

1.57Ω

(20℃/68℉)

1.75Ω

(20℃/68℉)

0.95Ω

(20℃/68℉)

Blue - Black
Red - Blue

53

3. IPM continuity check

Turn off the power, let the large capacity electrolytic capacitors discharge completely, and dismount the IPM. Use a digital
tester to measure the resistance between P and UVWN; UVW and N.

Digital tester Normal resistance value

Digital tester Normal resistance value

(+)Red (-)Black

∞

(Several MΩ)

(+)Red (-)Black

∞

(Several MΩ)

P

N U

N

U V
V W

W (+)Red

4.Indoor AC Fan Motor
Measure the resistance value of each winding by using the tester.

Position Resistance Value

RPG20E(YKFG-20-4-5) RPG28D(YKFG-28-4-1) RPG45C(YKFG-45-4-22)

Black - Red 388Ω±8% (20℃)

(Brand: Weiling)

260Ω±8% (20℃)

(Brand: Weiling)

168Ω±8% (20℃)

(Brand: Weiling)

White - Black

360Ω±8% (20℃)

(Brand: Weiling)

385Ω±8% (20℃)

(Brand: Weiling)

141Ω±8% (20℃)

(Brand: Weiling)

54

5: Pressure On Service Port

Cooling chart:

°F(°C)

O

DT

IDT

75

(23.89)

85

(29.44)

95

(35)

105

(40.56)

115

(46.11)
BAR 70/59 8.2 7.8 8.1 8.6 10.1
BAR 75/63 8.6 8.3 8.7 9.1 10.7
BAR 80/67 9.3 8.9 9.1 9.6 11.2

°F(°C)

O

DT

IDT

75

(23.89)

85

(29.44)

95

(35)

105

(40.56)

115

(46.11)
PSI 70/59 119 113 117 125 147
PSI 75/63 124 120 126 132 155
PSI 80/67 135 129 132 140 162

°F(°C)

O

DT

IDT

75

(23.89)

85

(29.44)

95

(35)

105

(40.56)

115

(46.11)
MPA 70/59 0.82 0.78 0.81 0.86 1.01
MPA 75/63 0.86 0.83 0.87 0.91 1.07
MPA 80/67 0.93 0.89 0.91 0.96 1.12

0.0

2.0

4.0

6.0

8.0

10.0

12.0

75 （23.89） 85 （29.44） 95 （35） 105 （40.56） 115 （46.11）

70/59
75/63
80/67

55

Heating Chart:

°F

(°C)

O

DT

IDT

57/53

(13.89/11.67)

47/43

(8.33/6.11)

37/33

(2.78/0.56)

27/23

(-2.78/-5)

17/13

(-8.33/-10.56)
BAR 55 30.3 28.5 25.3 22.8 20.8
BAR 65 32.5 30.0 26.6 25.4 23.3
BAR 75 33.8 31.5 27.8 26.3 24.9

°F

(°C)

ODT

IDT

57/53

(13.89/11.67)

47/43

(8.33/6.11)

37/33

(2.78/0.56)

27/23

(-2.78/-5)

17/13

(-8.33/-10.56)
PSI 55 439 413 367 330 302
PSI 65 471 435 386 368 339
PSI 75 489 457 403 381 362

°F

(°C)

O

DT

IDT

57/53

(13.89/11.67)

47/43

(8.33/6.11)

37/33

(2.78/0.56)

27/23

(-2.78/-5)

17/13

(-8.33/-10.56)

MPA

55 3.03 2.85 2.53 2.28 2.08

MPA

65 3.25 3.00 2.66 2.54 2.33

MPA

75 3.38 3.15 2.78 2.63 2.49

0.0

5.0

10.0

15.0

20.0

25.0

30.0

35.0

40.0

57/53

(13.89/11.67)

47/43

(8.33/6.11)

37/33

(2.78/0.56)

27/23

(-2.78/-5)

17/13

(-8.33/-10.56)

55
65
75

56

10 Disassembly Instructions

Note: This part is for reference, the photos may have slight difference with your machine.

10.1 Indoor unit

No. Parts name Procedures Remarks

1 Front panel

How to remove the front panel.

1) Pull the below side of
the panel toward you and
remove the cover

2) Release the connector of

the display ass’y.

3) Release the two clips and

then remove the panel.

4) Remove the filter and the

horizontal louver.

5) Remove the two screws

and then remove the panel
ass’y.

②

⑤

57

2 Electrical

parts

How to remove the electrical
parts.

1) Remove the front
panel from procedure 1.

2) Pull out the room temp.
sensor (T1). Remove the two
screws for the ground
connection.

3) Remove the fixing screw.

4) Pull out the coil temp.

sensor.

5) From the side direction,

open the electronic control box
cover fixing by clips. Pull out
the fan motor connector and
swing motor connector. Then
remove the electronic control
box.

②

③

④

⑤

②

58

3 Evaporator

How to remove the evaporator.

1) After remove the
electrical parts from procedure
2, disassemble the pipe holder
at the rear side of the unit.
.

2) Remove the screws on the
evaporator at the fixed plate.

3) Remove the two screws
on the evaporator at the base
bearing side.

4) Then pull out the
evaporator.

③

①

②

59

4 Fan motor

and Fan

How to remove the fan motor.

1) Remove the front
panel, electrical parts and
evaporator following procedure
1-3.

2) Remove the two screws

and remove the fixing board of
fan motor.

3) Remove the fixing screw .

4) Pull out the fan motor and

fan ass’y from the side
direction.

②

③

60

10.2 Outdoor unit

Ø MOB1-12CDN1-MP0W

No. Part name Procedures Remarks

1 Panel plate

How to remove the panel plate.

1) Stop operation of the
air conditioner and turn “OFF”
the power breaker.

2) Remove the top
cover.(8 screws)

3) Remove the front
panel.(10 screws)

4) Remove the side
panel.(11 screws)

2 Fan ass’y

How to remove the fan ass’y.

1) Remove the panel
plate from procedure 1

2) Remove the hex nut
fixing the fan.

3) Remove the fan.

4) Disconnect the
connector for fan motor from
the electronic control board.

5) Remove the fixing
screws.(4 pcs)

6) Remove the fan motor.

⑤

4screws

Side panel

Front panel

Top cover

②

④

③

61

3 Electrical

parts

How to remove the electrical
parts.

1) Perform work of item
1,2.

2) Remove the wires
connected with the
compressor. (On the IPM )

3) Remove the wires
connected with 4-way valve.

4) Remove the red wire
connected with the capacitor
Remove the blue wire
connected with the reactor.

5) Remove the temp. sensor
connectors. Remove the
ground wire
of the compressor

6) Remove the two fixing
screws

7) Remove the electronic
control box.

4 Compressor

How to remove the

⑦

⑤

③

Two blue
wires

④

②

⑥

62

compressor.

1) Perform work of item
1,2,3.

2) Remove ground wire and
remove the discharge pipe
and suction pipe with a burner.

3) Remove the nuts and
washers fixing the compressor
on bottom plate.

4) Lift the compressor
from the base pan assembly.

②

③

63

Ø MOC-18CDN1-MP0W

No. Part name Procedures Remarks

1 Panel plate

How to remove the panel plate.

1) Stop operation of the
air conditioner and turn “OFF”
the power breaker.

2) Remove the top
cover.(6 screws)

3) Remove the front
panel.(10 screws)

4) Remove the side
panel.(10 screws)

2 Fan ass’y

How to remove the fan ass’y.

1) Remove the panel
plate from procedure 1

2) Remove the hex nut
fixing the fan.

3) Remove the fan.

4) Disconnect the
connector for fan motor from
the electronic control board.

5) Remove the fixing
screws.(4 pcs)

6) Remove the fan motor.

3 Electrical

parts

How to remove the electrical

②

⑤

4 screws

③

④

64

parts.

1) Perform work of item
1,2.

2) Remove the two
connectors for the compressor
and the reactors.

3) Remove two blue wires
connected with the four way
valve.

4) Remove the connectors
for the condenser coil temp.
sensor(T3),outdoor ambient
temp. sensor(T4) and
discharge temp. sensor(T5).
(two black connectors, one
white connector)

5) Remove the ground
wires .

6) Remove the fixing screws.

7) Remove the electronic
control box.

4 Compressor

How to remove the
compressor.

④

T3,T4,T5

③

②

⑥

two screws

⑤

65

1) Perform work of item
1,2,3.

2) Remove the ground wire
and remove the discharge
pipe and suction pipe with a
burner.

3) Remove the hex nuts
and washers fixing the
compressor on bottom plate.

4) Lift the compressor

from the base pan assembly.

③

②

66

Ø MOF1-22CDN1-MP5W

No.

Parts name Procedures

Remarks

1

Panel plate How to remove the panel plate.

1) Stop operation of the
air conditioner and turn “OFF”
the power breaker.

2) Remove the top
cover.(9 screws)

3) Remove the front
panel.(2 screws)

4) Remove the side
panel.(10 screws)

5) Remove the air
outlet panel.(9 screws)

2

Fan ass’y How to remove the fan ass’y.

1) Remove the panel
plate from procedure 1.

2) Remove the hex nut
fixing the fan.

3) Remove the fan.

4) Disconnect the
connectors for fan motor from
the electronic control board.
(There are blue wire, red wire
and black wire. The blue wire
and red wire are on the
capacitor. The black wire is
connected with terminal four.)

5) Remove the fixing
screws.(3 pcs)

Side panel

Air outlet panel

Front panel

Top cover

②

④

3 pcs wires.

③

67

6) Remove the fan
motor.

3

Electrical
parts

How to remove the electrical
parts.

1) Perform work of item
1,2.

2) Remove the screw on
the middle metal plate.

3) Remove the wires
connected with the
compressor.(Red wire
connects with terminal one, the
blue wire and white wire
connect with the compressor
capacitor)

4) Remove the wires
connected with the 4-way
valve.

5) Remove the electrical
parts.

⑤

3 screws

②

③

3 pcs wires.

68

4

Compressor How to remove the

compressor.

1) Perform work of item
1,2,3.

2) Remove the ground wire
and remove the discharge pipe
and suction pipe with a burner.

3) Remove the nuts and
washers fixing the compressor
on bottom plate.

4) Lift the compressor
from the base pan assembly.

④

③