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Page 54
6. Troubleshooting
6-1 Items to be checked first
1. The input voltage should be rating voltage ±10% range.
The airconditioner may not operate properly if the voltage is out of this range.
2. Is the link cable linking the indoor unit and the outdoor unit linked properly?
The indoor unit and the outdoor unit shall be linked by 4 wires.
2 wires are for power and other 2 wires are for communication, total 4 wires on each indoor unit. Check the terminals if the indoor
unit and outdoor unit are properly linked by the same number of cables and if connecting position on the terminal is correct.
Otherwise the airconditioner may not operate properly.
3. When a problem occurs due to the contents illustrated in the table below it is a symptom not related to the malfunction of the
airconditioner.
No
54
Operation of air conditioner
Explanation
1
In a COOL operation mode, the compressor does not
operate at a room temperature higher than the setting
temperature that the INDOOR FAN should operate.
In a HEAT operation mode, the compressor does not
operate at a room temperature lower than the setting
temperature that indoor fan should operate.
In happens after a delay of 3 minutes when the compressor is
reoperated. The same phenomenon occurs when a power is on.
As a phenomenon that the compressor is reoperated after a delay
of 3 minutes, the indoor fan is adjusted automatically with reference to a temperature of the air blew
2
Fan speed setting is not allowed in AUTO(
DRY(
) mode.
The speed of the indoor fan is set to LL in DRY mode.
Fan speed is 5 steps and is selected automatically in AUTO mode.
3
Compressor stops operation intermittently in
DRY(
) mode.
Compressor operation is controlled automatically in DRY mode
depending on the room temperature and humidity.
4
Compressor of the outdoor unit is operating although
it is turned off in a HEAT mode.
When the unit is turned off while de-ice is activated, the
compressor continues operation for up to 12 minutes (maximum)
until the deice is completed.
5
Timer LED(
) only of the indoor unit lights up and
the air conditioner does not operate.
Timer is being activated and the unit is in ready mode.
The unit operates normally if the timer operation is cancelled.
6
The compressor and indoor fan stop intermittently in
HEAT mode.
The compressor and indoor fan stop intermittently if room
temperature exceeds a setting temperature in order to protect the
compressor from overheated air in a HEAT mode.
7
Indoor fan and outdoor fan stop operation
intermittently in a HEAT mode.
The compressor operates in a reverse cycle to remove
exterior ice in a HEAT mode, and indoor fan and outdoor fan
do not operate intermittently for within 20% of the total heater
operation.
8
The compressor stops intermittently in a
COOL mode or DRY mode, and fan speed of the
indoor unit decreases.
The compressor stops intermittently or the fan speed of the indoor
unit decreases to prevent inside/outside air frozen depending on
the inside/outside air temperature.
) or
Samsung Electronics
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Page 55
6-2 Checking and Testing operations
To complete the installation, perform the following checks and tests to ensure that the air conditioner is operating correctly.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
Review all the following elements in the installation:
• Installation site strength
• Piping connection tightness not to leak any gas
• Connection wiring
• Heat-resistant insulation of the piping
• Drainage
• Earthing wire connection
• Setting number of the indoor unit installed (Outdoor unit SW)
• Addressing mode (AUTO or MANUAL)
• Address number on each indoor unit (Manual addressing mode)
• Correct operation for checking connection (follow the step below)
AUTO
Addressing
1
MANUAL
Addressing
2
3
4
Number of
indoor unit
7 segment
LED
2digits x 2
K1
K2
K3
K4
2. ■ Key Options of PCB Display
2. ■ - K1 : Test button
- K2 : Function button
2. ■ - K3 : Reset button
- K4 : View mode change button
Key
K1
K2
Heat mode
Try-run
(Display:
)
Refrigerant
Charging
(Display:
)
-
Cool mode
Try-run
(Display:
)
K3
SW02
K4
SW01
Push
1
2
(OFF)
DIS01
Indoor unit
address
K1
Reset
3
-
Pump down
(Display:
)
-
Checking of
pipe connection
(Display:
)
DIS02
View mode
change
K2
K3
K4
View data display
Outdoor PCB Display
4
2. ■ K4 View mode Display changes
Push
Display Explanation
Push
Display Explanation
0
Present Compressor Frequency
8
Discharge temperature
1
Target Compressor Frequency
9
OLP temperature
2
Order Compressor Frequency
10
Condenser temperature
3
EEV0 current step
11
Outdoor temperature
4
EEV1 current step
12
Primary current
5
EEV2 current step
13
Target Discharge temperature
6
EEV3 current step
14
Total capacity of the indoor units
7
Fan RPM (H: high, L: low, Blank: off)
15
Safety control code
Samsung Electronics
MH18VP2X/ MH19VP2X /MH052FXEA2
Always Zero
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Troubleshooting
2. Apply the power to the outdoor unitutdoor unit will try to communicate the specified number of indoor units
Outdoor unit will try to communicate the specified number of indoor units bySW01onoutdoordisplayPCB.
Does LED show "Normal display"?
"Normal display" means, right 2 digit of
LED on Display PCB displays '00' and
left 2 digit of LED displays indoor unit
address number.
Yes
OK : This number is displayed
only while communicating,
so each number is displayed
for a short time in order.
Yes
Is error code started with ''
displayed on the LED?
No
''
Nothing is displayed on the LED.
Yes
Check the indoor unit, outdoor unit or wiring
according the error code table.
Check the power source,
power cable & FUSE on
the outdoor unit.
2. ■ In case of AUTO ADDRESSING mode (SW2-1:ON)
Press K2 switch 4 times to start
"PIPE CHECK MODE". After starting this
mode, LED on the left is displayed "K5"
• Press K2 switch once to cancel this mode.
• During this mode LED on the right 2 digit
shows EEV number and the indoor address
which is checking at the time.(See right figure)
Yes
"PIPE CHECK MODE" finished without error
: It takes 5 to 50 minutes to complete.
(This time depends on the outdoor
temperature and number of indoor unit.)
K5
Yes
EEV Indoor
number unit
0,1,2,3 Address
OK : LED shows
"Normal display" & press K3
to restart the system.
LED display under PIPE CHECK MODE
Yes
If finished with error, Right digit will show
the EEV number which is the wrong PIPE
connection. In case of two or more wrong
connection, error EEV number will display
each for 1 second in order.
No
display
Yes
After Comfirm the error,
press K3 to system reset.
No
Do this mode again.
Error EEV
number
0,1,2,3
LED display when PIPE CHECK ERROR
- This mode is for finding the combination between indoor unit and each valve on the outdoor unit. Because refrigerant flow is
controlled with EEV in the outdoor,controller should know which EEV will control which indoor unit.
- Once "PIPE CHECK MODE"is done normally,each indoor unit will remember the given address number by the outdoor unit and
no need to do this checking. But in case of listed below,PIPE CHECK MODE should be done again.
2. - • Re-install the system (ie.house moving)
2. - • Remove indoor unit,Add new indoor unit,Change indoor PCB for repair.
2. - • Mode change from "manual addressing"to "auto addressing"
- On this mode the controller will ignore the manual address number set on the rotary switch on the indoor PCB.
- To confirm the indoor address number assigned by this mode,use "TEST MODE"and the address number will be displayed on the
LED display on the indoor unit.
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Troubleshooting
■ In case of MANUAL ADDRESSING mode. (SW02-1:OFF)
2. ■ Checking the address number correctly on each indoor unit PCB.
2. ■ - "PIPE CHECK MODE" is also able to use.
● If Error code is displayed on indoor or outdoor LED, check as follows;
SW01 setting number and the number of
indoor unit installed are the same.
Yes
SW01 setting number must same
as the number of indoor unit.
Yes
Check communication wire and
power wire connection.
Yes
Check PIPE connection,
because gas flow to a different
indoor unit will cease these error.
Yes
Comfirm power cable connection,
especially miss-wiring between
communication cable and
power cable.
Yes
Some indoor unit has no power.
No
Error code E101 or E185 is displayed on
indoor unit LED
AC power line could be
connected to outdoor
communication terminal,
F1&F2. So check the wiring not
only communication line but
also power line.
No
Yes
Error code E460 is displayed on
outdoor unit LED.
No
Error code E401, E404 or E416 is
displayed on outdoor unit LED.
No
In case of communication error by
wrong wiring on the indoor unit,
all indoor units display an error code.
In this case, correction at the wrong point
could solve all indoor unit error display.
9K or 12K BTU
indoor PCB
Address
number
switch
18K BTU indoor PCB
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Troubleshooting
The error indicated on the PCB display of outdoor unit
Display
58
Explanation
Main checking Point
Communication error (indoor unable to receive data)
Communication cable
connection
Communication error (outdoor unable to communicate)
Indoor unit
Indoor unit room temperature sensor error (Open/Short)
Indoor unit
Indoor unit heat exchanger in temperature sensor error (Open/Short)
Indoor unit
Indoor unit heat exchanger out temperature sensor error (Open/Short)
Indoor unit
Indoor unit sensor error - Evaporator pipe in sensor detached
Indoor unit
Indoor unit sensor error - Evaporator pipe out sensor detached
Indoor unit
Indoor unit heat exchanger in & out temperature sensor detached
Indoor unit
More than 2 indoor units cool and heat simultaneously
Indoor unit operation
mode
The number of indoor unit mismatched
Communication wiring
Communication error (outdoor unable to receive data)
Communication wiring
Communication error between 2 microcontroller on the outdoor PCB
Outdoor unit PCB
Outdoor temperature sensor error (Short/Open)
- Error level : over 4.9V(-50˚C) under 0.4V(93˚C)
Temperature sensor
Condenser temperature sensor error (Short/Open)
- Error level : over 4.9V(-50˚C) under 0.4V(93˚C)
Temperature sensor
Condenser temperature sensor detached
Temperature sensor
Compressor discharge sensor error (Short/Open)
- Error check condition : outdoor temperature over -20˚C
- Error level : over 4.95V(-30˚C) under 0.5V(151˚C)
Temperature sensor
Compressor discharge sensor detached
Temperature sensor
Compressor OLP sensor error (Short/Open)
- Error check condition : outdoor temperature over -20˚C
- Error level : over 4.95V(-30˚C) under 0.5V(151˚C)
Temperature sensor
Indoor unit heat exchanger freezing and compressor stop (cooling mode)
Check pipe matching
also(indoor-outdoor)
Outdoor unit overload and compressor stop (protection control in heating mode)
Check pipe matching
also(indoor-outdoor)
Outdoor unit high discharge temperature and compressor stop
(protection control in heating mode)
Check pipe matching
also(indoor-outdoor)
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Troubleshooting
The error indicated on the PCB display of outdoor unit(cont.)
Display
Samsung Electronics
Explanation
Main checking Point
Outdoor unit EEV open error (self diagnosis)
EEV
Outdoor unit EEV close error (self diagnosis)
EEV
High temperature (over 30˚C) of outdoor as heating mode
Operation mode
Low temperature (under -5˚C) of indoor as cooling mode
Operation mode
Wrong connection between communication and power cable
Wiring indoor and outdoor
Inverter compressor starting failure (5 times)
Service valve, EEV,
Compressor terminal,
Compressor wire,
Outdoor controller
Compressor trip by input current limit control
EEV, Gas over charge,
Outdoor controller
Compressor trip by OLP temperature limit control
Outdoor fan, Compressor,
Outdoor controller
Compressor peak current protection
Outdoor fan, Compressor,
Compressor wire,
Outdoor controller
Compressor overload protection by current
Outdoor fan, EEV,
Service valve,
Outdoor controller
DC-link voltage error (under 150V or over 410V)
(This error might display for a few seconds after power cut)
Power voltage,
Outdoor controller
Compressor rotation error
Compressor terminal,
Compressor wire,
Outdoor controller
Current sensor error
Outdoor controller
DC-link voltage sensor error
Outdoor controller
Compressor overload protection
Outdoor fan, EEV,
Service valve,
Outdoor controller
EEPROM error
Outdoor controller
AC line zero-crossing detection circuit error
Outdoor controller,
Terminal Block
NO GAS error (self diagnosis)
Piping (gas leak)
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Troubleshooting
The error indicated on the LED display of Indoor unit
■ MH020FPEA / MH023FPEA / MH026FPEA / MH035FPEA / MH052FPEA / MH18VP2-09 / MH19VP2-07 / MH19VP2-12
Display
60
Explanation
Main checking Point / Remark
Communication error (unable to receive data)
Communication cable connection
Communication error (outdoor cannot communicate)
Another indoor unit or indoor PCB
Indoor unit room temperature sensor error (Open/Short)
Room temperature sensor, indoor PCB
Indoor unit heat exchanger in temperature sensor error (Open/Short)
Heat exchanger in sensor, indoor PCB
Indoor unit heat exchanger out temperature sensor error (Open/Short)
Heat exchanger out sensor, indoor PCB
Indoor unit heat exchanger in temperature sensor detached
Heat exchanger in sensor
Indoor unit heat exchanger out temperature sensor detached
Heat exchanger out sensor
Indoor unit heat exchanger in & out temperature sensor detached
Heat exchanger in & out sensor
Indoor unit fan motor malfunction
Fan motor and cable
More than 2 indoor units cool and heat simultaneously
Another indoor unit operation mode
EEPROM error
Indoor PCB
Option code setting error
Option code
Cable miss-wiring
Cable connection (Indoor & Outdoor unit)
The number of indoor unit mismatched
Cable connection (another indoor unit &
outdoor unit), SW01(outdoor)
Outdoor unit error
Outdoor unit (Error code)
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05/2/21 11:58 PM
Page 61
Troubleshooting
The error indicated on the LED display of Indoor unit
■ MH026FKEA / MH035FKEA
Indicators
Abnormal conditions
Operating
Green
Red
Power reset
Error of temperature sensor in indoor unit (OPEN/SHORT)
Error of heat exchanger sensor in indoor unit
Error of heat exchanger OUT sensor in indoor unit
Error of outlet temperature sensor in indoor unit
(OPEN/SHORT): For heat pump models only
Error of mixed operation
Error of indoor fan motor : Below 450RPM for 15 minutes
Error of outdoor temperature sensor
Error of COND sensor
Error of DISCHARGE sensor
1. No communication for 2 minutes between indoor unit and
outdoor unit (communication error for more than
2 minutes)
2. Indoor unit receiving the communication error from
outdoor unit
Error of indoor unit:
Displayed on the indoor
unit regardless of
operation
3. Outdoor unit tracking 3 minutes error
4. When sending the communication error from outdoor unit
due to the mismatching of the communication numbers
and installed numbers after completion of tracking
(communication error for more than 2 minutes)
1. 2nd detection of refrigerant completely leak
2. 2 detection of high temperature COND
nd
3. 2nd detection of high temperature DISCHARGE
4. Compressor down due to 6th detection of freezing
Displayed on appropriate
indoor unit which is
operating
Displayed on outdoor
unit
Error of float switch
Error of setting option switches for optional accessories
EEPROM error
EEPROM option error
: On
: Flickering
: Off
◆ If you turn off the air conditioner when the LED is flickering, the LED is also turned off.
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Troubleshooting
The error indicated on the LED display of Indoor unit
■ MH052FDEA
Indicators
Concealed Type
Abnormal conditions
Blue
Red
Operating
Standard Type
Power reset
Error of temperature sensor in indoor unit (OPEN/SHORT)
Error of heat exchanger sensor in indoor unit
Error of heat exchanger OUT sensor in indoor unit
Error of outlet temperature sensor in indoor unit
(OPEN/SHORT): For heat pump models only
Displayed on appropriate
indoor unit which is
operating
Displayed on appropriate
indoor unit which is
operating
Error of mixed operation
Error of outdoor temperature sensor
Error of COND sensor
Error of DISCHARGE sensor
1. No communication for 2 minutes between indoor unit and
outdoor unit (communication error for more than
2 minutes)
2. Indoor unit receiving the communication error from
outdoor unit
3. Outdoor unit tracking 3 minutes error
4. When sending the communication error from outdoor unit
the mismatching of the communication numbers and
installed numbers after completion of tracking.
(communication error for more than 2 minutes)
Self-diagnostic error
(including the indoor unit not detected)
1. Error of electronic expansion valve close
2. Error of electronic expansion valve open
3. Breakaway of EVA OUT sensor
Displayed on appropriate
indoor unit which is
operating
Displayed on outdoor
unit
1. Error of indoor unit :
Displayed on the
indoor unit regardless
of operation
2. Error of outdoor unit :
Displayed on the
indoor unit which is
operating
Displayed on appropriate
indoor unit which is
operating
Displayed on outdoor
unit
4. Breakaway of EVA IN sensor
: On
: Flickering
: Off
◆ If you turn off the air conditioner when the LED is flickering, the LED is also turned off.
◆ If you re-operate the air conditioner, it operates normally at first, then detect an error again.
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Troubleshooting
Indicators
Concealed Type
Abnormal conditions
Blue
Red
Operating
Standard Type
5. Breakaway of COND MID sensor
6. 2 detection of refrigerant completely leak
nd
7. 2nd detection of high temperature COND
8. 2nd detection of high temperature DISCHARGE
Displayed on appropriate
indoor unit which is
operating
Displayed on outdoor
unit
9. COMP DOWN due to 2nd detection of low pressure
switch
10. Error of reverse phase
11. Compressor down due to 6th detection of freezing
12. Self-diagnosis of condensation sensor (G8, G9)
13. Compressor down due to condensation ratio control
Error of float switch
Error of setting option switches for optional accessories
EEPROM error
EEPROM option error
: On
: Flickering
: Off
◆ If you turn off the air conditioner when the LED is flickering, the LED is also turned off.
◆ If you re-operate the air conditioner, it operates normally at first, then detect an error again.
Samsung Electronics
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6-3 Fault Diagnosis by Symptom
6-3-1 Basic Check Flow
Preparation : multimeter (AC voltage, DC voltage, Resistance)
START
Short check
for safety
Check point
Detach cable cover of the terminal blocks
(HANDLE CABI HR) on outdoor unit.
Check resistance value between
L and N of Main power terminal block.
No Good
• Outdoor unit controller (see 6-3-2)
• Indoor unit controller (see 6-3-3)
No Good
• Power cable (see 6-3-4, 6-2)
• Breaker
OK : over 180KΩ
Apply the power
Power Source
check
Check AC voltage between L and N of
MAIN power terminal block.
OK : 207-253V(50Hz)
Check AC voltage between L and N of
power terminal block for indoor unit.
Outdoor unit
No Good
Terminal block wiring
OK : 207-253V
Is there any display of LED?
No
Yes
No Good
Start operation
Any Error code on LED display?
Wait for 5 minutes to check error
code because some error judgement
needs long time.
• Main PCB,
• Display PCB,
• wiring between PCBs.
Starting by remocon or ON/OFF switch on the indoor
unit or K2 buttom on the Outdoor PCB display.
Yes
Error code starts in ''
''
Consult error code table
No
Indoor unit
Receiving of remote control signal ?
(Check by buzzer sound)
No
• Remote control
• Remote control battery
• Infrared signal receiving path
(front panel durt, infrared receiving module, wiring)
Yes
Check operation ON/OFF by the button
at lower right of the display module
(By buzzer sound and LED display)
Ok
Any Error code on LED display?
Wait for 5 minutes to check error code
because some error judgement
needs long time
No
• Indoor unit,
• Wiring cabe to outdoor unit
Yes
Error code starts in '' ''.
Error code consists of 4 digits and displays first 2
digit and last 2 digit alternatively.
Consult error code table
Check Major parts(See 6-5)
Consult error code(Next Page)
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Troubleshooting
Consult Error Code
Check point
,
,
,
,
Is the error code related to
communication ?
,
• Cable wiring between indoor and outdoor
• Communication wire socket check on
outdoor unit controller PCB
No
Is the error code related to
cycle protection ?
,
• Cycle check
• Pipe matching
No
Are some of the indoor units’
operation mode (cooling/heating)
different from othres ?
,
Each indoor unit operation mode
No
Error related to outdoor controller except
temperature sensor and communication
between indoor unit and outdoor unit ?
--
Consult LED pattern on wiring diagram on
outdoor controller
No
See Error Code Table and Check
“Main checking point”
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Troubleshooting
6-3-2 Checking Outdoor Controller
1. Making sure the wire connections.
Live side
2. Checking AC line
1) Checking FUSE
2) Checking resistance between 'L wire (BRN)' and 'DB01 Live side'
normal value : 190 - 210Ω
If value is ∞ then check R001.
3) Checking resistance between 'N wire (SKYBLU)' and 'DB01 Neutral side'
normal value : 0 - 0.1Ω
Neutral side
BD01
3. Checking ON/OFF pattern of LED1(Red), LED2(Green), LED3(Yellow)
Apply the power then ALL LEDs are on for about 1 second. then changed to as follow.
■ LED1 (Red) : ALWAYS ON
■ LED2 (Green) : Blinking 4 times a second
(This means communication between 2 micoms IC01 and IC50 is normal)
■ LED3 (Yellow) : OFF
● In case of another pattern inverter micom detects some hardware trouble or abnormal condition.
Yellow
Green
Red
Description
Note
Status indication
OFF
OFF
OFF
Power OFF / No power (SMPS error)
ON
ON
ON
Power on reset ( 1~2 seconds )
OFF
Blink
ON
Normal operation
If always in this pattern IC01(inverter micom)
has some trouble.
Hardware trouble
OFF
OFF
ON
Communication Error between
Main micom and inverter micom
Blink
Blink
ON
Current sensor error
ON
Blink
Blink
DC-LINK sensor error
ON
ON
Blink
AC-Line zero crossing error
ON
OFF
Blink
Option error (EEPROM error)
After power off this error will display until
DC LINK capacitor discharged.(Max 20sec.)
Abnormal condition
66
OFF
OFF
Blink
Comp. peak current (Over Current)
OFF
Blink
OFF
Comp. starting error
ON
OFF
ON
Comp. rotation error
OFF
ON
Blink
DC-Link voltage error
Blink
ON
OFF
Unit Over current protection
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Troubleshooting
4. Checking Display PCB LED if Error code is displayed.
See error code table if displayed.
5. Checking DC voltage on each point
Item
Measuring point
Normal value
Q803 E(-)~D101 Cathode (+)
about 1.4 times as much as Power AC Voltage
ex) AC220V → 305~310Vdc
C803 voltage
14.5V~15.5V
Main control 12V
CN59 pin 1~pin 3
12V~15V
Main control 5V
CN59 pin 1~pin 2
4.75V~5.25V
DC LINK
inverter 15V
6. Checking PFC
6. When Input current is over 3.0A PFC circuit will work to control the harmonics of AC current.
Checking is measuring DC-LINK voltage.
PFC ON (Compressor is working) : DC LINK voltage is over 300Vdc (AC line >220V )
After starting compressor DC Link voltage is going down because of compressor load.
But in case of 3.0A above , DC link voltage will go up over 300V. This voltage is in proportion to AC input voltage.
Current can be monitored with "VIEW MODE".
Press K4 key on the outdoor display PCB for several times to change the display to sensor temperature value.
Left 1 digit of the LED is data index and Right 3 digits are the value
Index
C
Samsung Electronics
Value
Estimated Primary current value from
Compressor current
Remark
The unit is 0.1A
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Troubleshooting
6-3-3 Checking Indoor controller
1. MH020FPEA /MH023FPEA /MH026FPEA/MH035FPEA/MH18VP2-09/MH19VP2-07/MH19VP2-12 PCB
1.
1.
1.
1.
1.
1.
1) Checking FUSE
1) This control PCB has 2 fuses, F701 and F702.
1) If F702 is blown PCB circuit has some damage and replace PCB.
2) Checking DC voltage
■ Measure voltage between CN43 pin 1 (+12V) and CN43 pin 2 (GND).
■ Normal voltage is between 11.5V and 12.5V.
2. 18K BTU (MH052FPEA) PCB
1.
1.
1.
1.
1.
1.
1.
1) Checking FUSE
1) The fuse F701 is located on the inner side AC PCB.
2) Checking DC Voltage
1) Measure voltage between CN43 pin 1 (+12V) and CN43 pin 2 (GND) on the outer side PCB.
1) Normal voltage is between 11.5V and 12.5V.
1) DC voltage is supplied from CN90 on the inner AC PCB. Pin layout is as follows.
1) Pin 7 : GND, Pin 8 : +5V, Pin 9 : +12V
6-3-4 Checking Power cable and Communication cable
See 6-2 "Checking and Testing operations" and installation manual.
6-3-5 Checking Temperature sensor
See 6-5 "Fault Diagnosis of Major Parts".
In case of a sensor in outdoor unit, temperature can be monitored with "VIEW MODE".
Press K4 key on the outdoor display PCB for several time to change the display to sensor temperature value.
Left 1 digit of the LED is data index and Right 2 digits are the value.
Index
68
Value
8
Discharge sensor temperature
9
OLP sensor temperature
A
Condenser sensor temperature
B
Outdoor sensor temperature
Remark
The unit is degree C
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Troubleshooting
6-3-6 Checking EEV
See 6-5 "Fault Diagnosis of Major Parts".
Current EEV step value can monitored with "VIEW MODE"
Press K4 key on the outdoor display PCB for several time to change the display to current EEV value.
Left 1 digit of the LED is data index and Right 3 digits is the value.
Index
Value
3
EEV-A step
4
EEV-B step
5
EEV-C step(For MH068FXEA4 / MH080FXEA4 only)
6
EEV-D step(For MH068FXEA4 / MH080FXEA4 only)
Remark
The step value range is between
zero and 480.
6-3-7 Pipe matching
See 6-2 "Checking and Testing operations".
6-3-8 Checking Motor in indoor unit
See 6-5 "Fault Diagnosis of Major Parts".
Samsung Electronics
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6-4 PCB Inspection
6-4-1 Cautions for Part Replacement
1. The human body carries much static electricity. Before
touching a part for repair, replacement or the similar
purpose, be sure to touch a grounded metallic portion
by hand to let the static electricity go through the
metallic portion to the earth.
Especially when handling any micro computer or IC,
carefully remove such static electricity before touching
them.
2. When repairing any part on a work bench, be sure to
place an insulative sheet on the bench and always keep
the sheet surface neat without any metal fragments.
If any such fragment touches a part, a secondary
trouble will possibly be caused in the part.
3. Before replacing any parts, be sure to turn off the power
supply. If such replacement is done with the power
supply kept on, an electric shock, short circuit or
destruction of a part may result.
4. During replacement or repair of a part, carefully handle
it : The printed circuit board has fine lead wires (jumper
wires) and glass-made parts (diode) on its substrate.
So if a circuit board is roughly handled, such lead wires
and parts will be easily broken or damaged by bending
or shock.
6. When soldering any part, care should be exercised not
to apply any high-wattage soldering iron to the part for a
long time. Some parts are of so low a heat resistance
that they may be broken or have the properties changed
if a soldering iron is so applied (Otherwise, the pattern
may possibly be separated and raised).
7. The heat of the soldering iron should be transferred to
the entire object to be soldered. If the solder pieces are
not well fused due to insufficient transfer of the heat
from the soldering iron, no satisfactory electrical
continuity can be assured even if the soldered objects
appear well connected to each other.
8. The solder used should be limited to a minimum.
If excessive solder is used, it will cause inter-pattern
contact, which may cause malfunction of the circuit.
9. Although some part of the PCB surface are coated with
coating material for protection from dust and dirt,
soldering is also available to the coating part. Because
this coating is thin and is weak for soldering heat.
But coating material remaining on the solder part should
be cleaned up before soldering a new component to
prevent the solder part from becoming bad conduction.
5. When soldering the lead wires of any new part, be sure
to polish them using an emery paper or the like before
soldering them.
Since the lead wires of any new part are covered with
an oxide film, solder cannot adhere to the lead wires if
not polished.
6-4-2 Procedure
The parts should be replaced in the following procedure.
Check for any faulty part.
Detach the faulty part.
Replace it with a new part.
Check the operation of the new part.
The repair is completed.
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6-5 Fault Diagnosis of Major Parts
Preparation : multimeter (AC voltage, DC voltage, Resistance)
Part
Indoor
Temperature sensor
Heat exchanger in/out sensor
Outdoor
Temperature sensor Condenser
temperature sensor
Diagnosis
Measure the resistance between terminals of the sensor connector housing.
In case of outdoor unit sensor, "view mode" is used for checking sensor temperature.
In case of Indoor temperature sensor, temperature is displayed on the display unit in
"Fan Mode" operation.
Normal
Abnormal
Ambient temperature
Resistance of sensor[KΩ]
15˚C
14.7
20˚C
12.1
25˚C
10
30˚C
8.3
25˚C
6.9
40˚C
5.8
∞, 0Ω...open or short
Measure the resistance between terminals of the sensor connector housing.
In case of outdoor unit sensor, "view mode" is used for checking sensor temperature.
Outdoor
Discharge temperature sensor
OLP temperature sensor
Normal
Abnormal
Ambient temperature
0˚C
10˚C
20˚C
30˚C
40˚C
50˚C
Resistance of sensor[KΩ]
553
362
242
166
165
82
∞, 0Ω...open or short
Measure the resistance between terminals of the Motor connector housing
Normal
At the normal temperature (10˚C - 30˚C)
Resistance[Ω]
Terminals(wire color)
Indoor Fan Motor
Yellow-Blue
Yellow-Red
*MH✳✳✳✳✳✳✳ MH035FPEA MH052FPEA
MH19VP2-12
250~280
250~280
120~150
420~480
330~370
120~150
Remark
Main
Sub
*MH020FPEA/MH023FPEA/MH026FPEA /MH18VP2-09/MH19VP2-07
Abnormal
∞, 0Ω...open or short
Measure the resistance between terminals of the Motor connector housing
Normal
Outdoor Fan Motor
Abnormal
Terminals(wire color)
Red-Blue
Yellow-Blue
Blue-White(run capa line)
Red-White Blue(run capa line)
Resistance[Ω]
95~105
95~105
60~75
0~1
Remark
Main 1
Main 2
Sub
Thermal fuse
∞, 0Ω...open or short
Measure the resistance between terminals of the Motor connector housing
Outdoor unit EEV
Stepping motor
Normal
40-50Ω Orange-Gray, Red-Gray, Yellow-Gray, Black-Gray
Abnormal
∞, 0Ω...open or short
Measure the resistance between terminals
Crank case heater
Normal
1.1-1.3KΩ
Abnormal
∞, 0Ω...open or short
Measure the resistance between terminals of the Motor connector housing
Normal
Indoor unit step motor
Flap, Front panel
Abnormal
Samsung Electronics
Motor
Flap
Front panel
Resistance[Ω]
280~320
110~130
Terminals(wire color)
Red-Yellow, Red-Orange,
Red-Blue, Red-Pink
∞, 0Ω...open or short
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