LG Electronics Air Conditioner General Wall Mounted Inverter Type User Manual

Room Air Conditioner  
SVC MANUAL(General)  
MODEL : General Wall Mounted-Inverter Type  
CAUTION  
Before Servicing the unit, read the safety precautions in this SVC manual.  
Only for authorized service personnel.  
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Part 1 General Information  
1. Safety Precautions ............................................................................................................4  
2. Nomenclature......................................................................................................................7  
Service Manual 3  
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Part 1 General Information  
1. Safety Precautions  
To prevent injury to the user or other people and property damage, the following instructions must be followed.  
I Incorrect operation due to ignoring instruction will cause harm or damage. The seriousness is classified by the follow-  
ing indications.  
This symbol indicates the possibility of death or serious injury.  
This symbol indicates the possibility of injury or damage to properties only.  
I Meanings of symbols used in this manual are as shown below.  
Be sure not to do.  
Be sure to follow the instruction.  
Dangerous Voltage  
1.1 Cautions in Repair  
Be sure to disconnect the power cable plug from the plug socket before disas-  
sembling the equipment for a repair.Internal components and circuit boards are at  
main potential when the equipment is connected to the power cables. This high  
voltage is extremely dangerous and may cause death or severe injury if come in  
contact with it.  
Do not touch the discharging refrigerant gas during the repair work.  
The discharging refrigerant gas.The refrigerant gas can cause frostbite.  
Release the refrigerant gas completely at a well-ventilated place first.  
Otherwise, when the pipe is disconnected, refrigerant gas or refrigerating  
machine oil discharges and it Can cause injury.  
When the refrigerant gas leaks during work, perform ventilation. If the refrigerant  
gas comes in contact with a fire, poisonous gas generates. A case of leakage of  
the refrigerant and the closed room full with gas is dangerous because a short-  
age of oxygen occurs. Be sure to perform ventilation.  
When removing the front panel or cabinet, execute short-circuit and discharge  
between high voltage capacitor terminals. If discharge is not executed, an electric  
shock is caused by high voltage resulting in a death or injury.  
Do not turn the air-conditioner ON or OFF by plugging or unplugging the power  
plug. There is risk of fire or electrical shock.  
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Part 1 General Information  
Do not use a defective or underrated circuit breaker. Use the correctly rated  
breaker and fuse. Otherwise there is a risk of fire or electric shock.  
Install the panel and the cover of control box securely. Otherwise there is risk of  
fire or electric shock due to dust, water etc.  
Indoor/outdoor wiring connections must be secured tightly and the cable should  
be routed properly so that there is no force pulling the cable from the connection  
terminals. Improper or loose connections can cause heat generation or fire.  
Do not touch, operate, or repaire the product with wet hands. Holding the plug by  
hand when taking out. Otherwise there is risk of electric shock or fire.  
Do not turn on the breaker when the front panel and cabinet are removed.  
Be sure to ground the air conditioner with an earthing conductor connected to  
the earthing terminal.  
Conduct repair works after checking that the refrigerating cycle section has  
cooled down sufficiently. Otherwise, working on the unit, the hot refrigerating  
cycle section can cause burns.  
Do not tilt the unit while removing panels. Otherwise, the water inside the unit  
can spill and wet floor.  
Do not use the welder in a well-ventilated place. Using the welder in an enclosed  
room can cause oxygen deficiency.  
Be sure to turn off power switch before connecting or disconnecting connector,  
or parts damage may be occur.  
Service Manual 5  
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Part 1 General Information  
1.2 Inspections after Repair  
Check to see if the power cable plug is not dirty or loose. If the plug is dusty or  
loose it can cause an electrical shock or fire.  
Do not use a joined power cable or extension cable, or share the same power  
outlet with other electrical appliances. otherwise, it can cause an electrical shock,  
excessive heat generation or fire.  
Do not insert hands or other objects through the air inlet or outlet while the prod-  
uct is operating. There are sharp and moving parts that could cause personal  
injury.  
Do not block the inlet or outlet of air flow. It may cause product failure  
Check to see if the parts are mounted correctly and wires are connected.  
Improper installation and connections can cause an electric shock or an injury.  
Check whether the installation platform or frame has corroded. Corroded installa-  
tion platform or frame can cause the unit to fall, resulting in injury.  
Be sure to check whether the earth wire is correctly connected.  
After the work has finished, be sure to do an insulation test to check whether the  
resistance is 2[Mohm] or more between the charge section and the non-charge  
metal section (Earth position). If the resistance value is low, a disaster such as a  
leak or electric shock is caused at user’s side.  
Check the drainage of the indoor unit after the repair. If drainage is faulty the  
water may enter the room and wet floor.  
6 Room Air Conditioner  
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Part 1 General Information  
2. Nomenclature  
2.1 Global Model Name  
A S  
2
W 1 2 6 4 G G 1  
10  
1
-
3
4
5
6
7
8
9
Code  
Type  
Code of Model  
Meaning  
L: Chang-won R22  
1
Production Center,  
Refrigerant  
A~Z  
A: Chang-won R410A  
2
3
Product Type  
A~Z  
A~Z  
S: Split Type Air Conditioner  
Cooling/Heating/Inverter  
C: Cooling Only  
H: Heat Pump  
X: C/O + E/Heater  
Z: H/P + E/Heater  
V: AC Inverter C/O  
N: AC Inverter H/P  
Q: DC Inverter C/O  
W: DC Inverter H/P  
4, 5  
6
Capacity  
0~9  
Cooling/Heating Capacity  
Ex. "09" ¡ 9,000 Btu/h  
Electric Range  
1~9  
A~Z  
1: 115V/60Hz  
2: 220V/60Hz  
3: 208-230V/60Hz  
5: 200-220V/50Hz  
6: 220-240V/50Hz  
7: 110V, 50/60Hz  
7
8
Chassis  
Look  
A~Z  
A~Z  
Name of Chassis  
Look,  
Color (Artcool Model)  
9, 10  
Function  
A~Z  
A
B
C
D
E
F
Basic  
Basic+4Way  
Plasma Filter  
Plasma Filter+4 Way  
Tele+LCD  
Tele+LCD+Nano plasma+4Way  
NBF F+(A/changeove)+A/clean+Low A  
NBF F+(A/changeove)+A/clean+4way+Low A  
Tele+LED+4way  
G
H
I
J
Internet  
K
L
Plasma F+4Way+Oxygen generator  
NBF F+(A/changeove)+A/clean  
NBF F+(A/changeove)+A/clean+4way  
NBF F+(A/changeove)+A/clean+PTC  
NBF F+(A/changeove)+Autoclean+4way+PTC  
NBF F+(A/changeove)+A/clean+4way+Low A+PTC  
Negative ion+A/Clean  
M
N
P
Q
R
S
T
U
V
W
Y
(Nano)Plasma+Negative ion+A/Clean  
4way+(Nano)Plasma F+Negative ion+A/Clean  
Nano Plasma F+4Way+(A/changeove)+A/clean+Oxygen generator  
4way+(Nano)Plasma F+Negative ion+A/Clean+Oxygen generator  
Dry contact  
Basic + Low A  
11  
Serial No.  
1~9  
LG Model Development Serial No.  
Service Manual 7  
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Part 2 Functions & Controls  
1. List of Controls & Functions ..........................................................................................9  
2. Basic Mode Controls......................................................................................................10  
3. Special Mode Controls...................................................................................................12  
4. Utility Functions .............................................................................................................13  
5. Protection Functions & Controls .................................................................................16  
8 Room Air Conditioner  
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Part 2 Functions & Controls  
1. List of Functions & Controls  
Category  
Function  
Description  
Remark  
Cooling Mode  
Heating Mode  
Healthy Dehumidification  
Automatic operation  
Auto Changeover  
Cooling operation  
Heating operation  
Dry operation  
Automatic operation  
Cooling mode is automatically changed to heating mode and  
vice verse  
Basic mode  
controls  
Jet Cool  
Jet Heat  
Powerful cooling mode  
Powerful heating mode  
Special Mode  
controls  
Energy saving  
Air volume & set temp. are automatically selected for saving  
energy in cooling mode  
Cooling Mode Only  
Forced operation  
Auto Clean  
Operation without remote controller  
After cooling operation, this function makes the evaporator  
dry  
Air volume control  
Natural Air control  
Chaos Swing  
Indoor Fan speed Control  
Air volume control Program  
Vertical Airflow Direction control  
Utility Functions  
Sleep mode Auto control  
Air volume & set temp. are automatically changed for com-  
fortable sleep  
Auto Restart Function  
When power returns after a power failure, Unit restarts in the  
previous operating mode  
Five Second Delay (Fan)  
For noise prevention  
Two Minutes Stand-by  
(Comp.)  
For overload prevention  
Hot Start  
To prevent cold wind blow on heating mode start  
Evaporator frost prevention  
Condenser frost prevention  
Freeze prevention  
Automatic Defrost  
Power Relay Control  
Over current prevention  
Inverter (with inverter  
power control)  
Overheating Protection  
(Power Module)  
Total Current Control  
(Over Current Protection)  
Modulation of voltage & frequency  
Protection  
Controls &  
Functions  
To protect power module  
To protect power device  
To protect power module  
DC Peak Control  
Discharge Pipe Temp Control For overheating protection  
Low Ambient Function  
Oil Return Control  
Oil Equalizing Control  
For operation at low temp.  
To protect compressor  
To protect compressor  
NOTE: The Exploded View SVC Manual has the particular Function table for each model.  
Service Manual 9  
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Part 2 Functions & Controls  
2. Basic Mode Controls  
2.1 Cooling Mode  
Thermo ON  
Thermo OFF  
+0.5°C(1°F)  
Setting  
Temp.  
-0.5°C(-1°F)  
INV. Comp.  
High  
Low  
Comp. OFF  
High  
Low  
Frequency  
• Operating frequency of compressor depends on the load condition, like the difference between the room temp. and  
the set temp., frequency restrictions.  
• If the compressor operates at some frequency, the operating frequency of compressor cannot be changed within 30  
seconds. ( not emergency conditions)  
• Compressor turned off when  
- intake air temperature is in between 0.5°C( 1°F) of the setting temp. limit for three minutes continuously.  
- intake air temperature reaches below 1.0°C(2°F) of the temperature of setting temp..  
• Compressors two minutes time delay.  
- After compressor off, the compressor can restart minimum 2 minutes later.  
2.2 Heating Mode  
Thermo OFF  
T2°C(T4°F).  
Thermo ON  
T1°C(T2°F).  
Setting  
Temp.  
INV. Comp.  
Frequency  
High  
Low  
Comp. OFF  
High  
Low  
Comp. OFF  
• Operating frequency of compressor depend on the load condition, The difference between the room temp. and set  
temp., frequency restrictions.  
• If compressor operates at some frequency, the operating frequency of compressor cannot be changed within 30 sec-  
onds.  
• Condition of compressor turned off  
- When intake air temperature reaches +T2°C(T4°F) above the setting temperature.  
• Condition of compressor turned on  
- When intake air temperature reaches +T1°C(T2°F) above the setting temperature.  
* Condition of indoor fan turned off  
- While in compressor on : indoor pipe temp. < 20°C(68°F)  
- While in compressor off : indoor pipe temp. < 30°C(86°F)  
• While in defrost control, the indoor and outdoor fans are turned off.  
• Compressor 2minutes delay  
- After compressor off, the compressor can restart minimum 2 minutes later.  
• T1 and T2 may be changed by models  
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Part 2 Functions & Controls  
2.3 Healthy Dehumidification operation  
• When the dehumidification operation is set by the remote controller, the intake air temperature is detected and the set-  
ting temp. is automatically set according to the intake air temperature.  
Intake air Temp.  
26°C(78.8°F) intake air temp.  
Setting Temp.  
25°C(77°F)  
24°C(75.2°F) intake air temp.< 26°C(78.8°F)  
22°C(71.6°F) intake air temp. < 24°C(75.2°F)  
18°C(64.4°F) intake air temp. < 22°C(71.6°F)  
intake air temp. < 18°C(64.4°F)  
intake air temp. -1°C(-2°F)  
intake air temp. -0.5°C(-1°F)  
intake air temp.  
18°C(64.4°F)  
When intake air temp. is 1 C(2 F) above the setting temp., condition of compressor is same as in cooling mode operation.  
• When intake air temperature reaches 1 C(2 F) below the setting temp., compressor operates in step1~step3 and the  
indoor fan speed again operates at low speed or comes to a stop.  
2.4 Automatic operation  
• When the Auto operation is set by the remote controller, the intake air temperature is detected and the setting temp. is  
automatically set according to the intake air temperature and operation mode.  
• The air volume is automatically set according to the intake air temperature.  
2.5 Auto changeover operation  
• The air conditioner changes the operation mode automatically to keep indoor temperature steady.  
• When room temperature vary over 2°C( 4°F) with respect to setting temperature, air conditioner keeps the room tem-  
perature in 2°C( 4°F) with respect to setting temperature by changing the mode from cooling to heating and vice  
versa.  
Switching point  
+4°C(+8°F)  
+2°C(+4°F)  
Heating thermo off  
+0.5°C(+1°F)  
Setting  
Temp.  
Cooling thermo off  
Switching point  
-0.5°C(-1°F)  
-2°C(-4°F)  
Cooling  
operation  
Cooling  
operation  
Mode  
Heating operation  
Service Manual 11  
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Part 2 Functions & Controls  
3. Special Mode Controls  
3.1 Jet Cool operation  
• In the heating mode or Fuzzy operation, the Jet cool function does not work.  
When it is input while in other mode of operation (cooling, dehumidification, ventilation), the Jet cool operation takes  
place.  
• In the Jet cool mode, the indoor fan is operated at super-high speed for 30 min. at cooling mode operation.  
• In the Jet cool mode, the room temperature is maintained at a setting temperature of 18°C(64.4°F).  
• When the sleep timer mode is input during the Jet cool operation, the Jet cool mode has the priority.  
• When the Jet cool button is pressed, the upper/lower vane of the unit is reset to those of the initial cooling mode and  
then operate so that the air outflow could reach further.  
3.2 Jet Heat operation  
• While in cooling mode or Fuzzy operation, the Jet Heat function does not work.  
When it is input while in the Heating mode operation (dehumidification), the Jet Heat mode operation takes place  
• In the Jet Heat mode, the indoor fan operated at super-high speed for 60 min. at Heating mode operation.  
• In the Jet Heat mode, the room temperature is maintained at a temperature of 30°C(86°F).  
• When the sleep timer mode is input during the Jet Heat mode operation, the Jet Heat mode has the priority.  
• When the Jet Heat button is pressed, the upper/lower vane of the unit is the unit reset to those of the initial Jet heating  
mode and then operates so that the air outflow could reach under flow.  
3.3 Energy saving operation in cooling mode  
• During cooling and dehumidification mode of operation, the Energy saving button can be input.  
• In this operation, before we feel cold the set temperature and air volume is set automatically to save energy.  
• The operation time and the other thing was decided by experiment.  
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Part 2 Functions & Controls  
4. Utility Functions  
4.1 Forced operation  
• To operate the appliance manually in case when the remote control is lost, the forced operation selection switch is on  
the main unit of the appliance, and operate the appliance in the standard conditions.  
• The operating condition is set according to the outdoor temp. and intake air temperature as follows.  
Setting speed of  
Operating Mode  
Setting temp.  
Indoor temp.  
indoor fan  
Cooling  
Healthy Dehumidification  
Heating  
22°C(71.6°F)  
23°C(73.4°F)  
24°C(75.2°F)  
over 24°C(75.2°F)  
21~24°C(69.8~75.2°F)  
below 21°C(69.8°F)  
High speed  
• The unit select the last operation mode in 3 hours.  
• Operating procedures when the remote control can't be used is as follows :  
- The operation will be started if the ON/OFF button is pressed.  
- If you want to stop operation, re-press the button.  
- The ON/OFF switch is on the display PCB or side of indoor unit  
4.2 Auto cleaning operation  
• Function used to perform Self Cleaning to prevent the Unit from Fungus and bad odor.  
• Used after the Cooling Operation before turning the unit off, clean the Evaporator and keep it dry for the next opera-  
tion.  
• The function is easy to operate as it is accessed through the Remote controller.  
ON  
Unit  
Operation  
OFF  
ON  
Indoor  
OFF  
Fan  
Setting step  
L Low  
OFF  
ON  
Comp.  
Time  
OFF  
13~14 minutes  
1 minute  
2~3 minutes  
Service Manual 13  
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Part 2 Functions & Controls  
4.3 Air volume control  
• Indoor fan motor control have 6 steps.  
Step  
Description  
LL  
L
Very low, In heating mode  
• Air volume is controlled "SH", "H", "Med", "Low" by the remote con-  
troller.  
Low  
Med  
• "LL" step is selected automatically in Hot start operation.  
M
H
High  
SH  
Auto  
Super high  
Natural wind  
4.4 Natural Air Control(Auto Wind)  
• When the Auto Step is selected and then operated, the high, medi-  
um, or low speed of the airflow mode is operated for 2~15 sec. ran-  
domly by the Chaos Simulation.  
4.5 Chaos Swing  
• By the Chaos swing key input, the upper/lower vane automatically operates with the Chaos swing or it is fixed to the  
desired direction.  
(S4, SE) 9,12kBtu/h Model  
Cooling Operation  
Heating Operation  
CLOSED  
CLOSED  
110°  
110°  
Mode8  
Mode7  
Mode6  
Mode5  
Mode4  
Mode3  
Mode8  
Mode7  
Mode6  
Mode5  
Mode4  
Mode3  
Start  
Start  
Mode2  
Mode1  
Mode2  
Mode1  
8°  
8°  
OPEN  
OPEN  
(S5) 18, 24kBtu/h Model  
Heating Operation  
Cooling Operation  
CLOSED  
CLOSED  
120°  
120°  
Mode9  
Mode8  
Mode7  
Mode6  
Mode5  
Mode4  
Mode9  
Mode8  
Mode7  
Start  
Mode6  
Start Mode5  
Mode4  
Mode3  
Mode2  
Mode1  
OPEN  
8°  
Mode3  
Mode2  
8°  
OPEN  
(SD) 30kBtu/h Model  
Cooling Operation  
Heating Operation  
CLOSED  
CLOSED  
110¡  
110¡  
Mode  
Mode  
Mode  
Mode  
Mode  
8
7
6
5
4
Mode  
Mode  
Mode  
Mode  
Mode  
8
7
6
5
4
Start  
Start  
Mode  
Mode  
Mode  
3
Mode  
Mode  
Mode  
3
2
2
8¡  
8¡  
1
1
OPEN  
OPEN  
NOTE: Some Models are different by swing width and swing pattern.  
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Part 2 Functions & Controls  
4.6 Sleep mode Auto control  
• When the set sleep time is reached set time of [1,2,3,4,5,6,7hour] input by the remote control during the operation, the  
operation of the appliance stops.  
• When the appliance is on pause, the sleep timer mode cannot be input.  
4.6.1 Sleep timer operation for cooling cycle  
• While in cooling mode , 30 min. after the start of the sleep timer, the setting temperature increases by 1 C(2  
.
After another 30minutes lapse, it increases again by 1°C(2  
.
Setting temp. (˚C)  
1.0˚C(2˚F) up  
1.0˚C(2˚F) up  
Cooling ON temp.  
(Setting temp. +0.5˚C(+1˚F))  
Cooling OFF temp.  
(Setting temp. -0.5˚C(-1˚F))  
(
)
0.5  
1
Sleep time hour  
4.6.2 Sleep timer operation for heating cycle  
• While in heating mode, 60 min. after the start of the sleep timer, the setting temperature decreases by 1 C(2  
.
After another 60minutes lapse, it decreases again by 1°C(2  
.
Setting temp. (°C)  
Heating ON temp.  
(Setting temp)  
1.0°C(2°F) down  
1.0°C(2°F) down  
Heating OFF temp.  
(Setting temp. +4.0°C(+8°F))  
(
)
1
2
Sleep time hr  
4.7 Auto restart  
• When the power comes back after a sudden power failure during operation, the mode before the power failure is kept  
on the memory of the appliance and it automatically operates in the saved mode on the memory.  
• Operation mode that is kept on the memory  
- State of operation ON/OFF  
- Operation mode/setting temp./selected airflow speed  
- Sleep timer mode/remaining time of sleep timer  
- Chaos Swing  
Service Manual 15  
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Part 2 Functions & Controls  
5. Protection Functions & Controls  
5.1 Five Seconds Stand-by (fan)  
• The indoor unit fan rotates after 5 seconds when unit is turned on.  
5.2 Two Minutes Stand-by (comp.)  
• Compressor starts two minutes later, after it is turned off  
5.3 Hot start  
• When unit starts in the heating mode to prevent cold wind blowing, the indoor fan does not rotate until the temp. of  
heat exchanger reaches 30°C(86°F)(model by model)  
5.4 Freeze prevention (Protection of the evaporator pipe from frosting)  
• If the indoor pipe temperaure is below 0°C(32°F) in 7 min. after the compressor operates without pause while in cool-  
ing cycle operation mode, compressor, outdoor fan are turned off.  
• When indoor pipe temp. is 7°C(44.6°F) or higher after 2 min pause of compressor compressor, outdoor fan is turned  
on according to the condition of the room temperature.  
Indoor pipe  
temp.  
Comp. free  
Comp. off  
6˚C(42.8˚F)  
7˚C(44.6˚F)  
Comp. Step 4  
Comp. Step 2  
3˚C(37.4˚F)  
T1  
T1: 0 ~ 2°C(32~35.6°F)  
NOTE: Some Models are different by T1.  
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Part 2 Functions & Controls  
5.5 Automatic defrost  
5.5.1 9,12kBtu/h Model  
• While in heating mode operation in order to protect the evaporator pipe of the outdoor unit from freezing,  
reversed to cooling cycle to defrost the evaporator pipe of the outdoor unit.  
• Defrosting control is available 40 minutes later since heating cycle started and the difference of the pipe tem-  
perature of outdoor unit reaches above option 1.  
• The defrosting control is available without reference to heating operation time only if the pipe temperature of  
outdoor unit reaches below option 2.  
The mean outdoor  
temperature  
-10˚C(14˚F) less than -10~-5˚C(14~23˚F) between -5~0˚C(23~32˚F) between 0˚C(32˚F) more than  
Option 1  
>4  
>5  
>5  
>5  
Expected heating operating time  
And Heating operating time 40 minutes  
The minimum Time of  
Heating(sec)  
Option 2  
-30  
-30  
-25  
-25  
Minimum Time  
Of Heating  
Main Deice time  
5sec  
5sec  
30sec 10sec  
1min  
Setting  
Freq.  
Setting Freq.  
Operating  
Freq. Of  
Comp  
Step 5 (Option)_(13)  
Step 3 (Option)_(15)  
Min (Option)_(12)  
Min (Option)_(12)  
(Comp off  
Inapplicable.)  
off  
Operating  
Freq. Of  
Comp  
Setting Freq.  
15sec  
Step 5 (Option)_(13)  
Step 3 (Option)_(15)  
(Comp off  
Applicable.)  
Min (Option)_(12)  
Min (Option)_(12)  
off  
off  
The Degree  
of Superheat  
Control  
300 (Option)_(14)  
Starting Step  
EEV  
Open step  
ON  
ON  
4-Way  
OFF  
Setting  
Speed  
Setting  
Speed  
Indoor  
FAN  
Hi Speed  
Setting  
Speed  
Indoor  
FAN  
Hot  
Start  
Super low speed  
°
low speed  
OFF  
Pre-Heat  
LED  
ON  
OFF  
OFF  
Deice STEP  
0
1
2
3
4
5
6
Service Manual 17  
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Part 2 Functions & Controls  
5.5.2 18,24,30kBtu/h Model  
• Starting to the defrosting operation  
1) Defrost operation will be start when the conditions below are matched  
a) Accumulation time of operation and the period after completion of defrost = 35 min.  
b) After 10 minutes from re-starting the compressor .In case of being over 35 minutes of accumulated operating  
time, defrosting operation starts after 10 minutes.  
c) Piping temperature of the outdoor heat exchanger maintain below defrost starting temperature for 4 minutes  
after 35 minutes continuous operation.  
d)In case of passing 10 minutes after oil recovery operation  
2) Outdoor piping temperature is below than –6°C (21.2°F, Option) for starting defrosting operation.  
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Part 2 Functions & Controls  
• Defrosting Control Algorithm  
1) Lowering the compressor frequency when starts the defrosting operation.  
Constant speed compressor is ON after 10 seconds from the arrival time of 30 Hz (Option) frequency and is  
speed up its revolution till 100 Hz (Option)  
2) Every EEV have 350 pulse (Option) of opening when starts defrosting operation.  
3) Reversing valve is OFF after 5 seconds from arriving the compressor operating frequency of 30 Hz and then  
fans of indoor units turn OFF.(including the indoor unit with being OFF except the remote controller is being  
OFF)  
4) After 5 seconds from the time arriving 30 Hz, fans of outdoor unit turn OFF and Hot Gas bypass/Oil separator  
valve turn ON.  
NOTE: Comp.frequency and EEV pulse is different each models.  
• Control algorithm of defrost completion  
1) Frequency of compressor lowering to 30 Hz and maintain constant speed operation with 30 Hz for 75 seconds  
and then stating operation. If the constant speed compressor is OFF, it will be receive OFF signal after 5 sec-  
onds from the arrival time of 30 Hz.  
2) The EEV will open with the standard previous pulse after 5 seconds from the time of 30 Hz.  
3) Reversing valve is ON after 15 seconds from the time of 30 Hz of compressor frequency.  
4) Fan of outdoor unit is ON with high speed and maintain it after 5 seconds from the time of 30Hz.  
5) Hot Gas bypass valve/Oil separator bypass valve make OFF after 75 seconds from the time of 30Hz.  
NOTE: Comp.frequency and EEV pulse is different each models.  
Service Manual 19  
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Part 2 Functions & Controls  
5.6 Power Relay Control  
• Power relay turns on 1 second later after the power is supplied to the outdoor unit.  
• Control sequence : power on ¡ PTC operating ¡ power relay on  
5.7 Inverter  
U V  
W
+
U
V
3Ø  
Comp.  
Motor  
W
1. The single phase power AC is converted into DC.  
2. The single phase power DC is converted into a three phase chopped DC voltage with a variable frequency.  
3. When the frequency changes, the rotation speed of the compressor changes resulting in an changed refrigerant circu-  
lation. This leads to changeable amount of the heat exchange per unit.  
20 Room Air Conditioner  
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Part 2 Functions & Controls  
5.8 Overheating Protection (Power Module)  
5.8.1 9,12kBtu/h Model  
• If the temperature of the heat sink thermistor. reaches over Toff, the Compressor stop instantly.  
• The compressor operating frequency is limited according to the heat sink thermistor. (refer to below FIG.)  
• It will blink 4 times, when the thermistor is open or short, also when the temperature is over T off.  
T = (T off - T on)/3  
Heat Sink Temp.  
T1 = T on + T  
T2 = T on + 2 T  
*
T off °C  
T2 °C  
T1 °C  
T on °C  
COMP  
Freq.  
Free Fc-1 Fc-2  
Fc-1  
Fc-2  
OFF  
Free  
T on : 85°C(185°F) (Model by Model)  
T off : 95°C(203°F) (Model by Model)  
NOTE: Some Models are different by Ton, and Toff.  
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Part 2 Functions & Controls  
5.8.2 18,24,30kBtu/h Model  
Function  
: Power module failure protection by checking the temperature of heat sink.  
There is a temperature sensor for checking the heat sink temperature.  
Heat sink sensor failure error  
Short Check : if temperature 130°C(266°F)  
Open Check : if temperature < - 30°C(-22°F)  
System will go in self diagnosis (Error code 65) is displayed and product stops.  
Heat sink temperature control  
a) Heat sink temperature < T2  
b) T2 heat sink temperature < Toff : Compressor frequency down by 5 Hz  
c) Heat sink temperature Toff : Compressor will be off.  
: No limitation on compressor frequency  
System will stop if this situation occurs 5 times in 1 hour and error code will be generated also self diagnosis will  
start.  
If high temperature situation occurs 5 times in 1 hr system counts 1 error and after that 4 times if this situation  
occurs system stops and give error code.  
If the temperature reached Toff condition system will count 5 times after that and system will stop with error  
code.  
Heat Sink temp  
Toff=85°C(185°F)  
T2=75°C(167°F)  
T1=70°C(158°F)  
Set  
frequency  
Set  
frequency  
Set  
frequency  
5 Hz  
Down  
5 Hz  
Down  
COMP  
Hz  
OFF  
22 Room Air Conditioner  
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Part 2 Functions & Controls  
5.9 Total Current Control (Over Current Protection)  
5.9.1 9,12kBtu/h Model  
1) CT1 control  
• If the operating current reaches I1, the operating frequency of the compressor decreases.  
• After decreasing the operating frequency by 1step, if operating current is below I1 for 60 seconds continuously, the  
operating frequency of compressor increases by 1step.  
2) CT2 control  
• If the operating current of the appliance reaches I2, the compressor stop instantly and two minutes later the compres-  
sor restarts again.  
• If CT2 occurs 5 times within one hour, the appliance turn off and displays ERROR CODE 7.  
- I1 :Current of operating frequency down(5.5A ~ 12.0A)  
- I2 : Current of compressor cut off(9.0A ~ 14.0A)  
* ( I1, I2 depends on model )  
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Part 2 Functions & Controls  
5.9.2 18,24,30kBtu/h Model  
1) Detection : check the output DC voltage of Current Transformer(CT).  
2) Current Transformer Sensing Error  
a) In initial power input, if the CT output is over 4.0V (25A) it shows.  
Error Code 40 (defect in CT sensing)  
3) CT 1 detection :  
a) If total current exceeds CT1 value.reduce 1 step of operating Hz.  
- Step down 10Hz from current step.  
- If new Hz is below (cooling : Fc min,, heating :Fh min), then turn off the compressor.  
b) After step down,if the total current exceed 1 for more than 5 sec. then step down 1 more step.  
c) If the current continue below 1 for more than 1 min.,return the Hz to setting Hz.  
4) CT 2 detection :  
a) If total current exceeds CT2 turn off compressor.  
And after 3 min turn on the compressor and check the current again.  
b) If CT2 occurs 5 times in 1 hour,stop the operation and shows Error Code 22  
Model  
(kBtu/h)  
Cooling  
(CT 1)  
Heating  
(CT 1)  
CT 2  
18~30  
11A  
12A  
14A  
24 Room Air Conditioner  
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Part 2 Functions & Controls  
5.10 DC Peak control  
5.10.1 DC Peak Current Error by a fault signal of IPM  
• If the operating current of IPM reaches 35A 3A, the compressor stops instantly.  
• If DC PEAK occurs 5 times within 1 hour, the appliance turns off and displays Error Code 6(9,12kBtu/h Model) / Error  
Code 21(18,24,30kBtu/h Model).  
5.10.2 DC Peak Current Error by the compressor lock  
• If the DC LINK voltage below DC 140V occurs 5 times within 1 hour while the compressor is operating, the appliance  
turns off and display Error Code 6(9k,12k Model) / Error Code 23(18k,24k,30k Model).  
5.10.3 DC Peak Current Error by the Outdoor Fan Lock  
• If this problem occurs 5 times within 1 hour in case of the temperature of outdoor pipe TH is over 65°C(149°F) while  
the compressor is operating, the appliance turns off and displays Error Code 6(9,12kBtu/h Model) / Error Code  
61(18,24,30kBtu/h Model).  
5.11 Discharge Pipe Temp Control  
5.11.1 9,12kBtu/h Model  
• If the temperature of the discharge pipe of compressor reaches over 130°C(266°F) or below -30°C(-22°F) the com-  
pressor stops instantly.  
• The compressor operating frequency is limited according to the compressor dome TH. (Refer to below Fig.)  
• Temperature range of COMP SPEC varies by 10°C(50°F).  
T = (T off - T2)/2  
D-Pipe Temp.  
T1 = T2 - 2 T  
*
T off °C  
T3 °C  
T3 = T2 + T  
T2 °C  
T1 °C  
-13 °C(8.6°CF)  
COMP Freq.  
Free  
Fc-1 Fc-2 OFF  
Fc-2 Fc-1 Free  
Fh min  
T off : 110°C(230°F) ( Model by model )  
T2 : 100°C(212°F) ( Model by model )  
NOTE: Some Models are different by T1, and T2.  
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Part 2 Functions & Controls  
5.11.2 Inverter Compressor (18,24,30kBtu/h Model)  
1) There can be two situations  
(a) Sensor is failed (Error Code 41)  
(b) Abnormal high temperature discharge temperature (error code for high discharge will be generated)  
Both cases unit will stop.  
2) Compressor working  
(a) If discharge pipe temperature T1 No limitation on compressor frequency  
(b) T2 discharge pipe temperature T off (Hysteresis control) Compressor frequency down by 5Hz and expan-  
sion valve up by 10 pulse in every 1 min.  
(c) Discharge pipe temperature Toff Compressor will be off  
System will stop if this situation occurs 5 times in 1 hour and error code will be generated.  
D-Pipe temp  
Toff(105)°C(221°F)  
T2(95)°C(203)°F  
T1(90)°C(194)°F  
5 Hz  
Down  
5 Hz  
Down  
COMP  
Hz  
OFF  
Set  
Set  
Set  
Set  
10  
Pulse Up  
10  
Pulse Up  
Expansion  
valve  
Set  
Stop control  
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Part 2 Functions & Controls  
5.11.3 Constant Compressor (only 30kBtu/h Model)  
1) There can be two situations  
(a) Sensor is failed (Error Code 41)  
(b) Abnormal high temperature discharge temperature (error code for high discharge will be generated)  
Both cases unit will stop.  
2) Compressor working  
(a) If discharge pipe temperature < T1 Compressor ON, EEV on-time control  
(b) T2 discharge pipe temperature < Toff (Hysteresis control) Expansion valve up by ßpulse every 1 min.  
If EEV is in the starting control it will follow it as it is.  
(c) Discharge pipe temperature Toff Compressor will be OFF  
System will stop if this situation occurs 5 times in 1 hour and error code will be generated (Error Code 33).  
Toff(105)°C(221)°F  
D-Pipe temp  
T2(95)°C(203)°F  
T1(90)°C(194)°F  
COMP  
ON  
ON  
OFF  
Stop  
Step  
10  
Pulse  
Up  
On-time  
control  
On time  
control  
Expansion  
valve  
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Part 2 Functions & Controls  
5.12 Low Ambient control  
5.12.1 9,12kBtu/h Model  
• If outdoor temperature drops below certain temperature, liquid back is prevented by reducing fan speed.  
• It can prevent frosting of evaporator and keep cooling operation  
• No matter even if the outdoor temperature reaches -10°C(14°F).  
• You can Cool your room at your desired temperature all year around.  
Outdoor temp.:-10°C(14°F)  
25(77°F)  
Comp Freq.  
Cond . temp.  
20(68°F)  
Freq.  
15(59°F)  
Outdoor fan  
10(50°F)  
On  
On  
Outdoor pipe temp.  
Outdoor fan On/Off control  
5(41°F)  
0°C outdoor fan On/Off  
°
control  
Off  
0(32°F)  
Off  
0
50  
100  
150  
Time(Min.)  
200  
Outdoor temp.  
°…  
0°C(32°F)  
-5(23°F)  
5.12.2 18, 24, 30kBtu/h Model  
Low ambient cooling case : In this situation outdoor fan works in ON/OFF control.  
: If the pipe temperature 0°C(32°F) and it is falling rapidly in that case compressor will run for 5 min & then it will  
go in low ambient control. (Temp. value can be different for each model.)  
After the system is stopped by CT cut or heat sink cut-off then the cycle returns to the normal condtiond control.  
Outdoor pipe temp  
(T2 = 0)°C  
(T1 = 0)°C  
O/D fan  
Off  
Off  
Set speed  
Set speed  
Set speed  
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Part 2 Functions & Controls  
5.13 Oil return control(30kBtu/h Model)  
5.13.1 Operating Contion  
1) When the continuous running time is over 3hr.(option), oil returning operation is made for 3min.  
In case of the initial operation, oil returning operation is made, after completing initial operation.  
2) After defrost and oil returning operation, the continuous running time is resetted.  
5.13.2 Operation Process  
1) EEV-Full open, Hot gas bypass valve-On  
2) Compressor Step-70Hz + Constant Comp. On(Option)  
3) Reversing valve-Off(Process of Off/On, follows defrost operating.)  
4) Outdoor Fan-Low step  
5.14 Oil equalizing control(30kBtu/h Model)  
Operating condition :  
1) When the continuous inverter compressor running time at under 40 Hz(option) is over 2 hours(option) in 2 com-  
pressor system, oil restoring operation is made.  
2) If compressor operating Hz is below 40 Hz by the safety control, the accumulated time will be cleared and oil  
restoration is not made.  
3) During this operation,if operating Hz couldn’t be changed by safety control ,stop this operation.  
Operating process : Raise the operating HZ up to 70,and after 20 sec.(option) recover to the last value.  
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Part 3 Test Run  
1. Check before Test Run...................................................................................................31  
2. Test Run Flow chart .......................................................................................................32  
3. Test Run Detail................................................................................................................33  
30 Room Air Conditioner  
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Part 3 Test Run  
1. Check before Test Run  
Check to see whether there is any refrigerant leakage, and check whether the power or transmission  
cable is connected properly.  
1
2
Check whether the liquid pipe and gas pipe valves are fully opened.  
NOTE: Be sure to tighten caps.  
Confirm that 500 V megger shows 2.0 Mor more between power supply terminal block and  
ground. Do not operate in the case of 2.0 Mor less.  
NOTE: Never carry out mega ohm check over terminal control board.  
Otherwise the control board may break.  
3
Immediately after mounting the unit or after leaving it turned off for an extended length of  
time, the resistance of the insulation between the power supply terminal board and the  
ground maydecrease to approx. 2.0 Mas a result of refrigerant accumulation in the internal  
compressor.  
If the insulation resistance is less than 2.0 M, turn on the main power supply.  
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Part 3 Test Run  
2. Test Run Flow chart  
START  
Test operation for indoor unit  
No  
No  
Operate the unit in cooling mode.  
Does Test operation start?  
Refer to part4, 7 Electric part  
Refer to part4, 5 Cycle part  
Yes  
Is cold air discharged for  
more than 3 minutes ?  
Yes  
Is there any temperature  
difference between intake and  
discharged air?  
No  
No  
Yes  
Is the operating current  
normal ?  
* Check the load (In/Out Temp.)  
* Check pipe length and amount of  
refrigerant  
Yes  
* Check for abnormal sound in  
outdoor unit (comp.,Fan, others )  
Operation mode change  
to Heating mode  
No  
Refer to Troubleshooting  
Guide  
Is hot air discharged ?  
After Hot Start  
Yes  
Normal  
NOTE: When outdoor temperature is low,the unit is operated to Heating mode  
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Part 3 Test Run  
3. Test Run Detail  
1. Check that all tubing and wiring have been properly con-  
nected.  
NOTE: If the actual pressure is higher than shown, the  
system is most likely over-charged, and charge  
should be removed.  
2. Check that the gas and liquid side service valves are fully  
open.  
If the actual pressure are lower than shown, the  
system is most likely undercharged, and charge  
should be added.  
Settlement of outdoor unit  
The air conditioner is now ready for use.  
• Anchor the outdoor unit with a bolt and nut(ø10mm) tightly  
and horizontally on a concrete or rigid mount.  
PUMP DOWN  
• When installing on the wall, roof or rooftop, anchor the  
mounting base securely with a nail or wire assuming the  
influence of wind and earthquake.  
This is performed when the unit is to be relocated or  
the refrigerant circuit is serviced.  
Pump Down means collecting all refrigerant in the outdoor  
unit without loss in refrigerant gas.  
• In the case when the vibration of the unit is conveyed to the  
hose, secure the unit with an anti-vibration bushing.  
CAUTION:  
Be sure to perform Pump Down procedure with the unit in  
Bolt  
cooling mode.  
Pump Down Procedure  
1. Connect a low-pressure gauge manifold hose to the  
charge port on the gas side service valve.  
2. Open the gas side service valve halfway and purge the air  
from the manifold hose using the refrigerant gas.  
Tubing connection  
3. Close the liquid side service valve(all the way in).  
Evaluation of the performance  
4. Turn on the unit's operating switch and start the cooling  
operation.  
Operate unit for 15~20 minutes, then check the system  
refrigerant charge:  
5. When the low-pressure gauge reading becomes 1 to  
0.5kg/cm2 G(14.2 to 7.1 P.S.I.G.), fully close the gas side  
valve stem and then quickly turn off the unit. At that time,  
Pump Down has been completed and all refrigerant gas  
will have been collected in the outdoor unit.  
1. Measure the pressure of the gas side service valve.  
2. Measure the temperature of the intake and discharge air.  
3. Ensure the difference between the intake temperature and  
the discharge is more than 8°C(46°F) (Cooling) or  
(Heating).  
5. Check operating current.  
Intake temperature  
Discharge air  
6. Change operation mode and check.  
Discharge  
temperature  
4. For reference; the gas side pressure of optimum condition  
is as below.(Cooling)  
Outside ambient  
TEMP.  
The pressure of the gas side  
service valve.  
Refrigerant  
R22  
R410A  
35°C (95°F)  
35°C (95°F)  
4~5kg/cm2G(56.8~71.0 P.S.I.G.)  
8.5~9.5kg/cm2G(120~135 P.S.I.G.)  
Service Manual 33  
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Part 4 Trouble Shooting  
1. 2-Way, 3-Way Valve ........................................................................................................35  
2. Pumping Down ..............................................................................................................36  
3. Evacuation (All amount of refrigerant leaked) ............................................................37  
4. Gas Charging (After Evacuation) .................................................................................38  
5. Self-diagnosis Function.................................................................................................39  
6. Cycle Troubleshooting Guide........................................................................................42  
7. Electronic Parts Troubleshooting Guide......................................................................44  
34 Room Air Conditioner  
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Part 4 Trouble Shooting  
1. 2-Way, 3-Way Valve  
2-way Valve (Liquid Side)  
3-way Valve (Gas Side)  
Valve cap  
Hexagonal wrench (4mm)  
Open position  
Closed position  
Flare nut  
Flare nut  
Open position  
Closed position  
Pin  
To  
To  
piping  
piping  
connection  
Service  
port cap  
Service  
port  
connection  
To outdoor unit  
To outdoor unit  
Works  
Shaft position  
Shaft position  
Service port  
Closed  
(with valve cap)  
Closed  
(with valve cap)  
Closed  
(with cap)  
Shipping  
Air purging  
Open  
Closed  
Open  
1.  
(Installation)  
(counter-clockwise)  
(clockwise)  
(push-pin or with  
vacumm pump)  
Open  
(with valve cap)  
Open  
(with valve cap)  
Closed  
(with cap)  
Operation  
Closed  
(clockwise)  
Open  
Open  
Pumping down  
(Transfering)  
(counter-clockwise) (connected manifold  
gauge)  
2.  
3.  
4.  
Open  
Open  
Open  
Open  
Open  
(with charging  
cylinder)  
Evacuation  
(Servicing)  
Open  
(with charging  
cylinder)  
Gas charging  
(Servicing)  
Open  
Pressure check  
(Servicing)  
(with charging cylinder)  
Open  
Open  
Open  
Open  
5.  
6.  
Open  
Gas releasing  
(Servicing)  
(with charging cylinder)  
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Part 4 Trouble Shooting  
2. Pumping Down  
Liquid side  
2-Way  
Indoor unit  
Outdoor unit  
Open  
valve  
Gas side  
Closed  
3-Way  
valve  
Lo  
CLOSE  
CLOSE  
Purge the air  
Procedure  
(6) Operate the air conditioner at the cooling  
(1) Confirm that both the 2-way and 3-way valves  
are set to the open position.  
cycle and stop it when the gauge indicates  
2
.
1kg/cm g.  
– Remove the valve stem caps and confirm that  
the valve stems are in the raised position.  
– Be sure to use a hexagonal wrench to operate  
the valve stems.  
(7) Immediately set the 3-way valve to the closed  
position.  
– Do this quickly so that the gauge ends up indi-  
2
.
cating 3 to 5kg/cm g.  
(2) Operate the unit for 10 to 15 minutes.  
(8) Disconnect the charge set, and mount the 2-  
way and 3-way valves stem nuts and the ser-  
vice port nut.  
(3) Stop operation and wait for 3 minutes, then  
connect the charge set to the service port of  
the 3-way valve.  
– Use torque wrench to tighten the service port  
– Connect the charge hose with the push pin to  
the service port.  
.
nut to a torque of 1.8 kg m.  
– Be sure to check for gas leakage.  
(4) Air purging of the charge hose.  
– Open the low-pressure valve on the charge set  
slightly to air purge from the charge hose.  
(5) Set the 2-way valve to the closed position.  
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Part 4 Trouble Shooting  
3. Evacuation (All amount of refrigerant leaked)  
Liquid side  
Indoor unit  
Outdoor unit  
3-Way  
valve  
Open  
Gas side  
3-Way  
valve  
Open  
Vacuum pump  
Vacuum  
Gage  
Lo  
OPEN  
OPEN  
Procedure  
(1) Connect the vacuum pump to the center hose  
of charge set center hose  
(3) Close the valve (Lo side) on the charge set,  
turn off the vacuum pump, and confirm that  
the gauge needle does not move (approxima-  
tely 5 minutes after turning off the vacuum  
pump).  
(2) Evacuation for approximately one hour.  
– Confirm that the gauge needle has moved  
toward 0.8 Torr.  
(4) Disconnect the charge hose from the vacuum  
pump.  
– Vacuum pump oil.  
If the vacuum pump oil becomes dirty or  
depleted, replenish as needed.  
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Part 4 Trouble Shooting  
4. Gas Charging (After Evacuation)  
Liquid side  
Indoor unit  
Outdoor unit  
Open  
3-Way  
valve  
Gas side  
Open  
3-Way  
valve  
Check valve  
OPEN  
Charging  
cylinder  
Vacuum  
Gage  
Lo  
(1)  
CLOSE  
Procedure  
This is different from previous procedures.  
Because you are charging with liquid refrigerant  
from the gas side, absolutely do not attempt to  
charge with larger amounts of liquid refrigerant  
while operating the air conditioner.  
(1) Connect the charge hose to the charging  
cylinder.  
– Connect the charge hose which you dis-con-  
nected from the vacuum pump to the valve at  
the bottom of the cylinder.  
– If you are using a gas cylinder, also use a  
scale and reverse the cylinder so that the sys-  
tem can be charged with liquid.  
(4) Immediately disconnect the charge hose from  
the 3-way valves service port.  
(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 refriger-  
ant). The procedure is the same if using a gas  
cylinder.  
– Stopping partway will allow the gas to be dis-  
charged.  
– If the system has been charged with liquid  
refrigerant while operating the air conditioner  
turn off the air conditioner before disconnecting  
the hose.  
(3) Open the valve (Lo side on the charge set and  
charge the system with liquid refrigerant.  
– If the system can not be charged with the spec-  
ified amount of refrigerant, it can be charged  
with a little at a time (approximately 150g each  
time) while operating the air conditioner in the  
cooling cycle; however, one time is not suffi-  
cient, wait approximately 1 minute and then  
repeat the procedure (pumping down-pin).  
(5) Mount the valve stem nuts and the service  
port nut.  
– Use torque wrench to tighten the service port  
nut to a torque of 1.8 kg.m.  
– Be sure to check for gas leakage.  
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Part 4 Trouble Shooting  
5. Cycle Troubleshooting Guide  
Trouble analysis  
1. Check temperature difference between intake and discharge air, and operating current.  
Temp. difference  
Current  
: approx. 0°C(1°F)  
: less than 80% of  
rated current  
All amount of refrigerant leaked out.  
Check refrigeration cycle.  
Temp. Difference  
Operating Current  
Refrigerant leakage  
Clog of refrigeration cycle  
Defective compressor  
Temp. difference  
Current  
: approx. 8°C(16°F)  
: less than 80% of  
rated current  
Temp. difference  
Current  
: less than 8°C(16°F)  
: near the rated  
current  
Excessive amount of refrigerant  
Temp. difference : over 8°C(16°F)  
Normal  
NOTICE  
Temperature difference between intake and discharge air depends on room air humidity. When the room air  
humidity is relatively higher, temperature difference is smaller. When the room air humidity is relatively lower  
temperature difference is larger.  
Service Manual 39  
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Part 4 Trouble Shooting  
2. Check temperature and pressure of refrigeration cycle.  
Suction pressure  
(Compared with  
the normal value)  
Temperature  
(Compared with  
the normal value)  
Cause of Trouble  
Description  
High  
Defective compressor  
Current is low.  
Higher  
Lower  
Normal  
Excessive amount of  
refrigerant  
High pressure does not quickly  
rise at the beginning of operation.  
Insufficient amount of  
refrigerant(Leakage)  
Clogging  
Current is low.  
Higher  
NOTICE  
2
.
1. The suction pressure is usually 8.5~9.5 kg/cm g at normal condition.  
2. The temperature can be measured by attaching the thermometer to the low pressure tubing and wrap it with  
putty.  
40 Room Air Conditioner  
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Part 4 Trouble Shooting  
6. Electronic Parts Troubleshooting Guide  
The Product doesnt operate at all. (9~30kBtu/h Model)  
Trouble 1  
Turn off the main power and wait until LED on outdoor PCB is off.  
Turn on the main power again.  
Does "Beeping" sound is made from the indoor unit?  
Does "Lighting" LED is mounted on the outdoor PCB?  
NO  
YES  
• Primarily, the operating condi-  
tion of Micom is O.K.  
Check the voltage of power(AC 208~230V, 60Hz).  
• The voltage of main power.  
• The voltage applied to the unit.  
• The connecting method of Indoor/Outdoor connecting cable (each color)  
• The P.W.B. Ass'y  
(Fuse,Noise Filter, Power Module(SMPS), IC01D,IC04D)  
• Check CN-DISP1  
The operation check of the P.C.B. Ass'y  
Specification  
: DC 220V~390V  
Remedy  
Procedure  
1) The input voltage of Power  
Module(SMPS)  
Replace the P.C.B.  
2) The output voltage of Power  
Module (SMPS)  
: 15V 10%  
: DC 5V  
3) IC01D(LD1085), IC04D(7805)  
Service Manual 41  
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Part 4 Trouble Shooting  
Product doesn't operate with the remote controller. (9~30kBtu/h Model)  
Trouble 2  
Turn on main power.  
While the compressor has been stopped, the compressor does not operate  
owing to the delaying function for 2 minutes after stopped.  
When the compressor stopped Indoor Fan is driven by a low speed.  
At this point the wind speed is not controlled by the remote controller.  
(When operated in the Sleeping Mode, the wind speed is set to the low speed as force).)  
Caused by other parts except  
Caused by the remote controller.  
the remote controller  
When the mark (  
) is displayed in LCD  
Check the contact of CN-DISP 1, 2 connector  
screen, replace battery.  
Check DISP P.C.B Ass'y  
-Voltage between CN-DISP1  
-
: DC +5V  
Check point  
• Check the connecting circuit between  
MICOM PIN and CN-DISP1 PIN  
• Check receiver ass'y  
42 Room Air Conditioner  
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Part 4 Trouble Shooting  
The Compressor/Outdoor Fan don't operate (9~30kBtu/h Model)  
Trouble 3  
Turn on the main power.  
Operate Cooling Mode by setting the disired temperature of the remote controller is less  
than one of the Indoor temperature by 1°C at least.  
When in air circulation mode, compressor/outdoor fan is stopped.  
Check the sensor for Indoor temperature is attatched as close as to be effected by the  
themperature of Heat Exchange (EVA.)  
When displaying Error code, refer to the trouble shooting guide.  
Check the main power source.(AC 208V~230V)  
Check the trouble shooting guide error code 6,9  
Turn off main power.  
Check the electrical wiring diagram of Outdoor side.  
Check the open or short of connecting wires between Indoor and Outdoor.  
Service Manual 43  
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Part 4 Trouble Shooting  
The Compressor/Outdoor Fan don't operate (18, 24, 30kBtu/h Model)  
Trouble 4  
Turn on the main power.  
Operate Cooling Mode by setting the disired temperature of the remote controller is less  
than one of the Indoor temperature by 1°C at least.  
When in air circulation mode, compressor/outdoor fan is stopped.  
Check the sensor for Indoor temperature is attatched as close as to be effected by the  
themperature of Heat Exchange (EVA.)  
When displaying Error code, refer to the trouble shooting guide.  
Check the main power source.(AC 208V~230V)  
Check the trouble shooting guide error code 21,26.  
Check that CN_FAN(A,B) supplied voltage to outdoor PCB is about AC 208V~230V.  
Turn off main power.  
Check the electrical wiring diagram of Outdoor side.  
Check the open or short of connecting wires between Indoor and Outdoor.  
44 Room Air Conditioner  
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Part 4 Trouble Shooting  
When indoor Fan does not operate.(9~30kBtu/h Model)  
Trouble 5  
Turn off main power.  
Check the connection of CN-FAN.  
Check the Fan Motor.  
Check the Fuse(AC250V, T2A).  
Check the related circuit of indoor Fan Motor.  
• The pin No. 38 of micom and the part for driving SSR.(Q01M)  
• Check the related pattern.  
• Check the SSR.  
- SSR Open: Indoor Fan Motor never operate.  
- SSR short: Indoor Fan Motor always operates in case of ON or OFF.  
Turn on the main power  
Check the SSR high speed operation by remote control.  
(the Indoor Fan Motor is connected)  
The voltage of Pin No 1(orange) and 3(black) of CN-FAN.  
About AC 160V over  
SSR is not damaged  
About AC 50V over  
Check SSR  
Service Manual 45  
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Part 4 Trouble Shooting  
7. Self-diagnosis Function  
I Error Indicator  
• The function is to self-diagnoisis airconditioner and express the troubles identifically if there is any trouble.  
• Error mark is ON/OFF for the operation LED of evaporator body in the same manner as the following table.  
• If more than two troubles occur simultaneously, primarily the highest trouble fo error code is expressed.  
• After error occurrence, if error is released, error LED is also released simultaneously.  
• To operate again on the occurrence of error code, be sure to turn off the power and then turn on.  
• Having or not of error code is different from Model.  
I 9, 12kBtu/h Model  
Indoor  
Operation  
Display  
Indoor Outdoor  
Error  
Code  
Cause of Error  
Error Indicator  
1 time  
3 sec  
1time  
3 sec  
2times  
3 sec  
4times  
1time  
1time  
3 sec  
1time  
Indoor Temp. sensor error  
- Sensor open or short  
O
1
2
ON  
ON  
3 sec  
2times  
2times  
3 sec  
2times  
3 sec  
Outdoor Temp. sensor error  
- Sensor open or short  
O
O
O
O
O
O
O
O
4times  
3 sec  
5times  
3 sec  
Heat Sink sensor error  
- Sensor open or short  
- Heat Sink temp is over 9°5  
ON  
4
5
6
3 sec  
5times  
3 sec  
Communication error  
OFF  
6times  
3 sec  
6times  
SHUT  
DOWN  
DC Peak error  
7times  
8times  
9times  
7times  
3 sec  
SHUT  
DOWN  
O
O
O
O
Over current error (CT2)  
7
8
8times  
3 sec  
Indoor fan lock error  
(BLDC fan model only)  
OFF  
OFF  
9times  
3 sec  
Outdoor fan lock error  
(BLDC fan model only)  
O
O
9
10times 10times  
3 sec  
D-Pipe TH. is short or open.  
O
ON  
10  
(4 LED Model)  
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Part 4 Trouble Shooting  
I 18,24,30kBtu/h Model  
Indoor Error  
LED1  
(Red)  
LED2  
(Green)  
Indoor  
Status  
ON  
Error code  
Descrition  
INV TPS  
00  
01  
02  
03  
04  
05  
06  
07  
No Error  
Indoor Room themistor error  
Indoor in-piping sensor error  
Remote controler error  
1time  
2times  
3times  
4times  
5times  
6times  
times  
OFF  
OFF  
OFF  
OFF  
OFF  
OFF  
OFF  
Drain Pump error  
Communcation error between in and out  
Indoor Out-Piping sensor error  
Diffrent mode operation  
Outdoor Error  
Ex) Error Code 21 (IPM Fault)  
2 Times  
2 Times  
1 Sec.  
2 Times  
1 Sec.  
LED01G  
(RED)  
1 Sec.  
1 Time  
1 Time  
1 Time  
LED02G  
(GREEN)  
2 Sec.  
2 Sec.  
LED02G  
(Green)  
Outdoor  
Status  
Error  
code  
LED01G  
(Red)  
Contents  
Case of error  
21  
IPM Fault (Compressor Over current)  
CT 2(Max. Current)  
2 times  
2 times  
2 times  
2 times  
2 times  
2 times  
2 times  
2 times  
3 times  
3 times  
1 time  
Compressor malfunction,IPM Fault  
Current is 14A  
Off  
Off  
Off  
Off  
Off  
Off  
Off  
Off  
Off  
Off  
22  
2 times  
3 times  
4 times  
5 times  
6 times  
7 times  
8 times  
2 times  
3 times  
23  
DC Link Low Volt.  
DC Link volt. Is 140V  
24  
Low / High press  
Low / High press switch OPEN  
Abnormal AC volt. Input.  
25  
AC Low / AC High Volt.  
DC Compressor Position  
PSC Fault  
26  
27  
28  
DC Link High Volt  
Off  
Off  
Off  
32  
Discharge Pipe Temp. High (INV)  
Discharge Pipe Temp. High (Cons.)  
33  
Service Manual 47  
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Part 4 Trouble Shooting  
LED02G  
(Green)  
Outdoor  
Status  
Error  
code  
LED01G  
(Red)  
Contents  
Case of error  
40  
CT Circuit (open/ short)  
4 times  
4 times  
4 times  
4 times  
4 times  
4 times  
5 times  
5 times  
6 times  
6 times  
6 times  
6 times  
CT Circuit malfunction  
Open / Short  
Off  
Off  
Off  
Off  
Off  
Off  
Off  
Off  
Off  
Off  
Off  
Off  
41  
D-pipe sensor INV. (open/ short)  
Air sensor (open/ short)  
1 time  
44  
4 times  
5 times  
6 times  
7 times  
1 time  
Open / Short  
45  
Cond. Pipe sensor (open/ short)  
Suction pipe sensor (open/ short)  
D-pipe sensor Cons. (open/ short)  
Over capacity  
Open / Short  
46  
Open / Short  
47  
Open / Short  
51  
Over load combination  
Communication Poorly  
Check sum mismatching  
Cond. Temp. high  
Heat sink temp. high  
Open / Short  
53  
Communication (Indoor Outdoor)  
EEPROM check sum  
3 times  
60  
61  
Cond. Pipe sensor temp. high  
Heat sink sensor temp. high  
Heat sink sensor (open/ short)  
1 time  
62  
2 times  
5 times  
65  
48 Room Air Conditioner  
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Part 4 Trouble Shooting  
I Troubleshooting Guide(9,12kBtu/h Model)  
Error code  
Description  
Cause of error  
Indoor TH. (sensor) is short or open  
Indoor TH. is short or  
open  
Indoor TH. (sensor) is not connected to the indoorpcb assembly  
Damage or defect on the sensing circuit of indoorpcb assembly.  
(R01H, R02H, R03H, R04H, C01H, C02H)  
1
Check flow  
YES  
YES  
Indoor TH. is connected to  
Indoor pcb assembly ?  
Sensing circuit of indoor  
pcb is right ?  
Indoor TH. is right ?  
No  
No  
No  
Check Indoor TH.  
- Connect to CN-TH1 in  
indoor pcb assembly  
- Measure resistance of TH.  
(air : about 10kat 25°C(77°F),  
pipe : about 5kat 25°C(77°F)  
- Check soldering state of  
R01H ~ R04H, C01H, C02H  
Error code  
Description  
Cause of error  
Outdoor TH. (sensor) is short or open  
Outdoor TH. is short or  
open  
Outdoor TH. (sensor) is not connected to the outdoorpcb assembly  
Damage or defect on the sensing circuit of outdoorpcb assembly.  
(R03H~R06H, C02H, C03H)  
2
Check flow  
YES  
YES  
Outdoor TH. is connected to  
outdoor pcb assembly ?  
Sensing circuit of outdoor  
Outdoor TH. is right ?  
pcb is right ?  
No  
No  
No  
Check outdoor TH.  
- Connect to CN-TH1 in  
outdoor pcb assembly  
- Measure resistance of TH.  
- Check soldering state of  
R03H ~ R06H, C02H, C03H  
(air : about 10kat 25°C(77°F),  
pipe : about 5kat 25°C(77°F)  
Service Manual 49  
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Part 4 Trouble Shooting  
Error code  
Description  
Cause of error  
Heat-sink TH. is damaged(short or open).  
Heat-sink Temp. is over  
95°C(203°F)  
Heat-sink TH.  
is open or short  
Heat-sink Temp. is over 95°C(203°F)  
4
Damage or defect on the sensing circuit of outdoorpcb assembly.  
(R01H, R02H, C01H)  
Check flow  
YES  
YES  
Heat-sink TH is connected to  
outdoor PCB assembly?  
Heat-sink TH. in INV-IC is  
Right ?  
Sensing circuit of outdoor  
pcb is right ?  
No  
No  
No  
Check heat-sink TH.  
- Measure resistance of TH.  
(about 10kat 25°C(77°F))  
- Check soldering state of  
R01H, R02H, C01H  
- Connect to CN-TH2 in  
outdoor PCB assembly  
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Part 4 Trouble Shooting  
Cause of error  
Error code  
Description  
Wrong or missing wiring between indoor and outdoor unit cable  
Defect of communication components in indoorpcb assembly  
Defect of communication components in outdoorpcb assembly  
Defect of power supply components in outdoorpcb assembly  
No ground connection in air conditioner unit  
Communication Error  
5
(affected by noise in power source)  
Check flow  
YES  
YES  
Is the voltage of T/Block  
in outdoor about  
AC 208~230V ?  
Wiring connection  
Is right ?  
Is the voltage of GND & DC5V in  
Outdoor pcb about DC 5V ?  
,
No  
No  
No  
Indoor  
1(BR)  
2(BL)  
Outdoor  
1(BR)  
2(BL)  
Check power connector  
Is not connected to the  
T/Block in indoor unit.  
Check FUSE, NF01/02J, PTC,  
Power Module, BD-01S in  
Outdoor pcb assembly  
3(GN/YL) 3(GN/YL)  
4(RD)  
4(RD)  
YES  
YES  
Communication circuit of indoor  
& outdoor pcb Is right ?  
Ground connection is installed ?  
(power outlet or outdoor chassis)  
No  
No  
Earth port  
Check IC01K, IC02K,D01K~D03K,  
ZD01K~ZD03K, R01K~R10K,  
C01K~C04K  
Install ground connection from outdoor  
unit. (In case power outlet has no earth  
port)  
Service Manual 51  
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Part 4 Trouble Shooting  
Error code  
Description  
Cause of error  
Supplied power is not normal  
Comp Connector (CN-U,V,W) is disconnected or inserted to wrong  
position  
DC Peak Error  
6
Compressor is damaged (coil short) replace compressor  
Too much Refrigerant  
Defect in outdoor pcb assembly replace pcb assembly  
Check flow  
YES  
YES  
Supplied voltage to  
Outdoor pcb is about  
AC 208~230V ?  
Is connector (CN-U,V,W)  
connected to compressor and  
inserted to pcb in right position ?  
Refrigerant pressure is right ?  
No  
No  
No  
Check CN-U,V,W connector  
(U : RD, V : BL, W : YL)  
Check refrigerant pressure  
and adjust.  
Check power source  
YES  
YES  
Inverter components in outdoor pcb assembly are  
right ?  
Is the compressor right ?  
No  
No  
Check resistance  
* 9 K/12K Model  
Between U-V, V-W, U-W port.  
¡Short / Open circuit  
(Comp.motor coil error)  
¡normal : 1 ~2Ω  
Between U,V,W and Body  
¡normal : over 10MΩ  
Check  
Short of SPM3 pins (GND - P, U, V, W pin)  
Direction of D01Z~D03Z, C08Z,10Z,12Z,16Z  
Assembling state of R01P ~ R21P & IC01P  
Assembling state of screw between INV-IC &  
Heat-sink  
DC 15V output of Power module.  
U
W
V
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Part 4 Trouble Shooting  
Cause of error  
Error code  
Description  
Supplied power is not normal  
Indoor/outdoor fan is locked  
Too much refrigerant  
Defect in current sensing circuit in outdoor pcb assembly  
Over current Error  
(CT2)  
7
Check flow  
YES  
YES  
Supplied voltage to  
Outdoor pcb is about  
AC 208~230V ?  
Does indoor / outdoor fan work  
normally ?  
Refrigerant pressure is right ?  
No  
No  
No  
Check indoor / outdoor fan and  
adjust.  
Check refrigerant pressure  
and adjust.  
Check power source  
YES  
Current sensing circuit is right ?  
No  
Check current sensing circuit.  
- check CT is damaged in outdoor pcb  
(output wire is disconnected to pin or not)  
- BD01N is inserted in right position  
(refer marking on pcb and component)  
- Spec of R01N (1k), R02N (1.65k) is correct  
- Direction of diode (D01N, D02N) is right  
Service Manual 53  
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Part 4 Trouble Shooting  
Error code  
Description  
Cause of error  
Indoor fan is locked or separated  
Fan connector is not connected to indoor pcb assembly  
Defective in DC-fan driving circuit  
Indoor fan is locked  
8
(BLDC fan model only)  
Check flow  
YES  
YES  
Indoor fan is rotating ? (1)  
No  
Indoor fan is rotating ? (2)  
DCfan driving circuit is right ?  
No  
No  
Check indoor unit  
- remove obstacles in  
indoor unit  
Check DC Fan Driving circuit  
(Soldering state & Direction)  
- R01F~R09F, C01F~C03F,  
IC01F~IC03F, Q01F~Q02F, ZD01F  
Check soldering state of  
CN-Motor1 & assembling  
state of DC Fan connector  
- fan assembled correctly.  
Error code  
Description  
Cause of error  
Outdoor fan is locked by an obstacle (ex : branch of tree, baretc)  
Fan connector is not connected to outdoor pcb assembly  
Defective in DC-fan driving circuit  
Outdoor fan is locked  
(BLDC fan model only)  
9
Check flow  
YES  
YES  
Outdoor fan is rotating ? (1)  
No  
Outdoor fan is rotating ? (2)  
No  
DCfan driving circuit is right ?  
No  
Check DC Fan driving circuit  
(Soldering state & Direction)  
- R01F~R05F, C01F~C03F,  
Q01F~Q04F, ZD01F  
Check outdoor unit  
- remove obstacles in  
outdoor unit  
Check connector is not  
connected to outdoor pcb  
assembly (CN-FAN2)  
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Part 4 Trouble Shooting  
Cause of error  
Error code  
Description  
D_pipe TH. is short or open  
D_pipe TH. is not connected to the outdoor pcb assembly  
Damage or defect on the sensing circuit of outdoor pcb assembly  
D-Pipe TH. is short or  
open  
10  
Check flow  
YES  
YES  
D_PIPE TH. is connected to  
Outdoor pcb assembly ?  
Sensing circuit of outdoor  
D_PIPE TH. is right ?  
pcb is right ?  
No  
No  
No  
Check D_PIPE TH.  
- Measure resistance of TH.  
(about 200kat 25°C(77°F)).  
Connect to CN-D_PIPE  
in outdoor pcb assembly  
- Check soldering state of  
R07H, R08H, C04H  
Service Manual 55  
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Part 4 Trouble Shooting  
I Troubleshooting Guide(18,24,30kBtu/h Model)  
1) Troubleshooting CH01, CH02, CH06  
Error  
code  
Title  
Cause of error  
• Open / Short  
• Soldered poorly  
• Internal circuit error  
Check point & Normal condition  
Normal resistor : 10k/ at 25°C(77°F) (Unplugged)  
Normal voltage : 2.5VDC / at 25°C(77°F) (plugged)  
Indoor air sensor  
01  
• Open / Short  
• Soldered poorly  
• Internal circuit error  
Normal resistor : 5k/ at 25°C(77°F) (Unplugged)  
Normal voltage : 2.5VDC / at 25°C(77°F) (plugged)  
Indoor inlet pipe sensor  
Indoor outlet pipe sensor  
02  
06  
• Open / Short  
• Soldered poorly  
• Internal circuit error  
Normal resistor : 5k/ at 25°C(77°F) (Unplugged)  
Normal voltage : 2.5VDC / at 25°C(77°F) (plugged)  
10k  
2.5VDC  
V
Check the resistance  
Check the voltage  
Check Point  
1. Unplug the sensor on Indoor unit PCB.  
2. Estimate the resistance of each sensor.  
3. If the resistance of the sensor is 10k/ 5kat 25°C(77°F), then sensor is normal.  
4. If the resistance of the sensor is 0 kor , then sensor is abnormal. ¡ Change the sensor.  
5. Plug the sensor on Indoor unit PCB and Power ON.  
6. Estimate the voltage of each sensor.  
7. If the voltage of the sensor is 2.5VDC at 25°C(77°F), then sensor is normal.  
8. If the resistance of the sensor is 0 or 5VDC, then sensor is abnormal. ¡ Repair or Change the PCB.  
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Part 4 Trouble Shooting  
2) Troubleshooting CH05, CH53  
Error  
Title  
Cause of error  
Check point & Normal condition  
code  
• Power input AC 208~230V. (Outdoor, Indoor)  
• The connector for transmission is disconnected.  
• The connecting wires are misconnected.  
• The GND1,2 is not connected at main GND.  
• The communication line is shorted at GND.  
• Transmission circuit of outdoor PCB is abnormal.  
• Transmission circuit of indoor PCB is abnormal.  
05  
/
53  
Communication  
(Indoor ¡ Outdoor)  
• Communication poorly  
Check Point  
1. Check the input power AC 208~230V. (Outdoor, Indoor unit)  
2. Check the communication wires are correctly connected.  
¡ Adjust the connection of wire  
¡ Confirm the wire of “Live”, “Neutral”  
3. Check the resistance between communication line and  
GND. (Normal : Over 2M)  
4. Check the connector for communication is correctly  
connected.  
5. Check the connection of GND1, GND2, and main GND.  
6. If one indoor unit is operated normally, outdoor PCB is no  
problem.  
¡ Check the another indoor unit.  
* CH05 is displayed at indoor unit, CH53 is displayed at out-  
door unit.  
Service Manual 57  
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Part 4 Trouble Shooting  
3) Troubleshooting CH21  
Error  
Title  
Cause of error  
Check point & Normal condition  
code  
• An instant over current in the U,V,W phase  
- Comp lock  
- The abnormal connection of U,V,W  
• Over load condition  
- Overcharging of refrigerant  
- Pipe length.  
• Instant over current  
• Over Rated current  
• Poor insulation of IPM  
21  
DC Peak  
• Poor insulation of compressor  
Comp  
Resistance() at 20°C(68°F)  
U
Constant  
comp.  
Inverter  
comp.  
Terminal  
U-V  
V-W  
W-U  
0.64  
0.64  
0.64  
0.8  
0.8  
0.8  
V
W
Copper  
pipe  
Comp  
Resistance() at 20°C(68°F)  
Constant  
comp.  
Inverter  
comp.  
Terminal  
U-GND  
V-GND  
W-GND  
2MΩ  
2MΩ  
2MΩ  
2MΩ  
2MΩ  
2MΩ  
Check Point  
1. Check the wire connection. (U,V,W)  
2. Check the load condition. (Refrigerant, Pipe length, …) ¡ Adjust the load condition  
3. Check the electricity leakage of the compressor. ¡ Normal : Over 2M.  
4. Check the resistance of compressor. ¡ Normal : 0.65(INV), 0.8(Cons.) ¡ No difference at each terminal.  
5. Check the insulation from water at IPM part. ¡ Check the trace of water.  
6. Check the IPM circuit.  
58 Room Air Conditioner  
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Part 4 Trouble Shooting  
4) Troubleshooting CH21, CH22  
Error  
Title  
Cause of error  
Check point & Normal condition  
code  
Malfunction of compressor  
Blocking of pipe  
Low voltage input  
21  
Max. C/T  
Over current (14A  
)
Refrigerant, pipe length, blocked, …  
Malfunction of current detection circuit.  
(Open / Short)  
The voltage of “C01N” is 4.0VDC(25A)  
C/T  
Internal circuit  
Initial current error  
22  
.
V
-
+
Check Point  
1. Check the power source.  
+ -  
+ -  
2. Check the fan operation is right.  
3. Check the current.  
4. Check the install condition.  
5. Check the internal circuit. (C/T, Diode, Resistor)  
Service Manual 59  
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Part 4 Trouble Shooting  
5) Troubleshooting CH23, CH28  
Error  
Title  
Cause of error  
Check point & Normal condition  
code  
DC Link  
Low voltage.  
• Check the power source.  
• Check the components.  
• DC link volt. is  
23  
140VDC  
.
DC Link  
High voltage  
• DC link volt. is  
• Check the power source.  
• Check the components.  
28  
420VDC  
.
Check Point  
1. Check the power source.  
2. Check the components  
(B/Diode, Reactor, PSC Parts )  
V
60 Room Air Conditioner  
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Part 4 Trouble Shooting  
6) Troubleshooting CH24, CH25  
Error  
Title  
Cause of error  
Check point & Normal condition  
code  
• Check the connection of “CN_Press”.  
• Check the components.  
• Low / High press  
S/W open.  
24  
Press S/W Open  
Input voltage  
Abnormal Input voltage  
(140VAC , 300VAC ).  
• Check the power source.  
• Check the components.  
25  
TRANS1  
50Hz, DC12V  
CN PRESS  
CN TRNAS1  
Check Point  
CH 24  
CH 25  
1. Check the power source.  
1. Check the connection of “CN_PRESS”  
2. Check the install condition for over load.  
3. Check the SVC V/V open.  
2. Check the components  
(Trans1, B/Diode, Diode, Resistance)  
4. Check the leakage of refrigerant.  
Service Manual 61  
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Part 4 Trouble Shooting  
7) Troubleshooting CH26, CH27  
Error  
Title  
Cause of error  
position detect error  
• Over current at “IGBT”  
Check point & Normal condition  
code  
• Check the connection of comp wire “U,V,W”  
• Malfunction of compressor  
• Check the component of “IPM”, detection parts.  
DC Compressor  
• Compressor  
26  
Position  
• Check the component of “IGBT” .  
• Check the components.  
PSC Fault  
27  
E
C
B
C
E
B
Check Point  
CH 26  
CH 27  
1. Check the component of “IGBT”  
1. Check the connection of “U,V,W”  
2. Check the insulation of IPM part.  
3. Check the compressor. (same with CH21)  
2. Check the components  
(IGBT, R04S, NF1, BD02S)  
62 Room Air Conditioner  
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Part 4 Trouble Shooting  
8) Troubleshooting CH32, CH33, CH40  
Error  
code  
Title  
Cause of error  
Check point & Normal condition  
• Check the discharge pipe sensor for INV.  
• Check the install condition for over load.  
• Check the leakage of refrigerant.  
• Check the SVC V/V open.  
D-pipe (Inverter)  
temp. high  
• Discharge sensor  
(Inverter) temp. high  
32  
(105°C(221°F)  
)
• Check the discharge pipe sensor for Cons.  
• Check the install condition for over load.  
• Check the leakage of refrigerant.  
• Check the SVC V/V open.  
D-pipe (Constant)  
temp. high  
• Discharge sensor  
(Cons.) temp. high  
33  
40  
(105°C(221°F)  
)
• Open/Short  
• Soldered poorly  
• Internal circuit error  
CT Sensor  
• Normal resistor : about 0  
D-Pipe temp.  
Toff(105) °C  
(221) °F  
T2(95) °C  
(203) °C  
T1(90) °C  
(194) °C  
COMP Frequency  
Normal  
Normal  
Normal  
Normal  
OFF  
(Hz)  
LEV Openness  
OFF Control  
(Pulse)  
Check Point  
CH 32  
CH 33  
1. Check the install condition for over load.  
2. Check the SVC V/V open.  
1. Check the install condition for over load.  
2. Check the SVC V/V open.  
3. Check the leakage of refrigerant.  
3. Check the leakage of refrigerant.  
4. Check the constant compressor. (same with CH21)  
CH 40  
1. If the resistance of the sensor is only  
possible.  
, the check Is  
2 If the error occurs again after the reset , change the  
PCB.  
Service Manual 63  
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Part 4 Trouble Shooting  
9) Troubleshooting CH41, CH44, CH45, CH46, CH47, CH65  
Display  
code  
Title  
Cause of error  
• Open / Short  
• Soldered poorly  
• Internal circuit error  
Check point & Normal condition  
• Normal resistor : 200k/ at 25°C(77°F) (Unplugged)  
• Normal voltage : 4.5VDC / at 25°C(77°F) (plugged)  
41  
D-pipe sensor (Inverter)  
• Open / Short  
• Soldered poorly  
• Internal circuit error  
• Normal resistor : 10k/ at 25°C(77°F) (Unplugged)  
• Normal voltage : 2.5VDC / at 25°C(77°F) (plugged)  
44  
45  
46  
47  
65  
Air sensor  
• Open / Short  
• Soldered poorly  
• Internal circuit error  
• Normal resistor : 5k/ at 25°C(77°F) (Unplugged)  
Condenser Pipe sensor  
Suction Pipe sensor  
D-pipe sensor (Constant)  
Heat sink sensor  
• Normal voltage : 2.5VDC / at 25°C(77°F) (plugged)  
• Open / Short  
• Soldered poorly  
• Internal circuit error  
• Normal resistor : 5k/ at 25°C(77°F) (Unplugged)  
• Normal voltage : 2.5VDC / at 25°C(77°F) (plugged)  
• Open / Short  
• Soldered poorly  
• Internal circuit error  
• Normal resistor : 200k/ at 25°C(77°F) (Unplugged)  
• Normal voltage : 4.5VDC / at 25°C(77°F) (plugged)  
• Open / Short  
• Soldered poorly  
• Internal circuit error  
• Normal resistor : 10k/ at 25°C(77°F) (Unplugged)  
• Normal voltage : 2.5VDC / at 25°C(77°F) (plugged)  
Check Point  
1. Estimate the resistance of each sensor.(Unplugged)  
2. Estimate the voltage of each sensor.(Plugged)  
3. If the resistance of the sensor is 0 kor , then sensor is abnormal.  
If the voltage of the sensor is 0 V or 5VDC, then sensor is abnormal.  
64 Room Air Conditioner  
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Part 4 Trouble Shooting  
10) Troubleshooting CH51, CH60  
Display  
Title  
Cause of error  
Check point & Normal condition  
code  
• Check the indoor unit capacity.  
• Check the combination table.  
• Over capacity  
Combination  
51  
Over capacity  
EEPROM  
Check sum  
• Check the PCB ASM P/No.  
• Check the poor soldering.  
• Check sum error  
60  
Check Point  
CH 51  
CH 60  
1. Check the insertion condition of EEPROM.  
2. Check the poor soldering  
1. Check the indoor unit capacity.  
Service Manual 65  
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Part 4 Trouble Shooting  
11) Troubleshooting CH61, CH62  
Display  
Title  
Cause of error  
Check point & Normal condition  
code  
Condenser  
pipe sensor  
temp. high  
• Condenser pipe sensor  
detected high  
temp.(65°C(149°F))  
• Check the load condition.  
• Check the sensor of Condenser pipe sensor.  
61  
• Heat sink sensor  
detected high  
temp.(85°C(185°F))  
Heat sink sensor  
temp. high  
• Check the fan is locked.  
• Check the sensor of heat sink.  
62  
Heat Sink temp.  
Toff °C  
T2 °C  
T1 °C  
COMP Frequency  
Normal  
Normal  
OFF  
Normal  
(Hz)  
Check Point  
CH 61  
CH 62  
1. Check the fan is locked.  
1. Check the install condition for over load.  
(Refrigerant, Pipe length, Blocked, …)  
2. Check the Outdoor temp. is very high.  
66 Room Air Conditioner  
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AUGUST, 2007  
P/NO : MFL41161601  
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