Friedrich AS - W126BMS0 User manual

Room Air Conditioner
SVC MANUAL(General)
CAUTION
Before Servicing the unit, read the safety
precautions in General SVC manual.
Only for authorized service personnel.
960-914-06

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Air Conditioner Service Manual
CONTENTS
Part 1 General Information
1. Safety Precautions........................................................................................................4
2. Nomenclature ...............................................................................................................7
Part 2 Functions & Controls
1. List of Functions & Controls........................................................................................9
2. Basic Mode Controls .................................................................................................10
3. Special Mode Controls ...............................................................................................12
4. Utility Functions .........................................................................................................13
Part 3 Test Run
1. Check before Test Run ...............................................................................................17
2. Test Run Flow chart ....................................................................................................18
3. Test Run Detail ............................................................................................................19
Part 4 Trouble Shooting Guide
1. 2-Way, 3-Way Valve ....................................................................................................21
2. Pumping Down ...........................................................................................................22
3. Evacuation (All amount of refrigerant leaked) ........................................................23
4. Gas Charging (After Evacuation) ..............................................................................24
5. Cycle Troubleshooting Guide ....................................................................................25
6. Electric Parts Troubleshooting Guide.......................................................................28
7. Self-diagnosis Function .............................................................................................32
■Indoor Unit Error .................................................................................................... 32
■Outdoor Unit Error ..................................................................................................34
■Trouble Shooting Guide (Indoor Unit)....................................................................36
■Trouble Shooting Guide [Outdoor Unit (2 LED Type)] ..........................................41
■Trouble Shooting Guide [Outdoor Unit (1 LED Type)] ..........................................56

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1. Safety Precautions ............................................................................................................4
2. Nomenclature......................................................................................................................7
Part 1 General Information

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Part 1 General Information
1. Safety Precautions
1.1 Cautions in Repair
To prevent injury to the user or other people and property damage, the following instructions must be followed.
■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.
■Meanings of symbols used in this manual are as shown below.
Be sure not to do.
Be sure to follow the instruction.
Dangerous Voltage
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 shortage
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 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.
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 repair the product with wet hands. Holding the plug by
hand when taking out. Otherwise there is risk of electric shock or fire.

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Part 1 General Information
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.
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

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Part 1 General Information
2. Nomenclature
2.1 Global Model Name
Code Type Code of Model Meaning
1 Production Center, A~Z L: Chang-won R22
Refrigerant A: Chang-won R410A
U: Tianjin R410A
2 Product Type A~Z S: Split Type Air Conditioner
3 Cooling/Heating/Inverter A~Z 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 Capacity 0~9 Cooling/Heating Capacity
Ex. "09" →9,000 Btu/h
6 Electric Range 1~9 1: 115V/60Hz
A~Z 2: 220V/60Hz
3: 208-230V/60Hz
5: 200-220V/50Hz
6: 220-240V/50Hz
7: 110V, 50/60Hz
7 Chassis A~Z Name of Chassis
8 Look A~Z Look,
Color (Artcool Model)
9 Function A~Z
10 Serial No. 1~9 Model Development Serial No.
12 -345678910
Basic A
Basic+4Way B
Basic+Deodorizing Filter (Carbon filter) C
Plasma+(A/changeove)+A/clean+2Way+Ion E
Plasma+(A/changeove)+A/clean+4way+Ion+Lamp F
Plasma+(A/changeove)+A/clean+Low A G
Plasma+(A/changeove)+A/clean+4way+Low A H
Plasma+(A/changeove)+A/clean L
Plasma+(A/changeove)+A/clean+4way M
Plasma+(A/changeove)+A/clean+PTC N
Plasma+(A/changeove)+Autoclean+4way+PTC P
Plasma+(A/changeove)+A/clean+4way+Low A+PTC Q
Smart(Robot) Cleaning R
Eco eye+Plasma+Allergy Filter+4way S
Plasma+Allergy Filter+4way U
Allergy Filter+4way V
Allergy Filter+2way W
Basic+Low Ambient Y
Basic+(A/clean)+4way+Low A Z
AS-W126BMS0

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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

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Part 2 Functions & Controls
1. List of Functions & Controls
Cooling Mode
Heating Mode
Healthy Dehumidification
Auto Changeover
Jet Cool
Jet Heat
Energy saving
Forced operation
Auto Clean
Air volume control
Natural Air control
Auto Swing
Sleep mode Auto control
Auto Restart Function
Category Function Description Remark
Cooling operation
Heating operation
Dry operation
Cooling mode is automatically changed to heating mode and
vice versa
Powerful cooling mode
Powerful heating mode
Air volume & set temp. are automatically selected for saving
energy in cooling mode
Operation without remote controller
After cooling operation, this function makes the evaporator
dry
Indoor Fan speed Control
Air volume control Program
Vertical Airflow Direction control
Air volume & set temp. are automatically changed for com-
fortable sleep
When power returns after a power failure, Unit restarts in the
previous operating mode
Basic mode
controls
Special Mode
controls
Utility Functions
NOTE: The Exploded View SVC Manual has the particular Function table for each model.

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Part 2 Functions & Controls
2. Basic Mode Controls
2.1 Cooling Mode
Setting
Temp.
-0.5C(-1F)
+0.5C(1F)
Comp. OFF
Thermo ON
Thermo OFF
INV. Comp.
Frequency LowHigh LowHigh
• 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 90
seconds. ( not emergency conditions)
• Compressor turned off when
- Intake air temperature reaches below 0.5°C(1°F) of the setting temperature for three minute continuously.
- Intake air temperature reaches below 1.5°C(3°F) of the setting temperature
• Compressors 3 minute time delay.
- After compressor off, the compressor can restart minimum 3 minute later.
2.2 Heating Mode
2˚C(3.6˚F)
4˚C(˚F)
Comp. OFF
INV. Comp.
Frequency LowHigh LowHigh Comp. OFF
Setting
Temp.
Thermo ON
Thermo 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 90 sec-
onds.
• Condition of compressor turned off
- When intake air temperature reaches 4°C(°F) above the setting temperature.
• Condition of compressor turned on
- When intake air temperature reaches below 2°C(3.6°F) of above the setting temperature.
* Condition of indoor fan turned off
• While in defrost control, the indoor and outdoor fans are turned off.
• Compressor 3 minute delay
- After compressor off, the compressor can restart minimum 3 minute later.

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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.
•
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 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.
Intake air Temp. Setting Temp.
26°C(78.8 °F) ≤ intake air temp. 25°C(77 °F)
24°C(75.2 °F) ≤ intake air temp.< 26°C(78.8 °F) intake air temp. -1°C(-2 °F)
22°C(71.6 °F) ≤ intake air temp. < 24°C(75.2 °F) intake air temp. -0.5°C(-1 °F)
18°C(64.4°F) ≤ intake air temp. < 22°C(71.6 °F) intake air temp.
intake air temp. < 18°C(64.4 °F) 18°C(64.4 °F)
+0.5C(+1F)
-0.5C(-1F)
-2C(-4F)
+4C(+8F)
+2C(+4F)
Cooling thermo off
Heating thermo off
Switching point
Switching point
Setting
Temp.
Cooling
operation Heating operation Cooling operation
Mode

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Part 2 Functions & Controls
3. Special Mode Controls
3.1 Jet Cool operation
• In the heating mode or Auto Changeover operation, the Jet cool function does not work.
When it is input while in other mode of operation (cooling, dehumidification, Air purification, Air circulation), 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 horizontal 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 Auto Changeover 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 horizontal 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.

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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.
• 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.
Indoor temp.
over 24°C(75.2°F)
21~24°C(69.8~75.2°F)
below 21°C(69.8°F)
Setting temp.
22°C(71.6°F)
23°C(73.4°F)
24°C(75.2°F)
Setting speed of
indoor fan
High speed
Operating Mode
Cooling
Healthy Dehumidification
Heating
Comp. ON OFF
Setting Step Super Low
Indoor Fan
ON
Cooling CYCLE
OFF
30 Min
Fan

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Part 2 Functions & Controls
4.3 Air volume control
• UIndoor fan motor control have 6 steps or 8 steps.
• UAir volume is controlled "SH", "H", "MH", "M", "ML", "L" by the
remote controller.
• "SL" step is selected in "Sleep Mode" operation.
4.4 Natural Air Control(Natural 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 Auto Swing
• By the Auto swing key input, the horizontal vane automatically operates with the Auto swing or it is fixed to the desired
direction.
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°F).
After another 30minutes lapse, it increases again by 1°C(2°F).
SL Super Low
L Low
ML Medium-Low
M Medium
MH Medium-High
H High
SH Super High
Auto Natural Wind
Step Description
NOTE: Some Models are different by swing width and swing pattern.
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)

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Part 2 Functions & Controls
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°F).
After another 60minutes lapse, it decreases again by 1°C(2°F).
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
- Auto Swing
Setting temp. (°C)
Heating ON temp.
(Setting temp)
Heating OFF temp.
(Setting temp. +4.0°C(+8°F))
1 2 Sleep time (hr)
1.0°C(2°F) down
1.0°C(2°F) down

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Part 3 Test Run
1. Check before Test Run...................................................................................................17
2. Test Run Flow chart .......................................................................................................18
3. Test Run Detail................................................................................................................19

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Part 3 Test Run
Check to see whether there is any refrigerant leakage, and check whether the power or transmission
cable is connected properly.
NOTE: Check that there should be no disconnection when all pins and wires are pulled by hands.
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 MΩ or more between power supply terminal block and
ground. Do not operate in the case of 2.0 MΩ or less.
NOTE: Never carry out mega ohm check over terminal control board.
Otherwise the control board may break.
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 MΩ as a result of refrigerant accumulation in the internal
compressor.
If the insulation resistance is less than 2.0 MΩ, turn on the main power supply.
1
2
3
1. Check before Test Run

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Part 3 Test Run
Is cold air discharged for
more than 3 minutes ?
START
Test operation for indoor unit
Operation mode change
to Heating mode
Operate the unit in cooling mode.
Does Test operation start?
Refer to part4, 6 Electric part
Yes
No
Yes Refer to part4, 5 Cycle part
No
Is hot air discharged ?
After Hot Start
NOTE: When outdoor temperature is low,the unit is operated to Heating mode
Yes
No
Is there any temperature
difference between intake and
discharged air?
Yes
No
Is the operating current
normal ?
Yes
Normal
Refer to Troubleshooting
Guide
No * Check the load (In/Out Temp.)
* Check pipe length and amount of
refrigerant
* Check for abnormal sound in
outdoor unit (comp.,Fan, others )
2. Test Run Flow chart

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Part 3 Test Run
1. Check that all tubing and wiring have been properly con-
nected.
2. Check that the gas and liquid side service valves are fully
open.
3. Check that all pins and wires have been connected thor-
oughly by pulling with hands.
Settlement of outdoor unit
• Anchor the outdoor unit with a bolt and nut(ø10mm) tightly
and horizontally on a concrete or rigid mount.
• 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.
• In the case when the vibration of the unit is conveyed to the
hose, secure the unit with an anti-vibration bushing.
NOTE: If the actual pressure is higher than shown, the
system is most likely over-charged, and charge
should be removed.
If the actual pressure are lower than shown, the
system is most likely undercharged, and charge
should be added.
The air conditioner is now ready for use.
5. Check operating current.
6. Change operation mode and check.
Evaluation of the performance
Operate unit for 15~20 minutes, then check the system
refrigerant charge:
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).
4. For reference; the gas side pressure of optimum condition
is as below.(Cooling)
Bolt
Tubing connection
Discharge
temperature
Discharge air
Intake temperature
R22 35°C (95°F) 4~5kg/cm2G(56.8~71.0 P.S.I.G.)
R410A 35°C (95°F) 8.5~9.5kg/cm2G(120~135 P.S.I.G.)
Outside ambient
TEMP.
Refrigerant The pressure of the gas side
service valve.
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.
CAUTION:
Be sure to perform Pump Down procedure with the unit in
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.
3. Close the liquid side service valve(all the way in).
4. Turn on the unit's operating switch and start the cooling
operation.
5. When the low-pressure gauge reading becomes 1 to
0.5kg/cm2G(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.
PUMP DOWN
3. Test Run Detail

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Part 4 Trouble Shooting
1. 2-Way, 3-Way Valve ........................................................................................................21
2. Pumping Down ..............................................................................................................22
3. Evacuation (All amount of refrigerant leaked) ............................................................23
4. Gas Charging (After Evacuation) .................................................................................24
5. Cycle Troubleshooting Guide .......................................................................................25
6. Electronic Parts Troubleshooting Guide......................................................................26
7. Self-diagnosis Function.................................................................................................30