LG LSWS305ST User manual

1
30” ELECTRIC CONVECTION
BUILT-IN OVEN
SERVICE MANUAL
MODEL: LSWS305ST
CAUTION
BEFORE SERVICING THE UNIT, READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
P/NO : MFL37118308
March, 2010
Printed in Korea
삼흥
정판
Internal Use Only
Website http://biz.lgservice.com

This LG Service Manual, “30” Electric Built-in Oven”, provides the technician with information on
the operation and service of the Electric Built-in Oven. It is to be used as a training Service
Manual. For specific information on the model being serviced, refer to the “Owner’s Manual” or
“Tech Sheet” provided with the electric oven.
SAFETY PRECAUTIONS
• Repairs of the appliance should be carried out by a licensed technician only. Incorrect repairs
may result in dangerous situations. If you need repairs, contact an LG Service Center or your
dealer.
• If the power cord is defective, it must be replaced by a qualified service agent with a UL listed
range cord.
• Electrical leads and cables should not be allowed to touch the oven.
• Rating plate is located on the bracket below the control panel.
• The power supply of the appliance should be turned off when it is being repaired.
FORWARD
LG Electronics assumes no responsibility for any repairs made
on our products by anyone other than Authorized Service Technicians.
WARNING
• DISCONNECT power supply cord from the outlet before servicing.
• Replace all panels and parts before operating.
• RECONNECT all grounding devices.
- Failure to do so can result in severe personal injury, death or electrical shock.
• DO NOT Touch when the oven operates.
- The interior parts will be very hot.

(P AGE )
GENERAL -------------------------------------------------------------------------------------------- 1-1 ~ 1-6
• Read all instructions before use --------------------------------------------------------------------------------- 1-1 ~ 1-4
• Model & Serial number label and tech sheet locations ----------------------------------------------------------- 1-5
• Specifications ------------------------------------------------------------------------------------------------------------------ 1-6
USING YOUR OVEN
---------------------------------------------------------------------------- 2-1 ~ 2-5
• General information --------------------------------------------------------------------------------------------------------- 2-1
• Control panel feature ------------------------------------------------------------------------------------------------ 2-2 ~ 2-5
- Setting the initial control
- Start, clear/off
- Oven light
- Timer
- Control lockout
- Set up: 8 different category
1) Language selection
2) Temperature selection unit
3) Display brightness
4) Sound volume Loud/Normal/Mute
5) Convection auto conversion
6) Temperature adjustment
7) Clock time
8) Reset
- Bake
- Timed cook, Delayed timed cook
- Broil
- Roast
- Convection bake
- Crisp convection
- Convection roast
- Recipe bank
- Proof/Warm
- Healthier roast
- My menu
- Option
- Self clean
DISASSEMBLY INSTRUCTIONS ---------------------------------------------------------- 3-1 ~ 3-3
• Component Locations ---------------------------------------------------------------------------------------- 3-1
DISASSEMBLY INSTRUCTIONS ----------------------------------------------------------- 3-2 ~ 3-3
• Replacing the control panel and related components --------------------------------------------------------- 3-2~3-3
- Removing the Low Voltage Transformer (controller) -------------------------------------------------------------- 3-2
- Removing the Relay PCB ------------------------------------------------------------------------------------------------- 3-3
- Removing the door lock assembly -------------------------------------------------------------------------------------- 3-3
- Removing the Low Voltage Transformer (halogen lamp) -------------------------------------------------------- 3-3
- Removing the Serge filter ------------------------------------------------------------------------------------------------- 3-3
DISASSEMBLY INSTRUCTIONS ------------------------------------------------------------ 3-4 ~ 3-5
• Replacing oven cavity components ------------------------------------------------------------------------------- 3-4 ~ 3-5
- Removing the Broil element ---------------------------------------------------------------------------------------------- 3-4
- Removing the Convection element ------------------------------------------------------------------------------------- 3-4
- Removing the Blade fan --------------------------------------------------------------------------------------------------- 3-5
- Removing the Halogen lamp & socket assembly ------------------------------------------------------------------ 3-5
• Replacing other electrical components. -------------------------------------------------------------------------- 3-6 ~ 3-9
TABLE OF CONTENTS

- Removing the Vent motor ------------------------------------------------------------------------------------------------- 3-6
- Removing the Thermal limiter ------------------------------------------------------------------------------------------- 3-7
- Removing the Door switch ----------------------------------------------------------------------------------------------- 3-7
- Removing the Thermal limiter (Double Line Break)
--------------------------------------------------------------- 3-8
- Removing the Convection motor assembly ------------------------------------------------------------------------- 3-8
- Removing the Hidden bake element --------------------------------------------------------------------------- 3-8 ~ 3-9
DISASSEMBLY INSTRUCTIONS
-------------------------------------------------------- 3-10 ~ 3-13
• Removing & Reinstalling the lift-off oven door ----------------------------------------------------------------------- 3-10
• Removing the oven door handle & glass --------------------------------------------------------------------- 3-11 ~ 3-12
• Removing the oven door gasket ------------------------------------------------------------------------------------------ 3-13
COMPONENT TEST ----------------------------------------------------------------------------- 4-1 ~ 4-4
•
Convection motor ------------------------------------------------------------------------------------------------------------- 4-1
• Door locking motor ----------------------------------------------------------------------------------------------------------- 4-2
• Door locking micro switch ------------------------------------------------------------------------------------------------- 4-2
• Low Voltage Transformer - Controller -------------------------------------------------------------------------------- 4-2
• Low Voltage Transformer - Halogen lamp -------------------------------------------------------------------------- 4-2
• Oven Thermistor -------------------------------------------------------------------------------------------------------------- 4-3
• Door switch --------------------------------------------------------------------------------------------------------------------- 4-3
• Oven lamp ---------------------------------------------------------------------------------------------------------------------- 4-3
• Broil Element ------------------------------------------------------------------------------------------------------------------- 4-4
• Bake Element ------------------------------------------------------------------------------------------------------------------ 4-4
• Convection element --------------------------------------------------------------------------------------------------------- 4-4
• Vent motor ---------------------------------------------------------------------------------------------------------------------- 4-4
DIAGNOSIS THROUGH SCHEMATIC ----------------------------------------------------------- 5-1
HOW TO ENTER THE TEST MODE
--------------------------------------------------------------- 5-2
SAFETY CAUTION & ERROR CODE SUMMARY
-------------------------------------------- 5-3
CHECKING FLOW CHART BY FAILURE MODE
-----------------------------------
5-3 ~ 5-18
• Dead -----------------------------------------------------------------------------------------------------------------------
5-4 ~ 5-8
• Oven does not heat (including F-9 error)
---------------------------------------------------------------------
5-9 ~ 5-12
• Not operating Key (including F-3 error)
-------------------------------------------------------------------------------- 5-13
• Lock system failure (including F-10 error) ------------------------------------------------------------------- 5-14 ~ 5-15
• Oven Thermistor failed (including F-1, F-2 error) ------------------------------------------------------------------- 5-16
• Oven too hot (including F-6 error) --------------------------------------------------------------------------------------- 5-17
• Communication error
→→
F-10 error ------------------------------------------------------------------------------------- 5-18
SCHEMATIC DIAGRAM -------------------------------------------------------------------------------- 6-1
• Strip circuits ------------------------------------------------------------------------------------------ 6-2 ~ 6-5
EXPLODED VIEW
-------------------------------------------------------------------------------
7-1 ~ 7-6
REPLACEMENT PARTS LIST
-------------------------------------------------------------- 8-1 ~ 8-3

1-1
GENERAL
READ ALL INSTR
READ ALL INSTRUCTIONS BEFORE USE UCTIONS BEFORE USE
Read and follow all instructions before using your oven to prevent the risk of fire, electric shock, injury to person, or
damage when using the range. This guide don’t cover all possible conditions that may occur. For further assistance
contact your service agent or manufacturer.
This is the safety alert symbol. This symbol alerts you to potential hazards that can kill or hunt you
and others. All safety messages will follow the safety alert symbol and either the word “WARNING”
or “CAUTION”. These word means :
This symbol will alert you to hazards or unsafe practices which could cause
serious bodily harm or death.
WARNING
This symbol will alert you to hazards or unsafe practices which could cause
bodily injury or property damage.
CAUTION
WARNING
• NEVER use your appliance for warming or heating the room.
• DO NOT use water on grease fires.
- Turn off the oven to avoid spreading the flames. Smother the fire by closing the oven door or use dry chemical,
baking soda, or foam-type extinguishers.
• Use only dry pot holders.
- Moist or damp pot holders on hot surfaces may result in burns from steam. Do not let the pot holder touch hot
heating elements. Do not use a towel or other bulky cloth.
• Storage in or on appliance.
- Flammable materials should not be stored in an oven or near surface elements.
• Wear proper apparel.
- Loose-fitting or hanging garments should never be worn while using the appliance.
• DO NOT place aluminum foil directly on the oven bottom.
• Children should be kept away from the oven.
- Accessible parts may become hot when the broil is use.
• DISCONNECT power supply cord from the outlet before servicing.
• Replace all panels and parts before operating.
• RECONNECT all grounding devices.
- Failure to do so can result in severe personal injury, death or electrical shock.
• DO NOT Touch when the oven operates.
- The interior parts will be very hot.
• ELECTRIC SHOCK HAZARD
- Unit must be disconnected from electrical outlet when making repairs, replacements, adjustments. Replace all
panels before operating oven. Failure to do so can result in death or electrical shock.
CAUTION
• DO NOT leave children alone.
- Children should not be left alone or unattended in area where appliance is in use.
- Children should never be allowed to sit or stand on any part of the appliance.
• DO NOT leave small children unattended near the appliance.
- During the self-cleaning cycle, the outside of the oven can become very hot to touch.
• Be careful when you work on the electric oven handling the sheet metal part.
- Sharp edge may be present and you can cut yourself.
• Be careful not to bend the fan blade.
• The door is very heavy. Be careful when removing and lifting door. Do not lift the
door by the handle.

1-2
GENERAL
READ ALL INSTR
READ ALL INSTRUCTIONS BEFORE USE UCTIONS BEFORE USE
SAFETY PRECAUTIONS
• Be certain your appliance is properly installed
and grounded by a qualified technician.
• Do not repair or replace any part of the
appliance unless specifically recommended in
the manual.
• All other servicing should be referred to a
qualified technician.
• Always disconnect power to appliance before
servicing by unplugging, removing the fuse or
switching off the circuit breaker.
• DO NOT TOUCH HEATING ELEMENTS OR
INTERIOR SURFACES OF OVEN.
Heating elements may be hot even though they
are dark in color. Interior surfaces of an oven
become hot enough to cause burns. During and
after use, do not touch or let clothing or other
flammable materials contact heating elements
or interior surfaces of oven until they have had
sufficient time to cool. Other surfaces of the
appliance may become hot enough to cause
burns. Among these surfaces are oven vent
openings and surfaces near these openings,
oven doors, and windows of oven doors.
• Use Care When Opening Door.
Let hot air or steam escape before you remove
or replace food in the oven
• Do Not Heat Unopened Food Containers.
Build-up of pressure may cause container to
burst and result in injury.
• Keep Oven Vent
Ducts Unobstructed.
The oven vent could
become hot during
oven use. Never block
this vent and never
place plastic or heat-
sensitive items on or
near the vent.
NOTE:
For proper operation vent trim must be installed.
• Be certain all packing materials are removed
from the appliance before operating.
Keep plastics, clothes, and paper away from
parts of the appliance that may become hot.
• DO NOT force the door open.
This can damage the automatic door locking
system. Use care when opening the oven door
after the self-cleaning cycle. Stand to the side of
the oven when opening the door to allow hot air
or steam to escape. The oven may still be
VERY HOT.
• DO NOT use a steel-wool pad.
It will SCRATCH the surface.
• DO NOT use harsh etching, abrasive
cleaners or sharp metal scrapers to clean
the oven door glass since they can scratch
the surface.
It may result in shattering of the glass.
•
Be careful when removing and lifting the door.
• DO NOT lift the door by the handle.
The door is very heavy.
• DO NOT step or sit on oven door.
Be sure to follow proper installation instructions.
ELECTRICAL SAFETY
• Protective Liners. Do not use aluminum foil or
any other material to line the oven bottoms.
Improper installation of these liners may result
in a risk of electric shock or fire.
• Do Not allow aluminum foil or meat probe to
contact heating elements.
Metal bottom
trim (Vent)
WARNING
• DO NOT place aluminum foil directly
on the oven bottom.
Aluminum foil

1-3
GENERAL
READ ALL INSTR
READ ALL INSTRUCTIONS BEFORE USE UCTIONS BEFORE USE
• Before replacing your oven light bulb, switch
off the electrical power to the oven at the
main fuse or circuit breaker panel.
Failure to do so can result in severe personal
injury, death, or electrical shock.
• DO NOT line the oven walls, racks, bottom,
or any other part of the oven with aluminum
foil or any other material.
Doing so will disrupt heat distribution, produce
poor baking results and cause permanent
damage to the oven interior (aluminum foil will
melt to the interior surface of the oven.)
SAFETY DURING USE
• Oven Racks. Always place oven racks in
desired position while oven is cool.
• Always use pot holders or oven mitts when
removing food from the oven.
You can be burned because cookware and
plates will be hot.
• Use caution with the TIMED BAKE or
DELAYED TIMED BAKE features. Use the
automatic timer when cooking cured or
frozen meats and most fruits and
vegetables. Foods that can easily spoil,
such as milk, eggs, fish, meat or poultry,
should be chilled in the refrigerator first.
Even when chilled, they should not stand in
the oven for more than 1 hour before
cooking begins, and should be removed
promptly when cooking is completed.
Eating spoiled food can result in sickness from
food poisoning.
• Should an oven fire occur, leave the oven
door closed and turn the oven off. If the fire
continues, throw baking soda on the fire or
use a fire extinguisher.
• DO NOT put water or flour on the fire.
Flour may be explosive and water can cause a
grease fire to spread and cause personal injury.
• DO NOT use the broiler pan without the grid.
DO NOT cover the grid with aluminum foil.
CHILD SAFETY
WARNING
• Children should be kept away
from the oven.
• Accessory parts will become hot
when the broiler is in use.
CAUTION
• Children should not be left alone
or unattended in area where
appliance is in use. Children
should never be allowed to sit or
stand on any part of the
appliance.
CAUTION
• DO NOT leave small children
unattended near the appliance.
During the self-cleaning cycle, the
outside of the oven can become very hot
to the touch.

1-4
GENERAL
READ ALL INSTR
READ ALL INSTRUCTIONS BEFORE USE UCTIONS BEFORE USE
SAFETY WHEN CLEANING
• Do Not Clean Door Gasket. The door gasket is
essential for a good seal. Care should be taken
not to rub, damage, or move the gasket.
• Do Not Use Oven Cleaners. No commercial
oven cleaner or oven liner protective coating of
any kind should be used in or around any part
of the oven.
• Before self cleaning the oven. Remove broiler
pan, all oven racks, meat probe and any other
utensils from the oven cavity.
• Never keep pet birds in the kitchen. The
health of birds is extremely sensitive to the
fumes released during an oven self-clean cycle.
Fumes may be harmful or fatal to birds. Move
birds to well-ventilated room.
• Important Instruction. In the event the self
clean error code Fis displayed, and error
melody sounds, the oven is malfunctioning in
the self clean mode. Switch off the electrical
power to the main fuse or breaker and have
serviced by a qualified technician.
• Make sure oven lights are cool before
cleaning.
• DO NOT block the oven vent during
operation.
This can damage the electric parts of the oven.
Air must be able to move freely. The metal
bottom trim (vent) should be properly
assembled on the front bottom of oven before
installing the oven door.
Metal bottom trim
(Vent)

1-5
GENERAL
MODEL & SERIAL NUMBER LABEL AND
MODEL & SERIAL NUMBER LABEL AND
TECH SHEET LOCA
TECH SHEET LOCATION TION
The Model/Serial Number label and Tech Sheet locations are shown below.
Model & Serial
Number Location
Tech Sheet Location

Product Specification List
No Items Specifications Remarks
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
Model name
Rating power source
Heat source
Max power
Max input current
Rating power consumption
& Rating input current
Efficiency
Control style
Display
Power control range
Capacity (Overall, W×H×D)
Capacity (Usable)
Cut out size ( W×H×D )
Unit Dimension
Net Weight
Packing size
Packing weight
Stack height
North American market
Single phase & 4-wires
120/208V : 3.0 KW
Front ceiling area
Left & right sides
Liquid Crystal Display
At bake mode
24 1/2 × 17 11/16 × 18 5/8
23 5/8 × 13 9/16 × 17 3/16
28 1/2 × 28 15/16 × 23 1/2
29 3/4 × 29 5/16 × 24 3/8
154 lbs
33 × 34 × 30
187 lbs
LSWS305ST Built-in Single wall oven
240 V~ 60 Hz
Sheath heater & Carbon heater
4.1 KW
17.3 A
Bake 2,500W / 10.4A
Broil 4,000W / 16.7A
Convection 2,500W /10.4A
Lamp 12V/10W/0.8A
Lamp (12V/10W/0.8A × 2)
Cooling motor 120V/41W/0.34A
Convection motor 120V/42W/0.65A
Locking motor 120V/3.5W/0.03A
Higher than 80%
Touch screen, glass touch & Micom
White LCD
170~550˚F (77~288˚C)
4.7 cu.ft (622 × 449 × 474 )
3.2 cu.ft (601 × 345 × 436 )
724 × 735 × 596
755 × 745 × 619
71 Kg
838 × 864 × 762
81 Kg
3 levels
1-6
GENERAL
SPECIFICA
SPECIFICATIONS TIONS