Daewoo Frs U20 Service Manual

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1. How to start
1) Press “FRZ.TEMP” button 5 times while pressing 
“REF.TEMP” button at the same time.
2. How to stop
1) Push “FRZ.TEMP” button 1 time.
2) It stops automatically in 4 minutes from the start.
3. All the error codes are reset  if they turn to be normal.
4. Error display
INPUTCONTROL OBJECT
CONTENTS REMARKS  Temperature Control ButtonsLamp LED of Inner control
(Full down mode and forced defrost mode are displayed while pressing
“REF.TEMP” button at the error display mode)
REF. LED “1” is...

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5. Control way of Errors (if any)
1) “F-sensor” error
Cause : F-sensor open or short
Control : Condition of ambient temperature
How to reset : If F-sensor is normal, the error is terminal temperature.
CONTENTS REMARKS 
2) “R-sensor” error
Cause : R-sensor open or short
Control : Condition of ambient temperature
How to reset : If R-sensor is normal, the error is terminal temperature.
3) “RT-sensor” error
Cause : RT-sensor open or short (full down)
Control : Normal operation, deletion of control by...

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1. How to start
1) Under “LOCK” mode, press “SUPER FREEZER” button 5 times while pressing 
“FREEZER SET” button at the same time.
2) The front CLED displays as the right diagram shows 
( [Ex.] Time Display of 0003 signifies 3 minutes of power on time.)
3) Press “FREEZER SET” button and the following value is displayed successively.
①Time
②F-Sensor temperature
③D-Sensor temperature
④R-Sensor temperature
⑤RT-Sensor temperature
⑥P Factor display (Refer to water supply mode of automatic icemaker)
⑦Filter...

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1) “F1” error
Cause : F-sensor disconnection or short
Check point : Measure the resistance between both terminals after separating CN8 (or CN15)
of the Main PCB. (Refer to the 5-2.)
If F-sensor is disconnected or shorted , change the F-sensor in the freezer compartment.
How to reset : If F-sensor is normal, the error is terminal temperature.
CONTENTS REMARKS 
2) “R1” error
Cause : R-sensor disconnection or short
Check point : Measure the resistance between both terminals after separating CN7 (or...

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9) “EI”ERROR
Cause : I-SENSOR disconnection / short
Check point : Measure the resistance between both terminals after separating CN11
of the Main PCB. (Refer to the 5-2.)
If F-sensor is disconnected or shorted , change the I-sensor in the automatic ice maker.
CONTENTS REMARKS 
10) “EF” ERROR
Cause : When Flow-sensor ERROR (There is no Pulse during some time)
The number of pulse signal is below 10 by 1 sec during water supply.
Check point : Water supply line
13) “Ea” error
Cause : Malfunction of ice...

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Element A/S Function
INPUTCONTROL OBJECT
CONTENTS REMARKS  Each buttonResistance of R-sensor Mid ON/OFF Point
“REF.TEMP”+ “FRZ.TEMP” 5 times Error display“FRZ.TEMP”+ “FRZ.DOOR” OPEN/CLOSE 5 times Demo function“REF.TEMP”+ “FRZ.DOOR” OPEN/CLOSE 5 times Pull Down“FRZ.TEMP” + “REF.TEMP” 5 times Forced Defrosting
1. All the modes are started “LOCK” mode (except “FILTER RESET” mode)
2. Element A/S Function
INPUTCONTROL OBJECT
CONTENTS REMARKS  Each buttonResistance of R-sensor Mid ON/OFF Point
“WATER/ICE” +...

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1. Filter Exchange Information : Record as a real-time from the point of 
power input
2. P Factor (Information about Ice Maker)
INPUTCONTROL OBJECT
CONTENTS REMARKS  None
1. F-FAN, R-FAN, C-FAN 
INPUTCONTROL OBJECT
CONTENTS REMARKS  Full ice sensing switch
Ice Maker Lock
Sensors Ice separating motor
1. Flow of ice making
1) Press TEST switch under the Icemaker for more than 1 second and test starts.
* Test mode starts from ice separating mode.
* In case test switch has an error of short, test is done...

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CONTENTS REMARKS 
2) With the initial power input, Ice tray turns to be horizontal and ice making
mode starts.
3) Control of water hose heater
* Heater is always ON if RT-sensor has an error or RT is below 15 degree.
* Heater is always ON for 60 minutes (max. Limit time) if Flow-sensor has
an error
4) Water supply stand-by
Condition : if ice is sensed full
Operation : proceeds to Ice making mode (Ice separating and water supply Modes stop)
5) Crusher Function
It stops operation when freezer door is...

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CONTENTS REMARKS 
3. Ice separating (drop) mode
CCWCWSTOPCWmotor
revolutionlevel SW status of
ice tray
Horizontal position Ice separation start
8~11secMAX1.1sec 8.5~12.2sec 0.2sec
normal 
level SW
level SW
error1.1 sec 11 sec 10 sec
1) Time of each zone used to verify level switch error
2) The rotation of motor is sensed at each zone
3) In case of level switch error, ice separation is done by time.
4) If ice separating motor has error, the mode stop.
4. Water supply mode
START
Water supply valve ON...

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CONTENTS REMARKS 
1) Water supply valve is open when water supply mode starts after separation of ices.
2) Water is supplied by time in case sensor has error.
3) Factor valve is variable which can be useful in AS action
①Water flow pulse is set to 238 if flow sensor is in normal condition.
(If water is supplied by time, maximum water supply time 165 seconds)
②In case water flow sensor has error, water time is 5.5 seconds.
5. Water supply check mode
5 minutes after water supply the status can be...