Tuesday, December 22, 2015

ELECTROLUX EWFH12280W Diagnostics and electronic part description


Electronic parts 
The electronic control consists of two electronic boards:display board and a power board
Through the display board it is possible to set the functions of the drying top: switch it on, set the temperature, the drying cycle duration and pushing the START/PAUSE button, to start it. The settings are displayed through the switching on of the LEDs (four to indicate the duration of the cycle and three to indicate the relative temperature). Depending on the settings, the power board powers the various components: fan and heater.
The temperature is regulated by the NTC sensor and in case of overheating the thermostats with manual reset intervene.
In some washing machine models, the drying top replaces the work top and the fixing is the same. The power supply occurs by means of a connector located in the electric circuit of the washing machine and inserted in the power board of the top. When the drying top is integrated in the washing machine, it takes the function of main appliance and its operation has the priority. Therefore, if a drying cycle is being performed, automatically the power supply to the washing machine is excluded and it is not possible to start a washing cycle. If a washing cycle is being executed and by accident the ON/OFF button of the top is pressed, automatically the cycle is interrupted and the top is in stand-by.
Buttons and LEDs
Button PL1 ON/OFF
It has the function of switching on and off the top.
When it is switched on, the combined appliance (in this case the washing machine) is excluded.
Pushing it sequentially, it is possible to vary the drying temperature and this variation is indicated by the switching on of the LEDs DL3÷DL1.
When it is switched on, the top sets for the more delicate drying cycle turning on LED DL3.
Pushing it sequentially, it is possible to vary the drying time and this variation is indicated by the switching on of the LEDs DL7÷DL4.
When it is switched on, the top sets for the shorter drying cycle turning on LED DL7.
Pushing it sequentially, it is possible to start the drying programme or pause the cycle, to modify the settings previously selected.
Internally there is a LED DL8 which flashes during the setting phase, in pause and at the end of the cycle, while during the execution of the cycle it is on with a fixed light.
Access to diagnostics
Switch off the appliance removing the plug from the socket.
1. Insert the plug into the socket and within two seconds push the buttons simultaneously.
PL2 and PL4
The diagnostic cycle starts:
checking all LEDs (switching on each LED for 0.5”)
checking the buzzer with a long BEEP
If the diagnostic cycle does not identify any faulty component, all LEDs light up till the end of the test and the buttons and the relays are now checked.
If some faults are identified, all LEDs flash (and the check of the buttons and relays can not be executed).checking the buttons and the relative relays:
Push button PL4 (START/PAUSE) and the relay which powers the drying top activates.
Push button PL3 (TIME) and the relay which powers the fan activates.
Push button PL2 (TEMPERATURE) and the relay which powers the heater activates (during this check the temperature control is active in order to avoid the damages caused by the too high temperature).
Push button PL1 (ON/OFF) and the relay which powers the drying top deactivates, the appliance switches off.
End of diagnostic cycle
It is possible to interrupt the diagnostic cycle at any time pushing button PL1 (ON/OFF).
If during the diagnostic cycle a power failure occurs, when it is restored, the appliance switches OFF.
After the switching on of all the LEDs, five minutes remain to perform the last phase of the diagnostic cycle (check of buttons and relays), then the appliance switches off.
Exiting the diagnostic system
To exit the diagnostic system, switch off the appliance.
The appliance is normally supplied by the factory with the buzzer deactivated.
Activation and deactivation
The activation/deactivation can be carried out only during the setting phase. Proceed as follows:
Switch off the appliance:
1. Push ON/OFF button
2. Push buttons PL2 and PL3 simultaneously
After some seconds, the buzzer emits a “beep” which indicates that it is activated.
To deactivate the buzzer, repeat the same operations till a “beep” is heard.
Buzzer signal
# A short “beep” is generated when a button is pushed.
# A longer “beep” is generated at the start of the programme or when the ON/OFF button is pressed to interrupt a drying cycle.
# Three “beeps” are generated at the end of a drying cycle.