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Indesit Company
Service Manual UK English
Controls Overview
The user controls consist of a programme selection knob, option buttons and a Start/Pause button.
The control system consists of a user interface and control module, a thermistor mounted at the top of
the front air duct and one mounted on the heater assembly and a conductivity sensor.
The conductivity sensor is mounted in the front air
duct.
A single wire connects the sensor to the control
module.
The thermistors and conductivity sensor send values
back to the control module. The control module then
determines the programme duration and required
dryness of the load in a set of values for a particular
programme held within the control module software.
The combined Control and Power Module is a single
unit located at the top front right hand side of the dryer directly behind the console panel.
This module does not have a standard service port, and requires the use of a Low End Adaptor to
connect the Hardware Key to permit module programming.
The control module must be programmed with the relevant eeprom file if the control module is
replaced, the eeprom file becomes corrupted or if an updated file becomes available.
Programme Duration:
Once the programme has started the module will determine programme length for the size and type of
load. This detection is made within 10 minutes of the start of the programme and is achieved by use of
the front thermistor, rear thermistor and conductivity sensor. The module will then adjust the
programme time accordingly.
If the clothes are not sensed as dry when the 10 minute Cool Tumble period is reached, the module
does not start the Cool Tumble but continues to dry the clothes until the value from the conductivity
sensor indicates that the clothes are dry. The programme then advances into Cool Tumble.
Maximum Programme Period:
If after the maximum permitted programme time of 300 minutes (Note: this is an internal default value.)
the clothes are still not sensed as dry, the programme advances to Cool Tumble and completes the
programme. No fault is indicated if this occurs.
Heater Control
The control module also controls the heater. This has an upper and lower element. The lower (static)
element is permanently energised (except in cool tumble) and the upper element (dynamic) is cycled
on and off by the control module during a programme to maintain the correct temperature within the
drum for the programme selected.
If the user turns off the power or disconnects the mains cable or there is a power cut, the dryer will
remember its last settings and resume the programme when the start button is pressed.
If the event of a controls or thermistor failure, a cycling thermostat and one-shot thermostat are fitted
as safety devices.
Bearing Pads
Conductivity
Sensing Strip
Drum Support Wheels