Water Level Switch; Water Control System - Intake - Miele W1903 User Manual

W1900 Series Clothes Washers
4.6

Water Level Switch

The Water Level Switch monitors the water level inside the drum.
The switch operates by closing specific electrical contacts depending on
the amount of pressure against its internal diaphragm. As the water level
inside the drum increases, the pressure against the switch also increases.
The changes in the switching are monitored by the Electronic and are
used to calculate the exact water level inside the appliance. This design
offers the benefit of keeping the water level consistent, regardless of the
absorption rate of the laundry.
Figure 4-3: Increased in water volume = increased pressure against the Level
Switch.
Note:
On the W1966 and W1986 model clothes washers, the Water Level
Switch is incorporated into the Control Electronic.
During the heating stage of the wash program the Water Level Switch is
used by the Electronic System to ensure water is present before the
heating circuit is activated. In addition the circuit is monitored for any
changes in pressure. Sudden changes in pressure usually indicate an
oversudsing condition. The Electronic System then automatically
performs the necessary adjustments to rectify the condition.
4.7 Water Control System – Intake
During the initial water intake, the Electronic monitors the duration of time
until the Water Level Switch is actuated. This value is used so that certain
wash variables (i.e. wash time, number of rinses) can be controlled during
the program.
If water level 1 is not reached within the programmed "water intake time"
(2 or 4 minutes), the Inlet Valves are closed; the program is cancelled and
the Drain Pump is operated for 90 seconds.
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Technical Information