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Service Manual UK
Indesit
Company
English
OKO Ball Detergent Recovery System
Linear Pressure Switch
The linear pressure switch uses a composite sleeve attached to an internal diaphragm that moves
through a coil as the machine fills or empties, when a current is applied to the coil a given frequency is
generated depending on the position of the sleeve, this frequency is readable by the main module.
On the basis of the information provided by the pressure switch, the module is able to calculate not
only the empty / full condition but exactly how much water is in the tub.
Switch operating parameters: 10.7 Hz approximately (empty) and 9.5 Hz approximately (full).
NOTES:
1.
It is recommended that the appliance is not tilted > 45° to gain access to the underneath of the
appliance if water is present in the drum as this may also effect the water level readings.
2.
If after any repair to the appliance the machine has been tilted >45° i.e. Tank change - pump/
sump hose inspection -Pressure switch hose disconnection, or the Pressure switch has been
replaced the pressure switch must be re-set to zero level.
3.
To achieve a zero level reading on the pressure switch manually drain all water from the appliance
via the drain hose by lowering it into a suitable receptacle, disconnect and re-connect the
pressure switch hose, this will allow the switch to zero calibrate.
Internally the switch comprises of a coil and small
printed circuit board, a composite sleeve attached to
the diaphragm and two springs.
Unlike a conventional bellows type pressure switch
that has fixed level open and closed contacts the
linear type operates by way of a variable frequency.
The OKO ball is placed
in the sump hose
