2LYMPAIA - F4 - Whirlpool Dishwashers

Hello

If you have F4 and the sump is full of water, there's a good chance the drain pump is being jammed by a broken bit of glass or pottery. However, if the appliance is empty of water and F4 error code is flashing, where do you go from there?

The electronic control (module pcb) does a self check of the components, during a drain cycle the programme allows a time parameter for the appliance to empty away the water. How does the pcb know the water has gone? Simply by testing a pressure switch for continuity.

The pressure switch is an on or off switch, when the appliance is empty the internal contacts are "made" (on) when the appliance is full of water the switch is "broken" (off).

The sensing grid of the pressure switch is exposed to the dishwasher wash water and can over a period of time get clogged with crud ( a mixture of food waste and detergent and limescale), eventually this crud stops the switch from being in the correct attitude during the self tests. The electronics notes the on or off and determines that the appiiance has not drained and gives error code F4.

If you have F4 error code it could be the pressure switch needs cleaning or replacing.

On the self test about 4 mins is allowed for the appliance to empty the water away.