Bosch Washing machine is overfilling
A fault with the water inlet valve
The water inlet valve allows water to enter the
washing machine drum, and if there is a problem with the washing machine overfilling, this can be caused by a faulty water inlet valve. This is not a fault that you can repair yourself and will require a repair by a trained and qualified plumber.
A fault with the pressure switch
The pressure switch, or water level switch, is responsible for sending signals to the water inlet valve to control the flow of hot and cold water into the washing machine according to the temperature setting for a particular programme. If there is a fault with this switch, this can cause the washing machine to overfill. This is not a fault that you can repair yourself and will require a repair by a trained and qualified Bosch engineer.
A fault with the pressure chamber
The pressure chamber fills up with air by the rising level of water in the drum. This air is then pushed up the pressure hose and activates the pressure switch to commence the wash cycle. If there is a problem with the pressure chamber, such as a blockage, this will interfere with this process and could cause the washing machine to overfill. This is not a fault that you can repair yourself and will require a repair by a trained and qualified Bosch engineer.
This advice is from the Bosch website so they will say that a qualified engineer is required. But to be honest if it is any of those faults then you will need an engineer. I would think it's the pressure switch or the pressure chamber not filling. That could be caused by a blocked nozzle but you would have to find the nozzle that fills the pressure chamber.
