Bosch Dishwasher floods occasionally

[DIYinBerks]

Most of the time our Bosch Logixx (SGI6622GB) integrated dishwasher works perfectly; but once every few weeks it dumps a few litres of water on the floor. It fills up too high inside and then overflows the lip at the front, the water comes out just near the left hinge. Having overflowed about the same limited quantity of water each time, the flooding stops. This typically occurs with 32 minutes showing on the time remaining display, and it stays at this number with the dishwasher doing nothing. When we switch the machine off and back on again, it restarts at the beginning of the cycle and runs correctly - for the next 10-20 or more times before failing again in the same way.
Any suggestions how I should tackle this? Should I start replacing likely parts (and what might those be?) or are there some checks and measurements I could take next time it it floods? Any suggestions most welcome - buying a new machine as a last resort!

 

[cakeman]

might be a faulty pressure switch
might be gunge and similar building up
give the machine about 15 litres of very hot water and a few drops of bleach
let soak overnight
then switch on and run a hot cycle
should clean the insides out

see what happens then

 

[DIYinBerks]

Gunge build up sounds very plausible. We usually use the Eco 50 degrees program and I am not sure we ever use the hot wash. We'll try tonight. It might be some time before we know that it worked, but I will let you know in due course.

 

[cakeman]

that makes me more confident of my diagnosis

eco washes & quick washes on dishwashers & washing machines are good for efficiency but not so good for hygiene long term

 

[DIYinBerks]

Thanks again Cakeman - not seen the problem for a month now so we are gaining confidence that the soak and hot wash was the solution. We still use the ECO program mostly but try and do one 70 degree wash every week or so - hopefully that helps.