bosch dishwasher not draining at end - E25 -repeated problem

[Katejon]

Can anyone suggest anything please
SMS69LO2GB/02 model

6 weeks ago - E25 error - water at bottom at programme end - blocked water pump message

Cure was – replace heat exchanger – the whole left side panel. Then worked perfectly. Engineer also said pump was fine. Been careful not to put very dirty dishes in there, so no chance of anything blocking –and the filter is very clean.

6 weeks later problem came back. Nothing had been touched by us. Emptied sump found a loose 12mm long screw in the bottom! Removed screw, tried it again – still flooded.

Goodness knows where the screw has come from but it isn’t blocking the impellor. I am not going to undo the clip in the sump as it wasn’t put back properly by me last time and… that is how the engineer last left it properly fixed – guarantees and all that – until next time I can speak to him.

But if anyone has the slightest clue as to what the devil is going on I am all ears as the problem has returned and the side panel cured it last time – which apparently is one of the main faults on these machines

many thanks

 

[zipper]

Emptied sump found a loose 12mm long screw in the bottom!

Did it have a T20 torx head?
If so look in the sump & check the impellor cover is in place, if not the pump will just cavitate & you'll get an E25 error.
If the cover is screwed in place remove it & check there isn't something jamming the impellor.

 

[Katejon]

ahh,,,, we now wonder if the screw may have from something else but how it got there is amazing. It has a 4 cross head - anyway it has been removed

the impeller cover is firmly fixed- as left by the engineer 6 weeks ago he replaced the matrix chamber and all has been well for 6 weeks - ( I put it back badly earlier and there was an E25 error from that then) .

We need to look again but... over the last 6 weeks have rinsed plates and been very careful so feel unlikely there is something jamming the impeller

it drains mid cycle - the pump works
the new matrix chamber 'seemed' to be the cure (but can't think why)
it is faulty on several programmes
occasionally... it does the cycle and drains at the end!

this is a mystery! having exhausted the internet for clues

 

[zipper]

I take it the engineer changed out the heat exchanger either because of a blockage or the reed switch was dippy.
Did he clean out the transfer hose from the sump to heat exchanger? Have you checked the sink spigot & waste hose for blockages?