Bosch Dishwasher wont finish cycle

[pdrisc]

For some reason my Bosch Dishwasher has stopped working properly.

Main fault is that it will reach the end of the programme but not switch off as water flows in and the drain pump keeps attempting to drain the machines. Clean water will sit in the bottom of the machine

I looked at other posts in the forum and have attempted to fix following that.

I have cleaned the float valve and checked the impeller and non return valve but still no joy.

When the machine is running i can hear the drain pump kicking in and then there is clean water running through the matrix. As a result the water never gets a chance to heat up and the cycle persists.

The Matrix

Untitled

• pdrisc
• 26 Feb 2015
• 1

Float valve assembly

Untitled

• pdrisc
• 26 Feb 2015
• 1

There is one way to make the water stop flowing in by using the red rod in the picture to trip the switch and cut off the water inlet pump. Then the machine kicks in as normal. Not sure whether the water in the base of the machine is just not reaching sufficient height to cut off the incoming water pump. As soon as I release it it allows the inlet pump to kick back in and we get back into the same problem again.

There are no leaks in the machine.

Its a Bosch Exxcel model SGS43E08GB/43 FD8310

Heres hoping someone can help.[/img]

 

[yardie]

Check the switches on the fill float and pressure chamber in your 2nd photo.

P.s. also clean the gung out from the top valve shown at the very top of the pipe matrix in the 1st photo.

 

[pdrisc]

Thanks Yardie

Will try that later on.

Thinking about it again this morning (as you do) I reasoned that the reason that the float switch is not cutting out the water intake, is because there is waste water syphoning out of the machine through the drain pipe of the matrix. The valve at the top of the matrix is cycling and the water is flowing up and over the top of the upside down U.

Is there anything specific I have missed by not looking at the waste water side of the machine. I will check the non-return valve again in the sump at the bottom of the machine again as well.

 

[yardie]

If the waste water is simply feeding back into the machine ( getting past the valve at the very top of 1st photo, this prevents water syphoning back from the waste into the machine) then you simply need to check for a blockage in the waste hose that goes out to the 'sink'.
Also check 'U' bend, spigot etc...

That gunged valve will only cause problems later if not the issue now, so best to clean it whilst you have the chance!

 

[twiglet1]

Thanks for a really useful thread - even after all these years. Just wanted to add to what yardie said about cleaning that buildup from around that top valve. My washer was progressively cleaning worse and worse. It finally got to the point of trying a fix or invest in a new machine. Cleaning that valve was the primary cure.
To help anyone in the same boat, it's mainly fatty residue. I used 2 methods -after removing the matrix. First, turning the matrix upside down, filling the section with a hot sugar soap solution, l leaving to soak and then shaking vigorously. Then rinse and repeat. Probably did that about 20 times to get rid of 30 odd years if build up, including leaving it overnight soaking.
The other thing I did was immerse the corner of the matrix in an ultrasound bath whilst full of sugar soap.
IF you haven't got an ultrasound bath, the agitation got rid of much of it I would say.
Pics below show before/after.
I also cleaned the component with the float valve any pipes - but that valve seemed to make the biggest difference.

Matrix before/after pics below

Hope this helps