Dishwasher (Miele G638 plus) on the blink: gets to the
pump-out part of the cycle and sits running the drain pump
indefinitely (when I got to it this morning it was flashing
the "drain/inlet" warning light). It fills and empties out,
but it doesn't stop pumping when empty. I checked the
obvious bits (drain hose, non-return valve etc) but nothing
showed.

So now I've got the covers off and have extracted a thing
that I'd expect to be a pressure switch,
<http://www.cyberpieces.com/devis/pieces-detachees-lavage-sechage-g636-0.htm>
has an image of something with the same part number.

My questions are:

* is it actually just a pressure switch (on/off), or have
these things got more sophisticated since I last fiddled?

* would one expect to be able switch it by blowing into it?
I've tried, and while something clearly moves inside,
there's no click, and the resistance between pairs of
terminals remains the same (infinite for most pin
combinations, short circuit for one). This fits with my
hypothesis that it's running the pump until the pressure
switch says it's empty, and that never happens, but I
can't see how to refute it.

* given that it appears to have adjusting screws (one is
visible in the centre of the image at the above link, the
other is in the tube at the very front of the picture),
can I simply fit a replacement, or will I have to adjust
it up to fill to the right level? I don't have a service
manual, so I don't know the procedure.

For completeness: the numbers printed in black round the
plastic part are 276974 E-01/09 T.NR.5380960 1200/700 and
embossed in the plastic are "Type 790", "83067", "8.8169",
"μ", "T85", and the terminals are numbered 12, 14, 11 and
the two gaps where terminals might be are both numbered 16.
I'm sure that's more info than could possibly be of use!

On-line spare parts suppliers in the UK don't seem to do
that exact part, but several offer
<http://www.partmaster.co.uk/cgi-bin/...80&query=Miele G640&model=G640&path=67231,108720:128251>
which looks very similar, but for a more recent model, so
I'll probably have to phone Miele on Monday.

Thanks,

--
Jón Fairbairn (E-Mail Removed)
http://www.chaos.org.uk/~jf/Stuff-I-dont-want.html (updated 2009-01-31)

"Jon Fairbairn" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
>
> Dishwasher (Miele G638 plus) on the blink: gets to the
> pump-out part of the cycle and sits running the drain pump
> indefinitely (when I got to it this morning it was flashing
> the "drain/inlet" warning light). It fills and empties out,
> but it doesn't stop pumping when empty. I checked the
> obvious bits (drain hose, non-return valve etc) but nothing
> showed.
>
> So now I've got the covers off and have extracted a thing
> that I'd expect to be a pressure switch,
> <http://www.cyberpieces.com/devis/pieces-detachees-lavage-sechage-g636-0.htm>
> has an image of something with the same part number.
>
> My questions are:
>
> * is it actually just a pressure switch (on/off), or have
> these things got more sophisticated since I last fiddled?
>
> * would one expect to be able switch it by blowing into it?
> I've tried, and while something clearly moves inside,
> there's no click, and the resistance between pairs of
> terminals remains the same (infinite for most pin
> combinations, short circuit for one). This fits with my
> hypothesis that it's running the pump until the pressure
> switch says it's empty, and that never happens, but I
> can't see how to refute it.
>
> * given that it appears to have adjusting screws (one is
> visible in the centre of the image at the above link, the
> other is in the tube at the very front of the picture),
> can I simply fit a replacement, or will I have to adjust
> it up to fill to the right level? I don't have a service
> manual, so I don't know the procedure.
>
> For completeness: the numbers printed in black round the
> plastic part are 276974 E-01/09 T.NR.5380960 1200/700 and
> embossed in the plastic are "Type 790", "83067", "8.8169",
> "?", "T85", and the terminals are numbered 12, 14, 11 and
> the two gaps where terminals might be are both numbered 16.
> I'm sure that's more info than could possibly be of use!
>
> On-line spare parts suppliers in the UK don't seem to do
> that exact part, but several offer
> <http://www.partmaster.co.uk/cgi-bin/...80&query=Miele
> G640&model=G640&path=67231,108720:128251>
> which looks very similar, but for a more recent model, so
> I'll probably have to phone Miele on Monday.
>
> Thanks,
>
> --
> Jón Fairbairn (E-Mail Removed)
> http://www.chaos.org.uk/~jf/Stuff-I-dont-want.html (updated 2009-01-31)

You will probably get threatened to keep quiet! Some folks on this group
will be mortified that a Miele has a fault - they always claim they are
perfect.

Jon Fairbairn wrote on 21/03/2009 :

> So now I've got the covers off and have extracted a thing
> that I'd expect to be a pressure switch,
> <http://www.cyberpieces.com/devis/pieces-detachees-lavage-sechage-g636-0.htm>
> has an image of something with the same part number.
>
> My questions are:
>
> * is it actually just a pressure switch (on/off), or have
> these things got more sophisticated since I last fiddled?
>
> * would one expect to be able switch it by blowing into it?
> I've tried, and while something clearly moves inside,
> there's no click, and the resistance between pairs of
> terminals remains the same (infinite for most pin
> combinations, short circuit for one). This fits with my
> hypothesis that it's running the pump until the pressure
> switch says it's empty, and that never happens, but I
> can't see how to refute it.
>
> * given that it appears to have adjusting screws (one is
> visible in the centre of the image at the above link, the
> other is in the tube at the very front of the picture),
> can I simply fit a replacement, or will I have to adjust
> it up to fill to the right level? I don't have a service
> manual, so I don't know the procedure.

That is just a pressure switch.

All those I have come across click when you suck/blow down the pipe,
though I suppose they might have conceivably have changed to a
capacitance type. Check the pipe is clear, they do block up other than
than it would be safe bet to get a replacement switch.

--
Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk

Harry Bloomfield <(E-Mail Removed)> writes:

> Jon Fairbairn wrote on 21/03/2009 :
>
>> So now I've got the covers off and have extracted a thing
>> that I'd expect to be a pressure switch,
>> <http://www.cyberpieces.com/devis/pieces-detachees-lavage-sechage-g636-0.htm>
>> has an image of something with the same part number.
>>
>> My questions are:
>>
>> * is it actually just a pressure switch (on/off), or have
>> these things got more sophisticated since I last fiddled?

> That is just a pressure switch.
>
> All those I have come across click when you suck/blow down
> the pipe, though I suppose they might have conceivably have
> changed to a capacitance type.

That was what I was wondering.

> Check the pipe is clear, they do block up other than than
> it would be safe bet to get a replacement switch.

I did that, and fitted it. (I didn't dare try blowing into
it). Machine still sat there whirring. Misery. Booked a
call-out, then suddenly thought that the pipes to the new
switch would be full of air, so poured in a few mugs of
water to give it something to chew on and tried again.
Machine ran. Cancelled call out. Happy again.

Thanks for the advice.

--
Jón Fairbairn (E-Mail Removed)
http://www.chaos.org.uk/~jf/Stuff-I-dont-want.html (updated 2009-01-31)