Bosch dishwasher filling problem

[Roland Perry]

In message , at 21:28:39 on Sat, 29 Nov 2014, Rod Speed remarked:

The reason it has very little water pressure is because it has very little WATER. The pump is trying to circulate the dregs in the sump, and the result is only a dribble getting as far as the rotating arm at the top of the washer.

It's two different scenarios. One is a slight leak which the floating detector picks up and stops it filling at the start of a cycle. The other is (eg) a hose splitting mid wash.

That's right - he hasn't got a catastrophic leak.

[Snip lots of stuff that's completely misunderstood the failure symptoms].

See above, it's not a multi-pressure pump, but the regular pump having nothing very much to pump.

To avoid pouring water into a washing machine with a leak. I'd prefer it to give a visible/audible error indication, but that's not how it works.

If the user then subverts the system by pouring a couple of pans-full of water in by hand, it carries on (with some water available to pump now) and completes the rinses too.

Nope, that's all completely correct.

What do YOU call the thing with salt in it?

It doesn't carry on regardless, you have to put water in by hand.

What do YOU call the part of the washer that comprises the floor and the frame which holds the rest of it up?

The leak detector is for small leaks. In my washer there was about half a cup-full in the float-compartment when I first started debugging it.

I know. You've made that bit up.

I know, and it's that symptom which I've been explaining.

[Roland Perry]

In message , at 09:55:32 on Mon, 1 Dec

2014, Rod Speed remarked:

Yes, that's exactly what's going on, because the only water in the sump is that left over from the last wash.

I've observed it many times, while experimenting with my 'broken' washer.

It's easy; you open the door a crack and can see how much water is splashing around. And it sounds quite different too - the pump is quite clearly "gasping" for water, rather than there being a "sloshing around" noise.

Where is it then? On my washer's control panel there's only one light, called "End"; plus the lights in the four different programme buttons which merely say which one you've selected).

As you've been told several times now, the washing cycle commences with no more water in it than was left from the previous wash.

Over to you...

There's me and the OP. And doing online searches the only solution people offered was that the inlet valve was faulty. But if that's the case, it wouldn't operate properly to fill with rinse water. And I took it out and tested it, and it was working OK.

It could, because the outlet pipe is about two inches under water while it's washing. The exhaust pump is a very simple centrifugal one (the same as on clothes washers), and if you took off the output pipe, water would flow through it by gravity.

Mine doesn't have one.

Bully for you.

I don't need to measure it, I can clearly see that no water is added by observing the transparent piping on the side of the washer.

Mine does (and apparently so does the OP's).

[Bob Eager]

So, it's a different model. My Bosch dishwasher has lights for water supply, salt and rinse aid.

[Roland Perry]

In message , at 17:56:42 on Mon, 1 Dec 2014, Bob Eager remarked:

Clearly. The problem is that Ron seems to think that because his a different model, mine isn't broken.

Previous washers of mine have had lights for salt and rinse aid.

[Roland Perry]

In message , at 07:47:20 on Tue, 2 Dec

2014, Rod Speed remarked:

The pump's unlikely to be damaged by running with a low water supply, and there is some water in the pump itself.

When this fault condition happens, it's fairly obvious because the dishes don't get washed. And when you stand next to it you can't hear the wash-water sloshing around.

It'll be heating the little water there is, and then turning off. It won't have enough intelligence in the controller to think "hmm, that heated up faster than normal".

Yes, that would be one way.

It's pumping the residual water in the sump. That's enough to produce a trickle from the rotating arm, but not enough to actually do any washing.

It didn't take long. As soon as it stopped washing the dishes properly I took some time to stand next to it after I'd started it (rather than leaving the kitchen) and it was obvious from the lack of "sloshing noise" that the water fill wasn't working.

For a few days I worked around this by opening it up when it had been running about a minute, and added water by hand.

Then I took a day off work and removed the dishwasher from under the counter, took the side off, and started debugging what was wrong with it. It was then that I found the flood detector, and saw it had some water under it.

Which is on the front of a different model!

It doesn't pump it all out, and as I've told you before there's the back-flow water that was in the uphill bit of the drain pipe.

What he described is the same as I observe. The residual water in the sump.

One online resource mentioned the flood detector, but in general the "help" sites are about as useful as people saying "re-install Windows" when anything goes wrong with your Windows PC.

Depends how serious a leak. It could be as little as a drip every ten seconds.

That's not the case. There's more than you imagine.

We won't make any progress if you continue to be in denial about the residual water.

ps. Still waiting to hear what name you give the water softener.

[Roland Perry]

In message , at 05:52:08 on Wed, 3 Dec

2014, Rod Speed remarked:

Wrong wrong wrong for the umpteenth time. There's enough residual water in the sump to do that.

I know that his symptoms are exactly the same as mine.

Are you yet in a position to suggest what we might do to fix the machines?

ps Still waiting for your name for the water softener.

[Roland Perry]

In message , at 06:22:43 on Wed, 3 Dec

2014, Rod Speed remarked:

That's what happens. I've tested it several times.

The drain pipe does up at least a foot and a half in most installations (to avoid siphoning effects). The water in that foot and a half falls back into the sump when the drain pump stops.

Sigh. The sump water.

You must ask them why this is what happens.

Two of us in this thread.

Not all of it.

It's very obvious when you look at the transparent inlet piping that it adds nothing at all.

Only that much water described above.

Only that much water described above.

Only that much water described above.

There is.

Have you actually looked??

They pump out as much as they can, but it's not all of it.

Without a non-return valve on the pipe, please explain how nothing flows back into the sump.

It's probably why they often do a "pre-rinse" as much to get the old water diluted and out as to remove the crud from the new load of washing.

The thing I did many times was observe the wash cycles having taken the thing apart.

It gets the dishes washed.

Not all of it.

That's part of the pre-wash thing.

It was in the drain pipe, but flows back through the pump when it stops,

But there's more in the sump than you acknowledge.

Indeed, that's because the pump isn't capable of draining the last pint or two. And it can't do it at the start of a new wash cycle any more that it could at the end of the previous one.

I suggest you take off the outflow pipe and see how wet your feet get.

But the models which the OP and I have don't have that function built in.

[Roland Perry]

In message , at 09:44:51 on Wed, 3 Dec

2014, Rod Speed remarked:

I don't think I'd use the word "stupid". In any event, it's impossible to pump every last bit out, so there will always be some in the bottom. That will mix with the drips from off the plates and with the first fill of pre-rinse water.

Could be a different fault with the same symptoms, but it's unlikely.

I've done the equivalent of that with mine. While I didn't turn off the water supply, the pipes in the side of the washer are transparent and it's completely obvious whether any fill water is flowing.

[Roland Perry]

In message , at 10:20:34 on Wed, 3 Dec

2014, Rod Speed remarked:

It's possible the inlet valve is intermittent, but if so it's very repeatedly intermittent. Not letting any water in for the first fill and working perfectly for subsequent ones.

Syphoning also depends where the drain is connected to at the sink end.

When the dishwasher finishes it pumps the sump out, but a small amount remains in the pipe.

When you restart the washer it has another go at pumping (why would it so that if the sump was guaranteed to be empty? But of course it can't pump out more than it did the previous time, so unless there's been a leak you won't see any additional water coming out of the drain pipe.

When it's finished the pre-pump, then that same pipeful of water falls back into the sump.

Another reason your experience differs is because you've said *your* drain pipe doesn't have an anti-syphoning hump in it.

The outflow pipe is attached to the exit from the sump. If you were operating the machine without that attached then all the drain water, even for the complete fills, will be pumped onto the ground directly underneath the washer. Is that what was happening?

Mine doesn't.

[Roland Perry]

In message , at 11:05:35 on Thu, 4 Dec

2014, Rod Speed remarked:

The drips off the new dirty plates you've been stacking in there.

So you've never taken the side off and looked. Quelle surprise.

[Roland Perry]

In message , at 11:29:25 on Thu, 4 Dec

2014, Rod Speed remarked:

The way the pipes are constructed it's completely obvious whether there's any water flowing in them or not.

In your installation. But most people have a different configuration which includes the anti-syphoning up-and-over.

No, the drainage from the main chamber to the sump is pretty much instantaneous. Water running downhill and all that.

That's one of the functions of the pre-rinse, but YOU insist the designers are stupid enough not to have that on every programme.

That's because it's *your* drain pipe that's doing this, and very few other people's.

They are neither dry (because there's enough water to dribble out of the rotating spray) nor would the technology used in the pump suffer if running dry (it's just a motor-driven impeller in a chamber, if the chamber's empty the motor has no load).

[Roland Perry]

In message , at 10:50:00 on Sun, 7 Dec

2014, Rod Speed remarked:

Only if the machine succeeds in letting water in. The fault under discussion is when it doesn't.

In which case perhaps you've forgotten that it's obvious, when looking at the transparent pipes inside, if any water is flowing?

[Roland Perry]

In message , at 11:04:45 on Sun, 7 Dec

2014, Rod Speed remarked:

But you've seen inside, apparently. So you should know that you can.

We aren't discussing your "on the concrete" installation, but if you think we are than it explains a lot.

What has that got to do with the dirty mixture in the sump after you've been loading a fresh set of plates to clean?

Yes, the first thing it does is pump out for at least four seconds. Then it ought to start filling. We are looking at the situation where it doesn't start to fill.

That's not the way it works.

I don't have a manual; the washer came with the house and the previous owner didn't hand over any manuals.

It's not dry, there's enough water in the sump to at least pup up a dribble as far as the top of the machine.

[Roland Perry]

In message , at 22:02:58 on Sun, 7 Dec

2014, Rod Speed remarked:

Do you mean pre-rinse? The one you said wasn't present in every programme?

Wrong, the fault stops the water entering.

No, because it flows through various up-and-over pipery, and if the level on the inlet side doesn't reach the top of that, nothing can flow into the washer.

[Roland Perry]

In message , at 22:17:14 on Sun, 7 Dec

2014, Rod Speed remarked:

Repeating all sorts of stuff we already discussed why you seem to be clueless about this situation.

[Roland Perry]

In message , at 07:55:31 on Wed, 10 Dec 2014, Rod Speed remarked:

How does a rinse after a wash, clean the next set of dirty plates you put in. Are you losing the plot??

I still claim that.

That's right, it rinses the plates which have just been washed.

Not the new set of dirty plates you put in after you've taken those out and stacked them in the sideboard.

What doesn't fall back?

[Roland Perry]

In message , at 07:27:58 on Thu, 11 Dec 2014, Rod Speed remarked:

Compare the two lines above.

You may not believe it but it's what mine does.

Except there's no leak as big as that, so the sump water does pump up as far as the rotating arms.

If it falls back at all, it's into the inlet, not output, side.

[Roland Perry]

In message , at 07:44:05 on Thu, 11 Dec 2014, Rod Speed remarked:

"My mother's old Bosch is playing up. On a normal wash it just doesn't seem to take on board enough water. If you chuck extra water in it seems to work fine but otherwise you can hear the pump running and if you yank the door open, you can just witness some feeble jets of water coming from the washing arms, too feebly to make them rotate."

The only credible reason is that it failed to put any new water in.

Except it doesn't in my case. Other dishwashers I've had might have done.

It's an SE64630GB manufactured by Bosch, branded by Siemens.

[Roland Perry]

In message , at 07:24:28 on Fri, 12 Dec 2014, Rod Speed remarked:

But I'm quite sure it's taking no water on board, because the exact same scenario played put on my dishwasher is the result of no additional water being added (just the dregs in the sump being pumped round).

It doesn't matter how many times you repeat your rebuttal, it's what is happening.

That's right. He's describing exactly the same as I do.

Two reasons why that's an incorrect diagnosis.

No, three:

I took the solenoid out and examined it. Not scaled up.

No water at all flows at the start of the cycle .

Plenty of water flows during the rinse cycles (as observed through the transparent tubes in the side of the washer, and also inside sloshing around).

I know you don't believe it. But it's true.

There's only one light, called "End".

That's a small bit of progress. At least you now accept there is a chassis and that it does have a leak detector.

[Roland Perry]

In message , at 13:35:49 on Sat, 13 Dec 2014, Rod Speed remarked:

Of course I do - I have watched the transparent pipes in the side of the washer (having removed the covers), and no water flows.

Unless you can answer that, I don't think you have any credibility.

[Snip: lots of blather than can wait until you answer the above]