I have not heard of this problem before and I've had Mieles a long time.

Just like everything else though- moving parts fail sometimes, or suppliers send a bad batch of a compound or Rolf had a headache and his mom was about to die from cancer on the day he installed your valve and he didn't seat it properly.

S%*T happens - even on well designed, highly scrutinized top shelf manufactured product. Even the Japanese can't Kaizen 100% of defects and early failures out of a product. Now, if 3 more people here have this same problem this year, and a dozen next have the same - Miele will be taken off the high and mighty list and placed down in the gutter with the likes of Hotpoint and Magic Chef.

fauguy, thanks so much for writing this up. We're installing a Diamante right now. If at some point down the road I should hear rattling I'll check the non return valve. Appreciate your taking the time to give us the benefit of your experience with this.

BTW off topic, your posts long ago on getting a Blue Star to replace your former Viking were extremely helpful to me. And now I have a Blue Star.

Thanks again!

In the Miele user manual, it says that you should periodically clean out the bottom filter (which is easy to do) and also remove the non-return valve to make sure no food particles are inside it by rinsing it out (there's a metal ball in there). On average, I remove the bottom filter once a week, and hardly ever find anything in there. The non-return valve I removed about once a month, and never had anything in their either. So it might be that since I've taken out and replaced back the non-return valve about 10-12 times in the 10 months we've owned the unit, that it wore out the rubber o-ring on the side. Or that it could have been defective, or the seal just started to go bad. Who knows.

Now that I've had the new one in there for 2 days, it fixed that rattling/squeaking sound I was hearing when the water drained, which I believe was the rubber o-ring not forming a good enough seal, so that when the water was draining out, the suction was causing this sound.

I will not be taking this new non-return valve out at all, unless it starts with that noise again. And I would advise everyone else to leave yours in there and not take it out unless the water is not draining and there might be something stuck in the non-return valve that is blocking the water path.

sayde, that must of been someone else talking about a Blue Star and Viking, as I've never owed either brand, but glad someone was able to help you out. I've head complaints about Viking, as some of their products are made by other companies and just put the Viking logo on it.

Fantastic fauguy you focused on finding a fix and found it.

Is this the valve that prevents backflow?
"Non-return valve" sounds like it.
"...not take it out unless the water is not draining and there might be something stuck in the non-return valve that is blocking the water path..."

In recent years several posts made by GW members said that one did not need to install an air gap in the DW drain line with a Miele DW because Mieles had an anti backflow valve. When I pushed back against this point they posted resistance. Then, they disappeared or stopped insisting. But their writings are still in the archives.

Thank you for describing your situation. Persistence pays off.

p.s.

In http://ths.gardenweb.com/forums/load/appl/msg1216384729721.html
"Dishwasher with integrated air gap / one-way valve" there is a discussion about the valve

In http://ths.gardenweb.com/forums/load/appl/msg021329308697.html
the photo from Feb 9 illustrates what not to do, with the drain hose, and
a post from me about death and dying from diseases dragged in by drains.

Here is a link that might be useful: Feb 9: gray hose illustrates what not to do and why.

From what I understand, the non-return valve has a internal weighted metal ball, that when the water is drianed out, the suctions opens the space by lifting the metal ball for the walter to drain out. Then when it's done draining, the metal ball fall back into place, where you can see an internal black rubber seal. But on the side, where it connects to the dishwasher, there is a cream colored rubber o-ring that should have a tight seal. This is what I think went bad on the original part, as the new non-return valve isn't making this rattling/suction sound. But the installers also did the "High Loop" with the water drain hose before it connected to the disposal under the sink.
I haven't had any water back-flow from the sink into the dishwasher, nor have I had any bad smells that others have reported (not many with Miele, but have read some about it with Bosch). In fact, about 2 months ago out kitchen sink was completely clogged up, and the liquid plumber didn't clear it, so had to have a plumber service come and snake the main sink drain access line form outside. Even them, nothing got back-ed up from the sink line into the dishwasher.

Hi Fauguy, sorry that was Tyguy. But thank you for the Miele problem description!!!!

Thank you for the great info for both fixes. Mine is silent.

Sayde....ya that post was a couple of years ago now. I am glad my post influenced someone. For the record, I am still enjoying my Bluestar. I hope you are too.

Please note however, I am not a brand loyal person, so if I were buying a new range today, a CC would be on the shortlist, as would Bluestar. If there is any substance to the posts about the new open burner American ranges, they look pretty promising too.

Well about 2 weeks now after installing the new non-return valve, the rattling problem has started up again. I first noticed it earlier in the week. I had the unit set to the Pots/Pans mode, and it was silent on the first pre-wash drain, and also on the main wash drain, but then heard the rattling some on the first rinse drain and final rinse drain.

Over the past few days, it has continued doing it.

I (once again) have tested it, by removing the bottom spray arm and filter, let the unit fill with water some, and then drain it with the door open. I can hear, and feel with my hand, the rattling sound coming from that non-return valve. When I put my hand on it, I can feel it vibrating, and if I push down hard, it will stop some. It does not feel loose at all, and I even took it out and out it back in. It feels secure in there, but you feel the rattling when it drains.

So at this point I'm not sure why it is doing it again here. The original part was fine since last May, and started doing it last month. Then this replacement part was OK for 2 weeks, and is now doing it again too.

Is there any possibilities that could be causing this? I hate to have a tech come out, and have him say "oh this is normal" and leave, when I know it isn't, as it wasn't doing this for 10 months.

I'm going up to the Miele store this week for some detergent tabs, so I'm going to bring the part and tell them about it too.

Even though the rattling only occurs during the drain cycle, it is quite loud, and I can hear it all the way into the living room "L shaped". I hate to think that I'll just have to "put up" with it forever on a unit that cost $1600 (installed).

I'm thinking you have something in the circ. system. Did you check to see that all of the fins on the wheel below that ball valve are all intact?

If something is in there it could be a bear to get out.

Yes, every time I have removed the original non-return vulvae, and it's replacement, I have checked to make sure there was nothing down where the plastic blades are.
I've even took a turkey baster and suctioned out all the water in that lower area, then used a towel to get the rest out, and let it completely dry-out all day. Get a flashlight and look in there to make sure there's no particles at all, as well as rinsing out the non-return valve.

But tonight it did the same rattling sound again.
It's the smallest pain the the a-- that is making such a noticeable sound.

Like I said before, it only does it when it drains, and then about 50-60% of the time. But when I place my fingers on the non-return valve, I can feel it vibrating when it makes that sound. When it doesn't make that sound, I can't feel it vibrating.

So that's why I'm thinking it's either not staying as secure in-place as it should, and over time get's a little loose and starts to rattle when draining. Or its that internal metal ball that's rattling around. Or the plastic blades underneath that are hitting it.

At this point, I can't say for sure what the root cause of the problem is, only that I know that it took 10 months before it started to do this. I replaced the non-return valve, was OK for a couple weeks, and has started back up again.

One thing that I've forgot to mention...
Sometimes when I hear this rattling sound while its draining, I will light up on the handle/latch on the front of the door, which will stop it from draining. Wait a few seconds, and then release the hinge latch for it to continue draining, but the rattling sound would be gone.
Weird, I know, why stopping and the re-starting the drain mid-cycle will stop the rattling sound.

I had a friend of mine over today, which has a degree in aircraft/turbine/powerplant, and I showed him the problem I was having. He heard the sound, and said to him is sounded like a rattling, or an old squeaky door hinge. We both looked at the (new) non-return valve that I got earlier in the month and the older one that came with the dishwasher.

After talking about it some, we wondered what would happen if that metal ball was not in there, would it still make that sound or not.

So we took the older non-return valve and opened it up (it's two pieces of plastic stuck together), and inside was the metal ball and a black rubber seal that the ball would "fall" on so that water would not come back in to the unit from the drain line.

We took the ball out, left the rubber piece in there, and put the two plastic parts back together. We then ran the unit with the door open, just to it would fill with water, and then drain, and there was no rattling sound. But we did see a small amount of water come back in, since that ball was not in-place to stop it. So we closed the door and ran it through the Express Mode (start to finish) 4 times, which was an hour total with 12 fills and drains, and still no rattling sound.

So we then took that non-return valve out (which is the one we removed the metal ball from) and put the new non-return valve back in (that I got a few weeks ago) Ran the Express mode. The first drain it was silent, but then on the two drains after that it made the rattling sound. So we then ran is again. This time all three drains it made the sound.

Again, we took that non-return valve out, and put back in the one without the metal ball. Ran the Express mode, no rattling sound.

So after fooling with it for about 2 hours, it seems that the cause is the metal ball located inside the non-return valve. Sometimes when it drains, that ball is moving/vibrating around inside there, which is causing the rattling sound. With the metal ball removed, the sound is gone.

The question still is, why did it start doing this with the original non-return valve until 10 months after owning the unit. Then when I replaced that part, it was fine for 2 weeks and then started again. When I go and get the dishwasher tabs from the Miele store next week, I going to bring both non-return valves with me and explain to them the situation. See if anyone there or a tech may know what is going on, but it would probably take a service guy here to see if he can find out why it's doing this.

Went up to the Miele showroom and purchased the tabs and salt a few days ago, and brought with me the two non-return valves. I explained the problem to the guy there, how there is a rattling sound sometimes when it drains the water, but when I use the non-return valve that has the metal ball removed, it's silent. He said this was a first for him to hear of this problem, but since he is on the sales-side, not tech-side, he said that a tech really should come out and take a look. That it could be sometime as simple as the unit not being perfectly level, so when that metal ball is forced up, it could be tilted some to the side, and causing this rattling sound.

I just think its weird that it was fine for 10 months and then started this. Replaced the valve, fine for 2 weeks and then started again.

So next week I'll call and schedule a tech to come out and see if he can identify the problem and hopefully fix it.

Hiya Fauguy
Just wondering about the diameter of the drain stem on the dishwasher tailpiece under your sink. I'm suspecting that a combination of back pressure and drain hose flexing may be causing a pressure wave to travel up and down your drain hose. This would probably make the ball rattle up and down a bit. Remember that the ball checks against the black rubber gasket, not against the discharge side. There's a small rib inside there to prevent the ball from going up against the output tube.
So try this - disconnect the drain hose and aim it into a 5 gallon bucket. (only 1.2 gal per fill) and let it fill and drain a few times. Let's see if the rattle goes away!
-P

The drain hose is connected to a standard KitchenAid 3/4HP disposal unit under the sink. The hose does the standard "high loop" which is said to prevent anything from the sink to back-fill in the dishwasher, which is what the installer told me.

Everything is how it was when the Miele Certified installer (New York Minute) installed the unit last summer.

I really don't want to try this on my own, as I paid $1400 for the unit and $150 for installation, so I'd rather have the Miele tech come out. But I understand your point, and I've thought the same thing...that maybe there some type of pressure in the drain line, that is causing the ball to vibrate inside the non-return valve while draining the water.

Like I said in my earlier posts, on the non-return valve that I opened up and removed the metal ball, it solved the rattling noise, but does back-flow about 1/2" of water into the sump area (as that ball is not in place to stop the water from returning). It's really not that much.

So at until the Miele tech can come out, its either use the non-return valve with the metal ball in there that rattles when draining, or use the one without the ball that is silent, but has a little bit of water return back into the bottom sump area.

Called Miele and we tried a few things over the phone, but still doing the rattling sound. They had the option of sending out a "Authorized Servicer" sooner, but since I wanted their own Miele tech to come out, I'll have to wait about 12 days.

Hopefully they will be able to find the source of the problem.

The Miele Tech came out this week, and said this rattling sound is "normal" as water passes through the non-return valve and moves the metal ball around. He said that he hears it on his own Miele dishwasher at his house, and also on other units he's serviced, though I'm the only one who has called in about it that he knows of.

He said there really isn't anything that he can do to "fix" it, other than ordering another non-return valve, which I should get next week (and change out myself). He said that he's heard ones that are ten-times louder, and orders those people a replacement part as well.

I told him that the original one was fine for 10 months, and then started this rattling in Feb, got so loud that by March I had to have one sent out. It was OK for about a week, and then started to make the rattling sound, though not as loud.

He said that there's really nothing else that can be done, just hope the replacement part is OK, but if it does rattle, you just have to live with it.

This sounds pretty stupid and pathetic to me, that a $1400 dishwasher (+ $250 for the 4-year extended warranty), that they can't get this non-return valve to not make rattling sound when draining water - and it was fine for the first 10 months?

When I get the part next week, I'll install it and see if it sounds OK or not. If it makes the same sound, should I call Miele back, complain, and tell them I want t different Tech to come out?
What do you guys think?

And the saga continues....

After the service tech came out last week and said the rattling sound from the non-return valve is "normal" and ordered me a new one, I called Miele service in NJ and talked to them about. The guy put me on hold for several minutes so he could ask other people there about it, and came back saying that it should not be doing this rattling sound. He said that once I get the new non-return valve the tech ordered, for me to go on in install it, but he scheduled me for a new service call next month with a different person (but still a Miele tech) as I told them that the guy that came out last week seemed to have a attitude. They are going to send this other tech another non-return valve and a pump for the unit, as he said the pump is really the only other moving part that is involved with the drainage.

On Tuesday I recieved the new non-return valve that was ordered by the tech last week. I took the old one out, and use the turkey baster to suction all the water out, and used a towel to make sure it as all dry. Once again I got a flashlight and looked down there where the propeller blades are to make sure there was nothing "stuck" in the area, but like before there wasn't any particles there.

I installed the new (now the 2nd) non-return valve and tried the dishwasher on the express cycle. It did 3 fills and drains, all with non rattling sound. About 2 hours later I tried it again, the first drain was silent, but the two following drains did make the rattling sound. That night I ran the Normal wash mode, and once again it was rattling on all 4 of the drains. Wednesday night I ran the Pots/Pans mode, and the first two drains it was silent, but the two final rinse drains it rattled. So as of now it's back to doing the same time it was before.

I guess at this point all I can do is wait for the different Miele tech to come out in a few weeks and see what he thinks of it - if he says its "normal" or not. I still find it weird that from the end of April last year when the dishwasher was installed, until Feb of this year, it was silent, then started the rattling in the non-return valve. It's been replaced twice now, and it hasn't solved the issue. The only way for it not to rattle is to use the one where I removed the metal ball from, as it is silent when it drains. The only bad part is that the ball is not it place to prevent some drain water from returning back into the bottom sump area.

At least I did purchase the 4-year extended Miele warranty ($250).

It's been 3 weeks since the 1st Miele tech came out and said the rattling noise was normal when draining. This week a different Miele tech came out. He also said it was pretty normal for it to do it while draining, with the metal ball vibrating around in the non-return valve.

He was here about 90 minutes, change out the non-return valve (again) and opened the bottom area to replace the drain pump (with the plastic propeller attached). Also cleaned out the drain line.

When he was done, we ran the unit, and when it drained it still did the rattling some, but it seemed not as loud now. Hopefully it resolves the problem.

Thanks for this post.

My Miele started to make lots of noise. Asked my husband to look at the drain pump and clean out the impeller area. He said that something was catching the impeller.

Well I started to look inside the non-return valve and lo-and-behold, there is a tiny plastic thingy that came off of one of my kitchen appliance. I also ran the dishwasher with the non-return valve out. The impeller also spit out another of the plastic thingy.

It does not matter what it was. The instruction was invaluable!

Thanks all!!!

Can anyone tell me how to remove a stubborn non-return valve? There is a plastic pin (locking clamp? But I don't see how it locks anything in) that I have to tilt to the side and pull out the valve. The valve will not budge.

Once you remove the screens exposing the sump you"ll see the housing of the impeller.

It is plastic and has a METAL wire retaining clip over the top of it locking it in place. The wire un hinges off of it and rotates out of the way. Now you grab the top of the valve and rock, wiggle, and pull upward to remove the valve exposing the impeller. The housing can put up some resistance especially if the unit has some age on it or has never been removed. There also seems to be a bit of a vacuum on it, resisting removal.

I believe all of this is in the owners manual with a picture.

I have been using Miele dishwashers for 15 years and the quality has trended consistently downward. New house to us 2 years ago and we bought a G5105 U. Fifth of the brand I have used at work/home. Cleaning effectiveness isn't nearly as effective on the present model and the middle basket is rusting hand-over-fist in five different places. Older models were invincible.

Surprising particularly because the dishwasher environment is aggressively corrosive on cheap steel. Engineers can either protect vulnerable surfaces or use high grade stainless steel. Neither happened here.

Miele technical service department's answer is to sell me a new basket. Zero response to the pictures I emailed their office.

If you have a show kitchen where no real work happens it will probably work out. But my wife and I cook often routinely running the dishwasher two times a day and this model is not up to the job.

We have lost trust in the machine checking each item closely as it is unloaded. Upper silverware rack is a particular weak point. Breaks your focus in the kitchen. Gratuitously hand washing a pile of things hot from the washer makes you feel like a rube.

thanks for the info! my diamante plus was rattling too when draining - just started after 5 years of silent service. took the bits apart, cleaned them and checked the seals, spun the impeller, fished out an olive pit and a piece of hard clear plastic, and put it all back together again. Glad that's all it took. Watching this youtube video also gave me the confidence to take it apart and get my fingers in there: https://www.youtube.com/watch?v=_oQwa-0lQk4

Great posts from fauguy. Had same issue - but found that the non return valve is made up of two outer pieces, the inner rubber seal and the ballbearing. Discovered that the head of water was causing the two outer case parts to blow apart so water not going up the drain pipe. The washer is 8 years old and the sealing glue had failed. The noise is the pump impeller cavitating. Removed valve, cleaned and dried it and used araldite 2 pack glue around the edges of the components. After several hours curing, put it all back and it is now sorted. To test your valve casing, just try gently pulling it apart. If it breaks open easily, this is your problem too....

I had the same issue with my Miele G 6160 SCVi. We noticed an unusual rattling sound coming from the dishwasher, then after a few weeks it kept cutting out with an F11 error after a few minutes. I cleaned out all the filters and played around with the non return valve as well, but to no avail. It become apparent that the rattling sound was in fact the metal ball in the non return valve bouncing around. But the non return valve sound was a symptom, not the cause. The cause was in fact very straightforward, just a blocked drain. The dishwasher outlet hose is connected to small connection on the sink p-trap. These usually protrude at a 45 degree angle from the p-trap, and have quite small inner diameter no more than about 15mm. This connection was blocked with grease and debris. After cleaning that out, the dishwasher now works fine again and the rattling sound has gone.

So if you have this problem, and a similar drain connection, disconnect the drain hose from the sink and poke something down the sink connection to make sure it is not blocked, before taking other steps...

Unfortunately ,i am hearing some rattling noise as the water entered and exited the cycle...I have cleaned everything out and still no change.I am going to contact Miele to order a new return valve and hopefully i have the same result as you.After i make the switch i will be sure to circle back and inform the board