Run a dose (or more if necessary) of a dishwasher cleaner product, which are available at your local store with the dishwasher detergents.

Do you have hard water? The residue may be mineral deposits. Phosphates have long been removed from detergent formulas. The replacement ingredients aren't as efficient in handling hard water. Extra detergent dosage may be needed in cases of very hard water.

By the way, KUDE isn't a full KitchenAid model number. There should be numbers and more letters.

Sorry, dadoes -- you are so finicky about those numbers! It's hard for me to conceive of there being a difference, but I should have known you'd ask. It's, um, KUDE70FVSS0

I think the point is that the only way water leaves is through that super-fine strainer and obviously gunk gets left behind. I'm in LA and am unaware of especially hard water. But obviously something's just not dissolving.

I'll look for "dishwasher cleaner product". As a rule I use way less detergent than may be called for so I suppose it's possible I'm just not solubilizing what needs busting up.

LOL, I just wanted to look up the parts diagrams to confirm the pump mechanism type.

Can also use Lemishine to clean it but the dispenser cups don't really hold enough, you'd need to add a little more during the main wash period. The designated cleaning products may work better. Finish Dishwasher Cleaner and Glisten Dishwasher Magic, for example, are liquids in a bottle with a wax plug that melts when the water gets hot enough during the cycle.

Thank you! I have to make an amazon order anyway... Surprised there's no add for it in my sidebar here...

I get that stuff too. It's a weird substance. Do report back if whatever you used cleaned it. Or if you find out what it is. :)

Change of detergent may help. All detergents are not created equal. Different formulas react differently to local water conditions, whether hard or soft.

Hi - reporting back on what's turning out to be a totally non-trivial problem.

It took me awhile to locate some lemishine; basically it's expensive online because it's heavy, probably. And I find going to Target onerous, so ... Any cheap sources are appreciated!

And fyi lemishine (LS) appears to be citric acid hemihydrate . I imagine citric acid used for canning and the like is a good-enough substitution.

So there seem to be three versions of lemishine available online. I bought the "booster" in the green bottle.

The instructions said: "clean your machine first" but I didn't because of the testimonials online showing first or second-washing improvements. Mistake.

I ran a load with LS in the main bucket, my old Cascade in the rinse bucket (I hate hate hate to throw anything out so while I know the decrepit state of this detergent is a problem I cannot being myself to toss it out).

What seems to happen is, the caked-on minerals get loosened in clots. This machine has no food grinder, just a super-fine sieve so stuff gets loosened but cannot really leave easily. So this load was odd in that you could see stuff getting cleaner, a bit, on the machine's insides, but the cutlery especially was coated with a fine grey grime. Ick.

I left the dishes to soak and ran the machine empty. Again, there was some improvement in some of the inside spaces, but still it's all a mess. But the filter was interesting, with bits of grey lightweight schmutz. Ick-ola. I cleaned and scrubbed this and removed what I could from the water trap where more plaques were floating.

I re-ran the load and stuff was clean-enough to use I guess. I'm not fussy. But I then ran the machine again empty, this time with super-hot water. And then again empty with the power wash (cookware) cycle.

Every time I can see things getting cleaner inside but it's still not 'clean'. But you can see the grunge line moving downward on the door, for example. And the filter is always a little bit less disgusting.

Another load with dishes was still not beautiful, but you could start to see some glasses were starting to come clear. What happened in some cases was the film of grime would go away and reveal actual "dirt" underneath around where one's lips touch the glassware.

So another empty-load and another full one has the machine with just a faint residue of grunge on the bottom two inches or so of the door. The filter continues to emerge grunged and the water trap still has less "floaters". The sides of the water trap I can take my fingernail and release some plaques from. The glassware is starting to really look clear, some of it at least. I'm convinced this is because there's no food grinder and no good way to move the grunge out.

The gasket around the bottom filter is now, from several iterations back, black instead of caked-green-grey. That's nice! And it's got some give to it again.

The heater element is really interesting. It had been sort of nobbly with concretions. Those are gone now and last time it had a layer of orange-grey on it, this time the orange was gone leaving a dark grey smudge. I took a soft cloth to that this time and wiped it clean. It's a very tarry-substance but hand soap washes that from the cloth. I think it's lipid, just highly broken down. Ick again.

Actually, the floaters and this residue remind me of the foaming guck that floats on polluted water, the "natural" stuff. It's very lightweight but voluminous.

So .... getting there. Geez what a process. I like the quietness of this DW but I think if/when I need a new one, I'll opt for one with a grinder inside. And I think we need to be placing our dishes in there cleaner than they're going in now.

Nasty!

If the water is really this hard why isn't there a comparable buildup in the washing machine?

There was no mention in your initial post that dishware is also coated with residue. Sounds like a change of detergent is definitely in order. Perhaps the machine's heating element isn't working, causing too-low water temperature during course of a cycle. Poor wash performance can also be caused by insufficient fill level due to the inlet valve clogged with debris from the water supply. Proper fill level should just touch the heating element. What cycle and options are typically used?

Is your washing machine a frontloader or toploader?

We were having issues with getting grit on our dishes in our Kitchenaid (~10 years old, think it's a KUDS). I looked a little and found this thread on the Applianceblog forum. The embedded video is pretty helpful.

I found a bunch of stuff in the sump of our washer. Misc glass pieces from broken glasses (with one slice to index finger as a result). Stuff gunking up the waste flapper valve. The label (including serial number- ouch) from our VAH from when I last ran the blower box through the dishwasher. Etc.

I've only run it once since, but it seems to have helped a lot.

Thanks, thull -- I will check out the video anon. Did you have to open things up to get at the sump? Prolly... My machine has a fine metal horizontal seive held in place by a circular vertical fine seive which appears to have something like a sump inside. I clean that out regularly, but if there's another trap further downstream, that would be good to find.

dadoes -- lol; did I say "washing machine"? I mean dishwasher. I have appliance-dyslexia. I am always saying the wrong thing. But from your comments it sounds like you understand the context.

The water temp has always been an issue and I take your and others' suggestions to heart to have the water be warm at the sink before starting the machine. Even so when I open it up the water in there is suspiciously cold.

When I care I run the temperature boost and haven't tested whether that helps, just assuming it does. The glassware looks a teensy bit better. Sometimes. But I do suspect the real underlying problem is as suggested, the detergent is bad. But I'm a happy little homemaker now and will post before/after glassware pictures. They show amazing contrast.

Still, I agree likely a change of detergent is in order and could help further. I will check the fill level. And definitely pay better attention to the water temperature if it sounds as if the heater isn't working ... what makes it sound that way? The presence of the film? Now what's present on the coils is a film of greyness. That would seem to me to be oxidized food residue, which would suggest 'working-coils', no?

BTW - and I'm sure this is relevant: we have a insta-water heater that's not really. And it's located a good, um, 35 feet throw from the dishwasher. So I think that accounts for the temperature problem, probably. I bet I can wait to start the machine until hand-washing gives me warm water at the sink, but still it has to cycle internally and I bet by the time it gets back to sending in new hot water, things have shut off and colled down and that whole distance has to get re-filled-back up with hot water. Probably I should always run the temperature boost as a matter of course, but I hate to waste energy.

*Are* there toploading dishwashers? I'm confused.... It's a KUDE70FVSS0 I'll check the fill level. I suspect that's fine but the sump may not be again, if there's one downstream from the bottom of the machine itself.

TIA! I'll report back ... but wait, I owe y'all a photo:

Yes, you do have to do some disassembly. Not sure I follow your description, so your dishwasher may be different from ours. The video has you pull the racks, take out the tube that feeds the upper rack and top sprays, then pull parts in the bottom of the machine.

Pulling the tube was slightly tricky for me (i.e. not quite as easy in video). Then there are 4 Torx screws to remove to get the sump cover and then 1 smaller Torx screw to remove the pump cover. Pulling off the pump cover also was slightly harder than shown in the video- you have to tilt it a tad to the side and pull up, but it was a little challenging with the water in the sump making it slippery.

They point to the flapper valve that's under all that as being a root cause for issues. If it gets gunked up, some of the junk that should get pumped to the drain stays in the sump and gets recirculated onto the dishes.

FWIW, we use the Finish tabs. It took me a long time to realize that it runs for 20-30 min before the hatch opens to drop the detergent. We have a box of Cascade and put some of that in the pre-wash bin when we run it too.

I tend to be an intensive dishwasher loader. This may change, but my default for a long time has been to run the hot wash and hot rinse, changing from normal to heavy depending on how jammed or dirty the dishes were. My wife doesn't do this and then would say that the dishwasher didn't work if stuff didn't get clean. We may both have been right. FWIW, we mostly don't pre-rinse (wastes water), but melted cheese on a plate is tough to get off regardless.

Thanks, thull -- you know how somehow you read something and just know "that's gotta be right; that's gotta be some of the problem"... I just know from what you're saying and from what I've been seeing that these internal parts have to be globbed up too. I'll put that task on the list. :(

It's perhaps compulsive or just anachronistic of me, but I don't just don't like the idea of those tabs. They're discrete so you can't easily affect volume of detergent used -- I know you can snap it in half but (a) that sounds like a pain to me and (b) it's only a one-choice solution, nothing variable about that. What's wrong with just pouring in some powder to taste? I feel irked by being market-manipulated by these things, I don't like that it takes extra energy to manufacture these tabs, and degrade them too, not to mention buy them. And all this I'm sure is to drive up volumetric use of detergent.

OK, over-analysis alert. Sorry. But I haven't jumped on that band wagon. That said, it's not as if the cascade powder-thing's really working so well for me .... ;)

First, I'll clean out the innards, and then proceed if necessary. But honestly, it may not be as things are Gidget-sparkly these days already. At least mid-level machine-wise. Not so much on the upper, silverware tier. If there are hoses that are a mess up there as you suggested, I guess I should go investigate...

Thank you!

aliris19,

thull didn't cite the full model number of his/her unit (there's that again, LOL) but the reference to it being 10 years old and the linked video ... your dishwasher is a different design. Yours doesn't have a grinder mechanism, thull's probably does.

Regards to "washing machine" ... I took that to mean you're wondering why, if hard water is involved, you're not seeing the same residue in your washing machine that is in your dishwasher. Is that not what you meant?

Your water heating situation could be part of the problem. Assuming the dishwasher is connected to the hot faucet feed under your sink, it's getting whatever temp is at the faucet at any given point in time. You conspicuously reference "warm" water at the faucet, not hot. What's the highest temp you get at the faucet when it's run long enough to fully purge the supply line and the water heater is producing full output? You may need to purge the line (run the faucet) again midway through the dishwasher cycle if there's a long-enough time that the flow turns cold. Adding the high-temp option should help and it's not really a waste of energy if the water feeding into the dishwasher is warm at best ... but there may be a limit on how long the machine will heat until the cycle "times-out" and continues on.

I have essentially the same hot water situation, with enough distance that 2+ dishwasher fills are needed to purge the line. Sometimes I run the faucet to clear the line so the prewash is not cold ... but my dishwasher has assured/onboard water heating. The main wash and final rinse are always heated and the cycle is extended if necessary to insure the proper temp is reached.

Yes, there were toploading dishwashers in years past. They usually were portables but Westinghouse and GE (in the 1950s and 1960s!) had undercounter units.

Dadoes could be right that I have a different type machine. I just went through this last weekend, so aliris19's situation certainly sounded similar. Our machine is a KUDS02SRSS1. I did look briefly just now at the manual for a KUDE70FVSS, and that does look like it has a filter setup that is different from ours. Have no idea if there's the potential for the more-recent one to have issues with not getting the stuff pumped out. Check the forum I linked- they're pretty good about having info on the various models.

On the detergent front, I think you just have to be pragmatic about what works. The counterpoint to the issue with the tabs being pre-measured is that it's easy to overpour (and I guess underpour) if you're using the powder/liquid by itself. At least for the clothes washer I have a cup that I fill at eye level and can be consistent with.

Also, don't treat it like you just press the button and it cleans no matter how loaded or dirty the dishes are. That's what my dear wife does- same settings every time. I think with the more energy efficient dishwashers it's less likely to be 100% successful.

Run the hot water at the sink. If your heater is set low for energy conservation, you may have to use the hot wash.

Hope I didn't confuse things. Cheers.

My dishes occasionally get hazy crud--mostly on plastic items--and then I run with lemishine mixed in. Then I get lazy and skip the LS and it stops happening. Since it's sporadic, I blame my water supply. (It does change so I'm not crazy to do so.) The DW buildup I get doesn't end up on my dishes. Or does it? I don't check that often.

I DO have a top-loading dishwasher, you know, a DW drawer. The crud is all under a plate at the bottom and is invisible until I decide to tear into the DW to clean it. So months and months of buildup. Vinegar loosens it kinda.

hah; I SWEAR posting on GW is like therapy ... all these unresolved issues just *pop* up.

Water temperature. Did I really say "warm"? Yes I did and my how perceptive you are ... "warm" is all I get. There was a time this drove me *crazy* but I have made my peace with it. I figured out at one point that the instant hot water heater has a digital thermostat and it's programmed to go no higher than 120-degrees which is basically cold, even in SoCal. I decided - but gave up before determining if this was true for sure - that it was an energy-saving ploy and/or can't-let-the-old-dears-burn-themselves public health rule that disallowed a home owner from setting their own water temperature? I figured I'd wait til the inspector was gone and figure out how/if I could defeat the default setting. I like hot water.

But I never did revisit that issue. I don't know how to get hot water in my kitchen sink! Plus, I have a Kohler Karbon which I am likely the only person on this forum perhaps who doesn't really like the thing. And the reason for that is lacking that floor switch thingy I have to actually turn the thing off with the joystick and re-finding the miniscule sweet spot that results in just-warm water is really, really hard. Between not being able to find the setting, and the long throw from the "instant" heater and its mandatory low temperature I not only don't have "instant" hot water I rarely have any of it at all.

So there are multiple problems here that I gave up on long ago. But they cascade (no pun intended cf dishwasher detergent) into problems in the DW with water temperature. Maybe.

I did just check the fill level and it is just "kissing" that heating coil, so at least that's good.

Because there is more perhaps. But first, "Hi-temp scrub" does provide hot water. I should experiment with that feature off and also compare with the "sanitizer" option which I think is hotter still. Maybe I'll take a shower in the DW. ;)

The part there's more about is perhaps not so interesting....I do NOT understand air gaps.

While writing just now I hear this aberrant water-sound and I can tell it's not good. Maybe I left the water running only I don't think so plus this is louder, heavier. This is a flood sound. Which I try to ignore because WTH, que sera sera?

It turns out that I removed that stupid air gap thingy wondering if it was dirty b/c awhile back I learned that if that thing is clogged it can actually cause the entire machine not to work.

Finding no overt clog but lots of nasty mold I left it open for subsequent cleaning and promptly forgot its existence. So evidently running the machine with that absent will cause gallons of water to spill onto the counter? I don't get this ... isn't there a functional drain pipe to clear most of that water through?

By some chance is this indicative of a clog somewhere or is this predictable stuff? I guess it's conceivable this is normal behaviour and somehow capping the pipe would have prevented all this water from flowing out of it? How? I do not understand air gaps. For reference the water that exited was not especially nasty.

Thull - nope, no confusion, just interest and thanks for the links. My machine does not have a grinder. I like the resulting quiet but not the inability to pass through stuff.

It doesn't take much detergent to lyse a lot of fat globules. I think they just want to sell more of it to you. And on an unrelated matter, I was reading lately about the woes of front loading washing machines and it seems some of their shortened longevity may be due to over-detergenting. We just use too much of that stuff. Maybe I'm over-generalizing.

Fori, do you run an empty load with just vinegar to loosen that stuff?

Dadoes - whoops; I know I wrote it but I totally forgot about that analogy to a washing machine. Indeed I did say that?! What a good question (lol) ... my WM is a front loader. But there you go asking obscure questions again: why would that matter? I know the answer is going to be interesting...

It's not just air gaps I don't understand, it's the whole of these appliances. After I succeeded in getting most of the DW's innards clean I decided to use a sponge on the last two inches at the bottom of the door. And then I just took my sponge with hand soup bubbles on it and wiped down the entire inside of the door. I didn't bother rinsing it because the entirety of the inside was about to get soaked, right?

Only the machine went through its entire cycle without rinsing down those bubbles from the door? And then it went through two more cycles without doing so, including the cycle designed for pans that spurts water from the back wall of the machine straight toward that door at high pressure. Those bubbles' residue just persists in shadow on the door. ?!? huh?! I know dishes close to the door don't clean well but this seems weird ...I wonder if - no, can't be a clogged outer arm's jet because that would make a problem equally at the back...

Lose the Cascade. Otherwise it's the definition of doing the same thing and expecting a different result.

Spent $10 on some Somat dishwasher cleaner and use the whole thing.

Then get yourself some Finish Quantum Tabs, Method Smarty Tabs (Target has those), or Ecover tabs. Some of us cut the Smarty tabs in half as half does a good job.

I also would have the water heater turned up to 125F as the KA doesn't have a heater.

Alternately, replace the dw with one that does have a heater and has a cold water hookup. Problem solved. Drama over.

There may be a programming adjustment on your tankless water heater to increase the temperature limit. Check your instruction manual. Mine was factory-set for 125°F maximum for safety but the limit can be increased to 140°F. I set it at 102°F to 104°F as "normal" (for showering) but can easily raise the setpoint as needed for various tasks.

This is off-topic for dishwashers ... tankless water heaters are most efficient when set at the exact temp that's needed for a given hot-water task, which avoids overheating the water supply. My unit is in a closet in my laundry room off the kitchen so is easily accessed for adjustment. Remote controls are available for many tankless models to facilitate adjustment from a bathroom or kitchen when the unit is not readily accessible.

Your dishwasher does have water heating but is a newer model that doesn't heat the wash water very high unless the Hi-Temp Scrub option is selected. Sani Rinse raises the final rinse to 155°F. The Heavy Duty cycle may heat some without those option, but the Normal and Light cycles may be low as 105°F for the wash period. As I stated previously, water heating may be limited in duration such that the cycle will continue on to completion if the target temp hasn't been reached in xxx minutes but that's still better than no heating.

Dishwasher air gaps function as a siphon break on the drain hose so dirty water from the sink drain doesn't get pulled into the machine. I don't have one, they're not required by all local plumbing codes. The effect caused if the air gap gets clogged is that the machine can't drain completely because the pump can't push the output water through the clog.

Overdosing detergent does cause problems ... but underdosing also impairs performance and causes residue to accumulate instead of being carried out with the wash water.

¿ Drama, rococo ?

Please note as I explained: heater is involuntarily set to 125; it can go no higher (AFAIK). The DW does have an internal heater; its physical location at the end of a long line may be a problem particularly with interaction with machine's cycles. The Somat, whatever that is, is no longer needed as the cloudiness problem is largely solved via lemishine, which I suspect is the same thing (hemihydride acetic acid; see link of above). It's also <$5. I've discussed the tablets above, their mode and my reluctance to waste materials and energy. Under the circumstances of near-resolution, it may not be necessary. However, when next I need to purchase detergent, I will definitely try your suggestion ... if I can find it in non-tablet form. I don't do Target as a rule; no drama there, just not my preference.

I've discussed the tablets above, their mode and my reluctance to waste materials and energy.

I understand what you are saying here but 1. changing to these recommended tabs has fixed similar problems for countless others here so problem solved 2. how much additional energy and resources are you using if you have to wash dishes multiple times or use extra powder detergent or your machine does not run as efficiently as it should because it is "gunked up" inside? Do as you wish but the definition of insanity is doing the same thing over and over again and expecting different results (or something thereabouts). I had a "gunk" problem, came here and saw recommendations to use a DW cleaner and switch to Finish Quantum tabs. I hated to switch from the brand I used also as it has less chemicals and such but what good is using it if I have to double wash or hand wash before/after using the machine? That's a terrible waste of product and water and energy! I followed the advice given and now my dishes are sparkling clean along with the machine. I wish you good luck with yours and hope you have success with whatever method you choose to stick with.

@mhwhetsell -- well said and accurate.

@aliris - Water heater is optimal at 125F. If the DW isn't producing hot washes on sani or other hot wash cycles then either the DW heater isn't working or there is some other issue that a plumber should be able to solve.

Glad the gunk is receding. However, Somat is an outstanding German product that is worth the $9 as it will leave the machine sparkling clean. Somat dishwasher tabs and rinse aid are top of the line. I received a few as a gift from someone whose family sends them from Germany. They are the bomb. If you can do as well for less that's great but I tried Lemishine and still suggest the Somat.

As the previous poster stated, this isn't a new or unusual topic. It's come up over and over again has been linked in the past to using Cascade for many posters. The various tabs suggested don't seem to cause any issues for anyone. Their effectiveness varies with everyone's water but the tabs I listed seem to work best overall.

Whether or not you want to accept it, the default solution is switching to one of the tabs mentioned. I sourced Target for the Method tabs only as a convenience to you. They aren't sold everywhere though Drugstore.com also sells them.

When I ditched the Cascade all the problems went away. Also, I also didn't care for breathing in the dw powder dust. Suit yourself.

Somat has phosphate in it. So you're buying from overseas, hauling heavy powders across the ocean to circumvent environmental laws here in the US and exascerbating eutrophication. YMMV not to mention your politics, and true enough, one could argue that the acetic acid in lemishine is not exactly mother's milk for the pipes (Hello, Flint) (I believe for some reason it's said to be not-intolerable for the environment, it must neutralize fast or something?). But I will repeat: that problem is now in hand so while I will keep the recommendation for a change of underlying detergent in mind, there's no immediacy to toss good-enough stuff for now.

rococo - Again (x3): hot water is present inside machine; coils are working. Hot water may not be present sufficiently frequently due to on-demand water heater being far away - I've yet to test this but when asked to boost the water temp, the machine functions to do so.

The real problem for me is the *involuntary* -- read: I Can Not Change This temperature of the water. And I mis-wrote above on the repetition that the involuntary maximum water temperature is 125; it is not, it is 120. I just checked again.

Also, though I did not mention this earlier, I, too, have started and contributed to these threads in the past when the issue was cloudy glassware. I have tried switching detergent in fact and it was not helping appreciably, or reliably. The comment here was about the machine itself. That is what alarmed me this time. I admit, it is possible the same problem underlies both issues and this appears evident as succeeding in getting the machine clean has resulted in ... hey, presto: clean glassware. But that was not my initial problem. And yet, the glassware has served as something of a canary-in-the-coalmine. Silverware is not so clean so some of the problem may be mechanical yet and being pointed to the dishes as indicators is helpful in parsing the problem. Thank you.

Did you catch what I suggested above about checking whether your water heater has an adjustment or secondary options menu with a setting to increase the maximum allowed temperature? For example, here's a video explaining how to override the limit on a particular brand/model.

Noritz Tankless Temperature Override

Oh geez, I missed that earlier. THANK YOU dadoes. you will SO have made my day if this works.... I've been an inverse frog in the pot just accepting, with time, all this lukewarmity .... oh... I hope.... and how did you know: it's a Noritz I have too! (and no, I do not as of this moment have the model no, lol!)

LOL, I have no way to know what brand/model is your tankless. I did a search and one of the hits was to that video so I linked it just to illustrate to you the possibility of an override on the limit. :-)

OMG that's so ridiculously easy.... all these years I cannot believe it! I can't wait to have a HOT shower! I better warn the rest of the family...

Dadoes I am incredibly grateful. Thank you.

Hot showers are pretty nice.

I should mention that vinegar might not be good for seals and stuff. I don't know, and do it anyway (NOT very often, as the gunk buildup in a dishdrawer is hidden under a big plate thing). At that point in cleaning I have the sprinkler thingy and the plate off, see the gunk, add the vinegar, and let it sit for a while. Then I start to chip it off, realize I don't want that stuff going down the drain, pull out the chunks, and set it on a rinse cycle. Come back later and remember that it won't run without the spray bar, reassemble, run it, redisassemble, chip out junk...it's like chalk, but not chalk, right?

Ack. I can't believe I used to do my own car maintenance. Maybe I used to be more competent...

yowch. You might want to try the lemishine, which is a variant of citric acid. So, stronger than vinegar, same idea though (easier on the sinuses. Careful inside of that machine with the vinegar bouncing around). YMMV in terms of how you feel about your personal environmental destruction footprint. Personally, I'm OK with this but that may just be because I haven't been told by the FDA or EPA it's bad. Ignorance is bliss. But mostly, you/we/individuals are puny in the scale of things.

Fori, sounds like you're having build-up of mineral deposits from hard water. My DishDrawer is 12 years old, been on well-water for 10-years and I don't have residue anywhere near to the degree you describe ... because I use phosphated detergent that properly deals with it. ;-)

But dadoes, phosphated detergent has phosphates.

I don't use phosphated detergent. Usually I use Method. However, solving an ongoing issue in a dishwasher with something that will get rid of it seems like a smart move.

lol dadoes.

If I don't take it apart and look at it, it doesn't bother me. It's not affecting performance. The little bits of calcium that formed inside the spray bar and bounced around blocking holes, on the other hand...they really did have to be dealt with. So yeah, I guess it's hard water. :P

I'm not sure having the tankless set to 120 vs 130/140 will make much of a difference with newer efficient dishwashers. My tankless is set at 140, and I just replaced a 10 yr old Maytag with a Kitchenaid KDTM354DSS. With the hot water at the kitchen sink primed til its hot, I measured with an IR gun 130 deg at the tap. With the initial fill at the DW right next to the sink, the water is a tepid 87 deg with the IR gun - it just doesn't use much water, and the stainless interior futher cools it pulls down the temp.

The KUDE70 manual says it uses maybe a half gallon more than the KDTM354 per wash, but close enough that has signfiicant cooldown. And by the time it does the later fills and rinses, the water in the pipes will be back down to room temp. So the wash temp really seem to rely primarily on the internal heater rather than incoming temps.

The prevous Maytag wasn't that old, but definitely filled with a lot more water, and while also stainless interior, definitely the larger volume of water started out much hotter after the initial fill

43°F temp drop seems a lot. However, the resultant temp in the dishwasher would be accordingly lower if the supply temp was lower. 110° supply - ?°F in the dishwasher?

43 does seem like a big drop. I can only measure the supply at the faucet, which is probalby the same temp at the undersink valve where the dishwasher supply hose splits off. But that 6' supply hose is both filled with cold water and will also cool down the incoming water until it heats up, so I suspect both a slow fill rate and a small total volume is causing the large drop.

But the heating element is doing its job and heating up the water to about 105 after a few minutes, and it cleans much better than the old Maytag (even when using the Hi-Temp 160 deg wash on that one). So no complaints about the end resul.

Same issue with big temp drops measured in my Samsung front-load washer, again a small volume of water used, big temp drop in short supply line, and stainless tub. Which was the main reason I keep the tankless at 140 deg, to get to about 110 deg IIRC for a large load.

wwu I haven't these accurate measurements but they do comport with my *sense* of things too. Boosting the temp ten degrees did make a big difference empirically from "warm" to "low-hot" inside the DW. I do still, again without rigor, have the sense that using the internal water temp booster adds additional improvement, and that boosting the line temp would too. All the while noticing, again, that things are definitely hotter inside than formerly- that is, the internal coils are working.

Yes, I recall upon purchasing the DW that it uses a remarkably little amount of water to clean, really qualitatively different/less than previous generations ... and wondering how that impacts things like internal water temperature piped in. Making sure the water at the tap is hot before running makes a big difference, but if you forget to turn on the machine at dishes-time meaning you have to wait for that water to get hot just by running water uselessly down the drain ... that feels pretty icky!

Clothes I wash in tap-cold anyway (another reason the hardness issue might not have been showing up there for me).

Seems an open question to me energy-conservation-wise as to whether it's better to boost the water temp specifically in the DW per run or at the insta-hot water machine and lose that extra boost while it travels inline. Probably the DW is less efficient at heating than the water box, but that water has to travel and thereby cool down .... ugh. At some point all this cogitating.... MAybe the "rule" should be if having to run from cold, then boost at the machine, but if you remember to turn on the machine at dishes time, it might not be so necessary ... though this doesn't really gybe with wwu's measurements....

fori - I suspect my upper arm spritzer has some clogging too. In the list of things to do (downstream) to get in there and check, somehow.