What is wrong with my dishwasher?

[Mike Johnson]

I have a Bosch SHV68E13 dishwasher and until recently it has been a great dishwasher. Now, though, it does a terrible job cleaning dishes, and leaves residue on them. Glasses in particular come out looking worse than they went in. Here’s a measuring cup that was sparkling clean when I put it in as a test (look especially at the handle which looks like it’s frosted glass):



It’s not that I’m putting in clean dishes and thus using too much detergent. I have always put in dirty plates, and they’ve always come out clean. Now they come out less dirty, but still with bits of spaghetti sauce that have to be scrubbed off by hand.

I have a water softener and I’ve checked that it’s working. My softened tap water registers at less than 10ppm, which is the lowest bound on my test kit.

I’ve checked and cleaned the filter in the bottom of the dishwasher tub, checked and cleaned the spray arms.

I’ve tried different detergents and different rinse aids, and in different amounts, and even none at all.

The wide swaths of filmy sandpapery residue, like you see on the handle of the measuring cup, respond by foaming vigorously when I clean it off with a strong acid.

If I use no rinse aid, the dishes come out dirty and spotted and filmy. If I use the lowest setting of rinse aid (1 on a scale from 0-7), the dishes come out dirty and spotted and filmy with rinse aid streaks.

The water comes into the unit just fine and is heated until it’s very hot and steamy.

I’ve run the beast with the door open to check and the two spray arms and top whirligig work as they should.

Turning on the heated drying doesn’t help.

There’s no obstruction or problem with the drain line. It drains beautifully.

I’m not eager to throw $500 at a repairman to fix a five year old dishwasher that cost me nearly $1000. And honestly, I’ve never been satisfied with the services of any appliance repairman that’s come to my house. But I’m not crazy about just throwing away a 5 year old dishwasher and buying a new one. Is there some way I can diagnose this myself? I’ll take the dang thing apart and replace the guts if I’m sure I’m replacing the right part. But how can I figure out what’s not working?

[Kraniac]

Use less soap and less hot water...You sure that water softener is working ok?

This etching can also occur in hard water that has been softened by a water softener

Soap will do this and is aggravated by hot water
Have you recently switched soaps?

It looks etched..is the film removable anywhere?

This process happens over time and when it reveals itself as "etching" it's the final stage..you r stuff could have been going through the beginnings of the process of etching and you didn't notice until now.

[Kraniac]

Q: What causes glassware etching in dishwashers?

A: First, you should be sure that there is not a deposit on the glass. To confirm a water soluble film, run water over the spotted area and blot dry with a paper towel. Examine the spot to see if the residue has been removed. Removal indicates water soluble deposits. To confirm a hardness deposit, determine if the film can be scratched off with a knife or similar object.

Causes of etching
If it is not a deposit, it is probably a type of etching. There are two different causes for what appears to be etching on glassware:

1. Silica Film

In the early stages, glassware develops an amber to multicolored film, similar to an oil-on-water film. Lines of white or different colors commonly break the film’s uniformity. These lines follow deformities or stress lines in the glass.

As the process continues, the glassware develops patches of clouded glass (etch). Neither the films or the etch will respond to acid or bleach.Scratching with a pin or knife will remove the colored phase but not the white or etched areas.

Generally, silica film occurs in softened hard water and is worsened by:

High water temperatures;
Poor rinsing caused by overloading the dishwasher;
Use of high phosphate detergents, which are more aggressive to glassware in softened water; and
Some glassware is more prone to this problem.
Damage done to the glassware cannot be reversed, but the process can be slowed by:

Lowering the water temperature to less than 140 degrees Fahrenheit;
Not overloading the dishwasher
Using the minimum amount of detergent that will provide clean dishes; and
Using detergents that have low phosphorous (ask for one that is made for soft water).
2. Deterioration by hot water and detergents

A second but similar problem is etching whereby some of the material is removed from the glass. First, try to confirm the etching. The glassware will appear cloudy; this can be a uniform haze or blotchy, as in the last stages of a silica film problem. Again, scratching or treatment with water, acid or bleach will not remove the apparent film.The deterioration of glass by the action of hot water and detergents…

…is more prevalent with softer water;
…is very common in softened water as part of the silica film process;
…is accelerated by high water temperature; and
…is worsened because the detergents are more aggressive in removing metal ions from the glass, causing microscopic roughing of the surface.
Remember, these detergents must be aggressive to work with very hard water. To minimize the deterioration rate:

Reduce the water temperature to less than 140 degrees Fahrenheit;
Use much less detergent (sometimes as little as 1/3 of each maximum fill mark ); and
Look for a soft water detergent.

[neophyte]

Did the source of the water change? Do any of your neighbors suddenly have these problems too?

[p8712]

Buy this and use it. Just once.

Then use this with every load.

It will solve all of your problems. I've seen them in action many times.

The lower phospates now required by law in detergents cause it. Environmental protection.

I don't want to oversell it, but you'll name you kids after me.

[bwicklander]

Have you clean out the filter? Sounds like your dishwasher needs a good cleaning.

[Mike Johnson]

Our water source has been changing as a result of the drought, so where it was once 250ppm it’s now 500ppm as we draw on more groundwater. I’ve adjusted the water softener accordingly so it cycles more frequently, but this happens even with soft water. If there’s some other issue with the water, what would it be?

[Mike Johnson]

I ordered them, thank you!

[p8712]

Mike Johnson wrote:
I ordered them, thank you!

I'm in Florida, with incredibly hard water. They really, really work - read the Amazon reviews. Run the diswasher magic through your hottest cycle in the empty dishwasher, then wash you dishes in with your regular soap and some lemishine. You'll see changes. Worst case scenario you need two bottles of Dishwasher magic, but that's rare. I have 'fixed' dozens of people's dishwashers this way, including my own. It's a pretty cheap solution. Let us know how it goes.

[Mike Johnson]

Yes, I’ve cleaned the filter, as well as the inside of the thing. Many times, in fact because it builds up a film just like the plates and glasses. I scrub the racks with acid and then triple rinse them outside. It’s difficult to clean the inside of the dishwasher because I’m not going to use strong acid there, and it’s awkward as a cat in a tube sock, scrubbing inside the thing.