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stagr.lee

Bosch Dishwasher stains... Rust/Burns?

7 posts in this topic

I come to the dojo seaking knowledge and harmony.

 

This is a Bosch dishwasher, well over 5 years old.  It started staining the dish tray about 4 months ago.  Just noticed the bottom of the plates started getting the same stain.  Is this rust or overheating thermal stress?  I run about 10-12 loads a week in this thing.  I live in Austin, TX which is primarly limestone (not much if any iron).  I use the Quantum Finish Powerball detergent pucks.  The house has a beefy whole house water filter which catches most of the lime and chlorene coming in from the water supply.

 

Model number is SHU9922UC

 

Thanks for your wisdom!

Stagr.Lee

 

Rust or burn marks?

Edited by stagr.lee

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Need appliance parts? Call 877-803-7957 now!

I see a "rainbow" effect on your stainless steel tub, which could be attributed to your water hardness.  Try a ph water test kit, they're available almost everywhere.

 

As far the dishes, could still be a washability problem.  Check the lower spray arm for debris inside that may keep it from properly rotating and spray.  Also inspect for any cracks, particular at the seam.  Check your drain hose for proper installation.  There should be a "gooseneck" formed by the hose where it attaches to your disposal or sink drain.  And try a different detergent, one that you can adjust the amount used.  Be sure to use a separate rinse aid as well.  Detergent and rinse aid usage can be critical for these energy efficient dishwashers.

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water issue

 

could be your pipes in the house or

 

is it connected to hot water ?, could be coming out of your HW service

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Great advice guys.  Checked the spray arms, no cracks or clogging.  Found some calcium build up but not enough to prohibit movement.  The caked calcium was the same color as the stains on the trays, dish bottoms and the sprayer exterior so I think everything is lime with some kind of detergent staining.  The stain comes off the dishes with some softscrub. A finger nail will get the stain off the plastic bits inside.  Feels like lime so I ran a load with a cup of vinegar and it knocked off quite a bit of the staining in the machine.

 

Checked the gooseneck, looks good there.

 

Checked the anode in my 8 year old water heater.  It was due for replacement so I popped a new one in.  About 1/2 of the magnesium was gone.  I think what happened was I didn't flush the hot water tank long enough last time and a cloud of limestone ended up in the dishwasher.

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Lemi Shine for the win.  It knocked the stains right off.  Ends up my Dishwasher was new in 2000 (model SHU9922UC/U12) and back in shape.  BTW - I've been lurking on this site of and on for years and finally get teh Frank Zappa reference.

 

Lemim Shine Fix

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Lemi-Shine is great stuff. I use the rinse aid version and I have a case of the boxed ones that your showing. I give them to customers who are having similar problems.

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CLR work pretty good as well.

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