Rusty cutlery from the dishwasher

Living_proof

I have been led to believe that the different weights of stainless steel contribute to a chemical reaction which creates these rust-like stains.

This may explain why some people have no reaction for years but after they supplement their collection of cutlery over the years and the grades change, that whatever this reaction is, occurs. We briefly had some Lidl steak knives which were sold as stainless. However, in the dishwasher the little circular steel bits on the sides of the handles became detached and metal beneath seemed to create stains on the hitherto immaculately stainless steel Oneida, etc. cutlery. We have long ago chucked the Lidl stuff as far as we could see it, but there is still odd staining on the rest of the cutlery.

The moral of the story seems to be wash the same family of goods together and if in doubt, chuck it out!

bluebag

I live in an area with very soft water, so I don't use salt at all and just use the value boring tablets, never had any rust on anything. I do use a little rinse aid tho.

harrys_nan

I agree with bluebag, You do not need to use salt if you live in a soft water area nor do you really need rinse aid if you use the all in one tablets. Was talking to the repair man yesterday when he came to repair my dishwasher

murphydog999

I thought after 2 pages this might have come up - a little trick from a friend of mine in the restaurant trade - rub with the flesh of a lemon, it's worked for me before. In fact, periodically, she soaks all her cutlery in lemon juice and water, they are always shiny.

andyrules

I have just changed my 13 year old Zanussi for a Bosch and for the first time ever had rusty cutlery.

I am wondering if Badger has a point as since I've had the new machine I've used the expensive tablets - largely as there have been some good offers! Normally, I use the value ones.

However, this new machine guzzles salt whereas the old one had no indicator so only occasionally got topped up. Salt def causes corrosion. seems to be no difference between quality of the cutlery.

witchychris

Hi. I have been having this problem and think I may have solved my problem now. I have the Economy 7 electricity rate through the night so have been setting my dishwasher to come on just after the cheap rate starts and then emptying it in the morning. Where I lived before I had no cheap rate electricity so would use the dishwasher during the day and empty it as soon as it was finished. No rust all those years.
I recently started setting it to come on at the end of the cheap rate and opening the door a little whilst it was at the end of the drying cycle. No more rust! No more streaky smeared glasses! Problem all gone!
So I think it must be leaving the dishwasher closed and the pots/cutlery in for a long time after the cycle has finished that was causing the problem. Hope this helps

eghughes

I work in a kitchens utensil store and we've all been trained that stainless steel actually means that it will rust less then normal steel but will not be completely free of rust.:( You can buy stainless steel cleaner that will get rid of the rust.

I've also heard that you can also use potato peelings with baking soda to help scrub off the rust, which you then rinse and dry, although i haven't tried this method it does seem more OS style:)

Hope this helps:p

DorzetLad

Here's the answer!

Talking to Bosch, it's caused by metal-to-metal contact on the cutlery box. Which is why new dishwashers have fold over lids on their cutlery boxes where you insert an item of cutlery which doesn't touch its neighbour.

spoeksy61442

I think a dishwasher working properly will not release concentrated salt solution into the washing water. The machine usually has a water softener (ion exchanger) which exchanges the calcium/magnesium/iron ions in the hard water from the water supply for the sodium ions in the water softener. Over time the softener gadget become depleted and the dishwasher salt is used by the machine to top up the sodium in the exchanger gadet. the sodium should not be rusting your stuff as it doesn't go into the machine in concentrated form. The water that goes into the dishwasher is tap water that has been run through the exchanger. Most of the sodium stays in the exchanger if it is working properly..

The machine runs the recharge exchanger cycle every so many operations of the dishwasher. When the recharge feature runs the sodium rich solution is pushed into the exchanger and recharges the exchanger and the excess goes into the drain (not the washing tub). The concentrated salt solution does not go into the tub.

If the salt is being consumed too quickly then the machine is running the recharge cycle too often or the sodium solution tank is leaking. It could be the solenoid is stuck on and the recharge is running on every dishwasher cycle. It could be a leaking cap on the softener reservoir so check that it is sealed properly. If your dishes taste salty then your exchanger is broken!

The dishwasher itself is stainless steel and does not usually rust. However it does happen if the metal is damaged.

I suspect this is some other chemical reaction i.e. cheap stainless steel or the dishwasher detergent is causing the damage. I'd think that the silverware vibrating against other silverware might be the issue - especially as newer dishwashers have swapped high temperature programs for high pressure water causing more vibrations.

you can check the water hardness of your supply at the web site of your water company. If they say your water is < 3.7 mmol then you can just use the tablets that contain softener and you don't need ot waste money on salt. If your water is < 1.2 then you don't need a softener at all.

Most tablets seem to come with water softener these days. You won't need both if you are in a medium hard water area or lower. However as the tub of the dishwasher does not rust you can't blame the problem entirely on the softener. If your water is too soft it will add to the glass corrosion problem. Rinse aid with glass protection tries to overcome water that is too soft for rinsing glass. Glass damage will still occur due to the detergent etching.

Combination tablets that have water softener are probably not "Salt" - at least not the sort that you'd put in the dishwasher or on your chips - it will be some sort of Phosphate or Citrate compound that reacts) with the magnesium in your water. Some people use lemon juice as a substitute (dishwasher tablets probably also contain citric acid). I don't know for a fact but I'd suggest that citrate is a better environmental choice. You might find on the eco tablets that it lists their chemical components. Most phosphates in our water come from fertiliser used on the land and the dishwasher tablet industry is not under a lot of pressure to reduce phosphates.

Softened water uses the detergent more efficiently (if using powder you might need twice as much powder in unsoftened water - same as you will read about on your clothes washing machine powder). Leaving salt out is a poor economy choice as it is so cheap. Add salt and you might find that you can get away with using half a tablet. Leave salt out if you have soft water from the tap. using less detergent is a good choice for economy and the environment (as long as you don't end up having to wash everything twice!)

Table salt is not suitable for the dishwasher as it contains magnesium or other stuff to make it flow freely and avoid clumping when wet - the ion exchanger is designed to remove magnesium from tap water so putting magnesium into the exchanger is a bad idea. dishwasher salt is pure sodium chloride. I'd use Aldi or Lidl as salt is salt.

Running the fast wash or economy program will leave the utensils in the rinse water for longer as that cycle does not try to dry the utensils. If you are using those programs you'd probably benefit from getting the utensils out quickly and dry them by hand.