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  for Metal Finishing since 1989
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Help determining what mystery metal my water distiller is made of

I purchased a water distiller which has a heating element located below a stainless steel tank. Upon first use, the heating unit left a mark on the bottom of the "stainless steel" tank in the same shape of the heating element (I assume the same-shape, I didn't want to take it apart.) I questioned the dealer, who also claims to be the manufacturer and he said it is 316 stainless and that the mark was normal. He said to use the stainless steel cleaner/detergent and that would take care of it. It did, in fact , and it removed most of the mark but there are still some little dots. The strange thing is, and where I need expert advice, was when I put a magnet on the surface where the element appeared to affect the metal, the magnet did not stick but when I place the magnet on the side of the unit it sticks (same surface just a few inches from affected spot.) My concern is that I would drink water coming from this unit and worry that it is leaching. Please help as I am in a dispute with this individual over this and have read contradictory info on the so-called magnet test. Is this stainless steel or some other metal with coating?

Daniel Lawrence
consumer - CT
July 21, 2008

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First of three simultaneous responses --

Commercial units are made of SS, so you are OK. The Mfg. probably put the element in direct contact with the container which is causing the discoloration. The unit is more efficient this way vs being fairly close to the tank. 48 years ago, my wife thought that there were only 2 speeds on an electric stove for "boiling" water. The SS pan had the marks on the inside from the cal rod element every time. We lived, so I do not see any problem with yours.

James Watts
- Navarre, Florida
July 23, 2008

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Second of three simultaneous responses --

Stainless steel is an alloy metal ,usually,of 18% chrome and which is a nonmagnatic . I believe magnatic properties changed near to the heating element .

Khair Shishani
aircraft maintenance - Al Ain, UAE
July 24, 2008

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Third of three simultaneous responses --

There are many types of "stainless Steel". 316 is not magnetic but other types can be.
Any metal contamination in the boiler side of a distillation apparatus is not relevant. The purpose of distillation is to remove it. What matters is any contamination of the condenser and collector.
The real mystery is why you should want to drink distilled water

Geoff Smith
Hampshire, England
July 24, 2008