Removing scale from water kettle

[kongjie]

I use a plastic Bodum water kettle in my pathetic little cubicle at work. Some time ago I noticed that the stainless steel heating element was collecting scale but I put off dealing with it.

Finally yesterday I got around to buying some citric acid and today I put about 50g in hot water and let it soak. My first surprise was that I thought there was supposed to be some effervescence. It didn't really fizz or anything.

More importantly, I am now not sure if this is a scale problem. After using the citric acid, what's left is a few areas of copper-colored discoloration. It almost looks like the stainless steel has flaked off and revealed the underlying metal. But I'm sure that I would have noticed metal flakes ending up in my tea.

The citric acid removed the greenish-blue deposits, but the underlying copper stuff doesn't come off even with scrubbing. Any thoughts?

 

[Dennis]

Looks like the coil is plated to me and the plating was eaten through. The citric acid removed the scale showing what was underneath. Bear in my mind my guess is worth what you paid for it....

 

[Alacrity59]

To me it looks like chrome plating flaking off. I don't see anything that looks like scale.

 

[sehrgut]

It's not a big deal if you're not boiling distilled or deionized water (which you shouldn't be using for tea or coffee anyay). Distilled/DI water might pick up a detectable amount of copper, but tapwater -- purified or no -- should be fine.

 

[Hobbesoxon]

Don't drink from that!

 

[sehrgut]

Por que? Bothersome amounts of copper aren't going to dissolve in tap water. Heck, I bake in untinned copper molds sometimes . . . and cook with copper implements.

 

[kongjie]

I guess that's the ultimate question--safe or not safe?

Looking at it again, it is definitely loss of the stainless steel plating. You can see other dark spots where the plating is evidently being eaten away, and the metal underneath is beginning to appear.

I guess it's time for a new pot.

 

[_JP_]

That's not scale, it's rust!

 

[sehrgut]

You're missing the point. The scale _was_ there. Now it's descaled, and with the scale came the plating, exposing the copper shell of the heating element. That's not rust, it's copper.

 

[_JP_]

Either way, I would be loathe to drink from that. Once the plating starts to go, it keeps on going.