Oops...lazy boy mistake

[Farmbrew]

Off to france 3 weeks ago and I had just cleaned up my boiler. I left the hop screen (stainless braid hose) in the bottom and chucked in what I thought was water.

3 weeks later I am just going to clean it up when I find the chrome (???) Off the element has been stripped leaving a lovely copper oxide colour.

I'm assuming there was a galvanic cell at work while I was away. Ive cleaned everything up but I think I'm going to have to use another element as I'm not sure it is copper that's exposed.

Any opinions/experiences?

F

 

[Vossy1]

I'm assuming there was a galvanic cell at work while I was away.

Sounds about right, I too had the same thing with my herms heat exchanger, I now drain it down between brews. You can buy sacrificial anodes from chandlery shops to get round it, if you want.

 

[Farmbrew]

Thanks V...I'll try to be less slap-dash next time.

F

 

[Algernon]

Are sacrificial anodes food-safe? I wonder which metals are used in them. Also, can you get a similar galvanic cell effect if you leave any two different metals in contact with water for a length of time? I would have thought so, but I could be wrong? Is it best practice to drain down and not soak for excessive amounts of time (i.e. overnight, but not longer)?

 

[Vossy1]

I wonder which metals are used in them

Pulled from Wiki

There are three main metals used as galvanic anodes, magnesium, aluminium and zinc. They are all available as blocks, rods, plates or extruded ribbon. Each material has advantages and disadvantages.

In my reply above I was talking about using them in a part of a brewery where beer does not come into contact with them, sorry for any confusion. I wouldn't be using them anywhere where the product is likely to be ingested.

Is it best practice to drain down and not soak for excessive amounts of time (i.e. overnight, but not longer)?

Yes, but again it depends on the metals involved, if all stainless then there's no real reason but with any mix of metals it would be best, in my VERY limited experience :grin: