Carbonic acid in L1 copper boilers

Matthias Jakubek

I just read the following in the BWT filter manual:

Coffee machine materials: Due to the process, decarbonised (descaled) water contains free carbon dioxide. No installations made of copper or with nickel or zinc coatings should be used after the filter.

Is this something to worry about?

Best,
Matt

Reiss Gunson

hi Matthias

not a single instance of the BWT water filters being an issue has been reported to us

that said i think they are a fairly expensive way of protecting your machine and i think most owners use a bottled water that is suitable for espresso machines, such as Volvic

kind regards

reiss.

Matthias Jakubek

Hi Reiss,
imho buying Volvic to fill my espresso machine contradicts the idea of simplicity that you have worked into the Londinium-DNA ;-)
However, the reason I'm asking wasn't related as much to damaging the machine/boiler (I assume it would take quite some to show effects of wear) as it was to damaging my health with copper or brazing solder.
Have you or has anyone ever measured the water quality that comes from the machine for copper or lead contents?

Thomas Brettinger

Matthias,

there has been some discussion on lead in Espresso machines (not specifically the L1, but any) in the german kaffee-netz for quite some time (years...).
It seems there are some machines that have a measurable amount of lead in the water, especially after descaling.

I'm no expert concerning water chemistry, so I may have mistaken some things, but here's what I think about the BWT statement:
carbonic acid and calcium (sorry, don't know the exact word - meaning the substance that is mainly causing the "hardness") are in balance in the water normally. Depending on how you remove the calcium ions, the pH lowers as the relative amount of the acid gets higher (or the calcium which, when present, was neutralising part of the acid is now gone). - I hope I got across what I wanted to say, and I hope this was not total bullshit

So in short - it may happen that, if you filter out the calcium, the water gets more acidly, and can (in theory, at least) over time dissolve copper tubes or solder.

I personally doubt that the pH will get low enough that this is an issue while you can still produce a drinkable espresso with that water. But that's for someone else to answer...

Regards.
Thomas

Reiss Gunson

hi Matthias

our boilers are made from pure copper with brass fittings

copper is copper, it is not alloyed with anything else, including lead

copper is not regarded as toxic, unless you are looking in the corners of the web where stainless steel also has concerns raised about it's toxicity

brass is of course an alloy, however we use lead free brass

kind regards

reiss.

Matthias Jakubek

Thanks to both of you.
The mind sometimes tends to overreact when your wife is pregnant ;-) and since I have a friend who accidentally poisoned her child during pregnancy with lead from an amalgam filling removal it suddenly sparked up in my head.
I know copper isn't toxic, however, there is some debate about its effects on the brain in relation with alzheimer's disease (this isn't something I found in the corners of the web, my wife holds a PhD on the subject).

Best,
Matthias