Re: Galvanic corrosion and dissimilar metals

On Aug 2, 9:14 pm, "Coffee for Connoisseurs"
<alanf...@xxxxxxxxxxxxxxx> wrote:
AFAIK I was the first person to post about the galvanic corrosion of
specifically Gaggia boilers about 10 years ago. At the time I'd been asked
to fix a Baby Gaggia by a friend, who was as shocked as I was when we opened
the boiler.

We then trucked off to the local Gaggia agent, who had been importing Gaggia
machines since the 1950's, and talked to a Gaggia factory trained
technician. He identified the problem as galvanic corrosion, explained the
cause (brass & chrome bottom mated to alu top), commented that it was worse
in Melbourne than in other cities due to our soft, acidic water supply and
that he could usually identify which city a machine came from by the state
of the boiler. He also commented that Gaggia Italy was well aware of the
problem but ignored it, as it usually took a couple of years to manifest,
long after the warranty had expired. Most of the rest of the world had
harder, more alkaline water which also extended the boiler's life.

I've seen the same thing happen with alu thermoblocs at the "point of
contact" of brass fittings. Not surprising that these days even chinese made
machines offer stainless steel lined thermoblocs, and Gaggia has moved away
from the alu boiler tops.

--
Alan

alanf...@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

I just did a spot check of the drinking water of eight municipal water
systems across the US, and all were *neutral* or *basic*, with none
being *acidic*. So I'd say you're observations are unique to small
communities with acidic water supplies. If that's true then damage to
your Gaggia is of minor concern - just think what that water is doing
to your water pipes & plumbing fixtures?

I would be curious to hear from other people here in the US &
elsewhere regarding their water hardness?

Gaggia is not stopping production of the aluminum boilers, at least
not in their biggest market, North America. Todd Salzman of Importika/
Whole Latte Love, Gaggia's NA importer, says they considered it but
have decided to keep them in their product line up.

I've looked in hundreds of Gaggia boilers, and I've had folks send me
photos of hundreds more, and I've only seen one that was damaged to
the degree mentioned. The ONLY comment I'll make about that one
machine is that wasn't the only problem the owner had. I concluded
that anything can be damaged if ignored until it breaks.

Tex
.

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