Descaling TEA coated boiler?

Equipment doesn't work? Troubleshooting? If you're handy, members can help.

#1: Post by boren »

I'd like to descale my Quick Mill Alexia Evo, a single-boiler E61 machine with a TEA coated boiler. A previous thread from 2017 with the same title as this one suggested dismantling the machine, which I prefer to avoid. It also made no specific suggestions for a descaling product which is known to be compatible with such boilers. 5 years later, is there any established product/process I should use? Quick Mill doesn't mention anything about descaling in the instructions manual and is not responsive to my emails.

Note that I'm using soft water for the past year and a half, but unfortunately did not in the first couple of years. The machine overall works well, except that temperature stability is not what I would expect from a PID-controlled machine.

boren (original poster)

#2: Post by boren (original poster) »

I found some info in the instruction manual for the Quick Mill Monza Evo super-automatic machine - Quick Mill "Recommend using Dezcal or citric acid".

On some other websites it's claimed that "ALL Quick Mill espresso machines are manufactured with T.E.A coated boilers", if so, Urnex Dezcal might be the answer. It contains: Citric Acid; Sodium Salt; Sulfamic Acid; Aluminum Sulfate; Hydrated Silica

boren (original poster)

#3: Post by boren (original poster) »

I sent an email to Durgol about this and received the following reply (I omitted full names from the quote below, for privacy reasons):
Dear Mr. B.

Thank you for your interest in our products.

Our product "durgol swiss espresso" was special developed for automatic Espresso machines.
It contains corrosion inhibitors that also prevent acid attack on the TEA® coating.
According to a toxicological risk assessment, the product is also suitable for use on surfaces that come into contact with food (Food Safe).

TEA® is a very stable, electro-deposited intermetallic replacement for the classic nickel-chromium layer on electronic items for industrial fittings and devices for the food industry (e.g. for coffee machines).
The TEA® coating has almost no porosity and is therefore particularly resistant to corrosion. Furthermore, it has a high temperature stability and is chemically relatively inert.

All laboratory tests with TEA® coatings and our product showed optimal descaling performance values without causing chemically induced impairments to the materials.

I hope I could help you .....

With best regards from Switzerland
Dr. H.H.
Chemist R&D, EHQS
Nothing to add. This is an excellent, detailed and authoritative answer. I'm getting their product and not looking back :-)