Hi,

I just successfully descaled my 87 Cremina, following Olympia's descaling instruction on their website, using a tea spoon of citric acid, leave it on for an hour and drained and rinsed... All came out good.

Of course, I then tried to descale my 84, which, so far as I can tell has had minimal use, I got it from someone who basically never used it. The water came out light blue, so there was some scale, but what was alarming was there was ton of metallic coating that came off the inside wall, I am trying to get all of it out for fear of it getting dislodged somewhere in the grouphead.

What is the boiler coated with and why? does anyone know, it's too late for me to worry about it now, but how do I get all of the coating of? more citric? Durgol, which I avoided in the first place after reading on this forum of how aggressive it is as a descaler.

thanks for any insight.

Steve,

The blue is copper salts. The heater element in the boiler is copper.

Marvin

The silver metallic metal flake is the plated coating on the inside of the boiler peeling off. The entire boiler is metal plated (I do not know what plating they used). Originally the inside of the boiler looked just like the outside....a silver metallic plating over the brass boiler. The scale inside the boiler actually seems to hold the loose plating in place and descaling removes the matrix which is stabilizing the plating flakes. The plating flakes are most noticed on the very top inside of the boiler since the plating is mostly gone from the lower parts on an older machine. To solve this problem in one bold stroke, one must remove the bottom of the boiler scour the inside with steel wool or equivalent....the other approach is to fill the boiler 1/2 full and shake the water around cocktail shaker style then dump, repeatedly, until you feel like you got all the flakes....heat cycle a few times and dump again and if you see more flakes you will eventually realize that you have to do the scour, even though it pains one to have to do this.
These flakes will lodge in the dispersion screen and in the steam wand as well as in the tube that feeds the steam faucet. You can clean the steam wand and tube by blowing compressed air backwards through the wand (with boiler cap off) and manually remove the screen to check for flakes.
Oh yeah, to scour the boiler....if you have big hands be extra nice to someone with small ones.

Thanks Doug for the info.

I spent the better part of yesterday doing what you suggested, I seem to have gotten most if not all of the coating flakes off and out of the machine via rinsing, shaking and re-heating cycles, without taking the boiler apart since I don't have a new boiler gasket handy. I will save that for another day when I get the new gasket set and refurb. the machine.

So, is there chemical like Durgol that can dissolve this stuff (my guess is no) or de-laminate it more quickly (use more citric acid)?

What I don't get is why they plated the inside, what does the plating do? prevent scale build up (doubtful) or corrosion? or just cosmetics?

And their own website instructs you to use citric acid, leave machine on to soak for 2 hours etc... I guess that only applies to the 2002 model with stainless boiler. What do you use to de-scale that won't take off this plating? too late for me, but it may help someone else.

- Steve.