I descaled the Machine 4 months ago, but somehow it wasn\'t enough for the Valve.( i use Brita filter for the water)
what is a mild descale ?, for me there is descale or No descale!

I am one of those people who try to avoid descaling, preferring to try to give the machines only good softened water. When I suspect that calcium might have deposited somewhere I like to mix up some descaler (On my own Giottos I usually use Urnex Dezcal) and mix it at 1/4 the strength that the package suggests. At work I use Skale Kleen at approximately 1/4 the suggested strength. Running this mild solution through doesn't give the machine much galvanic potential so I believe it's not stressing the dis-similar metals while it will still have a chemical reaction with the calcium and will come out cloudy if there's enough calcium in the crevices...

Then I have to decide whether I want to do a full strength descaling simply pumped through the circuit that needs it, or if I want to disassemble some parts and attack the individual deposits in a specific valve or at a restrictor in the thermosiphon loop or whatever the issue is.

i will soft descale it on the weekend and see what will go out

update:
Everything work perfectly after i cleaner the Valve, i did a soft descale as you recommended but wat did came out was really minimal.
thank you again for your help.

I especially love that dosing cup, but all of the wooden accessories are gorgeous... Hide that red knock box.