An update: I'll first try a ***descaling*** as I'm pretty sure the last one was 8 years ago.
I had a look at the teardown guide, but the steam valve knob wouldn't budge. I'll try again.
On the picture, my machine doesn't have the parts circled in green and yellow (not sure what the green one does)
On another half-boiler from a SIN017 I had previously, I tried to un-screw the mushroom valve holder (red), to no avail. No matter how hard I tried, being with screwdriver, washer or provided tool, il wouldn't rotate. Hopefully removing it won't be necessary.
[image|3011275]