I’ve had a Gaggia Classic for a few years and over the last few months I’ve been having issues with the flow from the group head.
I think it might be an issue with the solenoid valve. There was some guidance I saw online about flicking rapidly from the group head to the steam wand, as this forces water through and clears any blockages. And yes this does seem to work - if I rapidly flick the switches the water suddenly flows a lot faster from the group head. But it’s not a permanent fix.
I’ve descaled it several times. Is there something else I can do, or does the valve need replacing?
Would you use 50/50 distilled to tap water for example?
There’s a bunch of deep dives on water chemistry, but I mix third wave water packets into one gallon of distilled water.