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?
I don't know the Gaggia, but on my Micro Casa I take the head group apart every few years and clean it. A surprising amount of buildup clogs the head. Can you take that apart and get the screen out to clean it?
It's part of the recommended regular maintenance in the instructions of my machine. I've not noticed any build up since I've been using a puck screen. I still have to take the thing apart to grease it every couple of years, but the group head has been much more clean.
If you do get it apart and cleaned, and it does help, and you're not using a puck screen, I recommend getting one to help keep the head clean. They're cheap.
Yeah it might be a good idea to take it apart. I don't think the head or screen is the issue, as once the water starts flowing (after using the switching trick) everything flows well through the head. I'll have a look into puck screens though!
I wasnβt using the correct water, and after about two years I needed to replace my valve. After inspection my boiler was also beyond descaling and the steam valve was drippy. I replaced those parts because I could but only the solenoid valve was required. FWIW there are videos on how to clean the valve (after removing it) but they didnβt work for me.
I used this, but Iβve installed the shades pid, shades pressure gauge, and a dimmer mod so I was fairly familiar with the innards.
Consumer carbon filters donβt really remove enough hardness to be effective. For convenience I use distilled gallons and third wave espresso packets. There are cheaper methods though.
Do the flick back and forth thing WITH the descaling goop. A lot. Wait a couple minutes. Do it again. Repeat and repeat until someone complains about the noise.