I thought someone might know here. I tried googling but couldn't find the answer.
I have just upgraded from a Gaggia Pure to a Classic. I bought it used as want the old aluminium boiler.
To start off with, the machine wouldn't pull a shot, water simply drips out of the splash screen. I stripped it down and gave everything a proper clean. It seemed unnecessary as the machine is very clean internally. It worked perfectly after I rebuilt it.
I then adjusted the OPV valve to 10 bar and fitted a Rancilio Silvia steam wand which made it a very good machine compared to the pure. However, the problem returned this morning (around 2 weeks since a clean).
I decided to measure the pressure with the pressure gauge attached to the portafilter. It started off with next to no pressure. However, around 30 seconds later, the pressure started to build very slowly, then up to the 10 bar which I have adjusted it to. The machine then returned to normal.
I suppose measuring the pressure is effectively giving a backflush which might cleaned out the solenoid valve. However, I only used it for a double everyday for 2 weeks with filtered water so the machine shouldn't need cleaning yet. Anyone know what is happening?