Hi, I've had a used Gaggia Classic (2016 model) for a few years, and I can usually get it to produce a good espresso, but it seems like it goes through phases where the temperature gets really hot? I'm judging by how hot the espresso is when it comes out.

I've read up on Gaggia temperature surfing but the guidelines I've read elsewhere don't seem to apply to this machine. Sometimes it gets really really hot if I let it warm up for more than 10 mins; almost like it's mostly steam coming out of the grouphead. When it gets like that the espresso is, no surprise, awful tasting. Then if I run water through, it gets too cold and I can't figure out how to eyeball that Goldilocks temperature.

does anyone have tips on temp surfing a Gaggia?

I wonder if your brew thermostat has failed? The brew stat should turn the heaters in the boiler off when a certain max temperature is reached. If it's not doing that, the temperature will just continue to rise. It's an inexpensive part to replace, and would at least eliminate that possible reason you are having so much trouble.

Oh that's a good idea, would not have thought of it myself. I will give that a try thanks.

Just wanted to share that replacing the brew thermostat did fix the overheating issue! Thanks a million.