Troubleshooting Rocket Appartamento fluctuating brew pressure - Page 3

Equipment doesn't work? Troubleshooting? If you're handy, members can help.
DGlover (original poster)

#21: Post by DGlover (original poster) »

Spoke too soon - problem is back and that's after replacing the in-line filter.

Will start with the S2 valve and work from there.

captjimmie

#22: Post by captjimmie »

Any progress? I have nearly the exact same problem with my appartamento. Thanks!

JRising

#23: Post by JRising »

Well, how close to "The same"?

If your pump is stalling, and can't resume until the downstream pressure drops below 8 bars, don't waste your time, replace your pathetically weak pump. If it's not the same at all, then what are your symptoms?

captjimmie

#24: Post by captjimmie »

Bouncing pressure and surging pump, 4-8 Bar. Dead-heads to 10 Bar with blind basket, steady. Looks very similar to OP's initial video. Interesting how it appears to have trouble maintaining a constant pressure against a puck (pressure with flow) vs dead-heading.

JRising

#25: Post by JRising »

If a pump is strong enough, it won't stall until well above brewing pressure. Similarly it won't have trouble getting started, even against a back-pressure. If the OPV and Expansion valves are working, then it will never truly dead head because there's always a place for the water to go.

You can shut off the Pump's OPV to test or set the pressure of the expansion valve using the pump as the supply. Ensuring that all valves work is as important as ensuring that the pump is able to exceed them. Clean them and if they still don't open at 9.7 and 12 bar, replace them. If your pump can't exceed the pressure needed to open/test/set them, replace the pump.
The machine is made out of mostly wear and tear parts, it is doing what it can to provide you good espresso, keep up with its needs, too.

captjimmie

#26: Post by captjimmie »

Thank you for the reply. Yeah, I just meant deadheading as in pressure without flow. Tore apart the OPV, or as Rocket calls it the expansion valve. Cleaned up and appears to be working. Adjusted the pressure to 10 Bar into the blind basket. Guess I'll try the S2 valve and the non-return valves next. I'm beginning to suspect the pump after all. Adjusting the Expansion (OPV) valve down hard, can't get the pressure above 10 Bar, with only a very small drip of flow out of the expansion valve. thanks.