Cannot dial-in Breville Oracle Touch

[depth10]

I've had the machine for 2+ years and for the majority of the time it's sat unused (sad, I know) because I cannot get a decent cup of espresso to pull. I find that regardless of the beans I use, I find it not even extracting (at least a drop) unless I'm at 37 (out of 45 total on the grind scale). I've gotten it to OVER extract about a year ago and it looked watery, but even scaling it back to what LOOKED list the perfect pull, the coffee tastes very bitter.

I have operated at 197deg. since I purchased it
I even bought coffee that had been roasted in the past week to ensure freshness
I have not touched the tamp screw, left at default
I've descaled the machine and also used the cleaning tabs (we moved and I drained it, so I just turned it on and descaled it and cleaned it before use)
Just today after cleaning I got fresh beans, and started on 25 grind setting, then 30, then 35 (still not even a drop) and then 37 starting to pour after 10 sec and it it's set to a 25 sec pull.
It was very bitter
Found myself all the way at 45 (coarsest grind setting) and it only extracted less than an ounce!

I am really frustrated that I can't dial it in and I'm sure it's something I'm doing wrong.

Please help!

 

[shadow745]

Based on plenty of pros/cons often mentioned regarding the Breville Double Boiler/Oracle it seems that the Oracle should be quite capable if it's functioning properly. Many users have found the built-in grinder/tamping setup to be the weak link and choose to use an external grinder and dose/tamp manually. Your mention of such odd inconsistencies while trying to keep variables as even as possible I'd say you might have mechanical issues with the machine. Those things are known to have solenoid failures which can affect brew pressure as well as known serious issues after descaling. Hilarious that Breville often mentions descaling being mandatory, but didn't design the machines to handle it. Of course if balanced water is used to start with no descaling should be needed for most scenarios.

Even though I'll never rely solely on a brew pressure gauge, have you noticed any erratic pressure fluctuations during extractions? Any excess water ending up in the drip tray as a malfunctioning solenoid can often waste water in that sense?

 

[bullet08]

Try this. If you are loading a lot beans in the hopper, don't. If you are using 18 g for double shot, only put in 18 g. Use scale. If you use 18 g of beans, you should get 36 g out. You are looking for setup that will give 36 g at 27 - 30 sec. Once you get the grind in the PF, tap it few times so the grinds will settle in without empty space. Tamp with 30 lbs, evenly across the top and turn. Push on bathroom scale and feel what pushing down with 30 lbs feels like.

I have Breville Barista Pro, different machine. But noticed grinder grinds different amount than what I want when I have hopper full of beans. Loading only what you need for each shot gives better output.

Using scale and weighting output takes guess work out of the dial in.

Loading grinds in portafilter and doing that well is important. I tried different things and result will vary. You need to find one way of doing it and be consistent all the time. Tapping helps settle the grinds and possibly get rid of empty pocket. WDT tool might help.