I’m in Austin, Texas (read; HOT) and am working in a small walkup café with window service.
We’re fairly high volume and
are working with a new 2 gr La Marzocco Linea PB ABR - the one with scaled built in. I’m looking for some input from anyone else working on this machine and hoping to compile some experience in this thread.
My current issue: An extracted puck will stick to the screen about 1 of every 3 shots extracted.
The ambient temperature doesn’t seem to matter much as it will do it very early in the AM and even before opening. A quick on/off of the continuous brew button will dislodge the puck, then I’ll unlock the portafilter and keep on as usual. It’s become a habit now, this little workaround, but occasionally that quick tap of the button isn’t enough and the puck still sticks. This machine is wonderful but this problem is very annoying and makes for a quick mess and fault in workflow if I’m not careful.
Unfortunately I don’t think it’s that simple. I dosed from 16 - 18 g in a 17g La Marzocco basket and had the same issue all day today. The issue also occurs with VST baskets.
I have a linea pb and it happens with that. Nothing I can do about it but check the basket as I take it out before I purge the group head. I dose lower with decaf and single than I do with the house blend and they all do it sometimes. But prob only a few times a day.
Used to happen before with my standard linea as well.
What size tamp are you using? I get pucks suctioning out of the basket and on the screen sometimes if I’m not careful when working with larger diameter (58.4mm+) tamps.
Used a linea pb for about a year and about 3 months ago we changed things up and also started having the same problem.
Before it happened we were using -
Approx 18 g dose in a 20g vst basket
94 degree coffee boiler temp (brew temp)
8.75 bar pressure
We changed our recipe due to a heads up by our main roaster who use the same equipment.
Aprox 16g in an 18g vst basket
91 degree coffee boiler temp
7 bar pressure
We clean the groups a lot more often (every couple of shots ) now by wiping the sides and back flushing with a blank screen - due to more grinds hanging around after removing the portafilter. But the change has been worth it giving a much more agreeable and delicious espresso, one of my colleges describing it as more of a filter style approach to espresso.
Someone I know puts the puck sticking to the down to using the smaller baskets. It could easily be one of the other variables. We like this recipe and don’t mind working around it. I’d suggest you either find a way to do the same or experiment with other parameters.
Also if you don’t find a solution, you might want to do what we do and take the portafilter out , hold it slightly below the group and catch the puck while flushing a tiny bit of water, instead of doing it while it’s fully locked in.
My current theory: your grinder is producing a lot of fines (not necessarily a bad thing). Those fines all travel to the bottom of the basket during brewing and create a dense layer right above the basket’s holes. When you stop the shot, the built up pressure is sucked backwards through the 3-way valve. Usually, air replaces that water when it’s sucked through the puck, but with a thick layer of fines is too dense for air to make it through fast enough, so the puck is sucked up.
Where can i learn more about espresso machine? iany channel or books about machine.
I have issue when machine turn on first early in the morning. The pressure gauge goes up to 15bars before it slowly come down 9 bars. How can i set it not goes to 15 bars. Just want max up to 12 bars? Is it this overpressure valve adjustment?
