I'm planning a video showing how to pull the three main styles of espresso shot (Italian, Seattle, Third Wave). This will include coffee choices, grind settings, dosing, basket choices and machine configurations. Since the Bianca is so easy to reconfigure; I'll be able to shoot it in my one take, what director?, what storyboard? style. But it's still going to take a few weeks of planning to get done.

In the mean time, just loosen the little screw on the paddle. Open the valve until the paddle hits the machine on the right (this is about 40% open), then lift up the paddle and replace it on the valve stem so it is all the way left, and open the valve some more. IIRC, it will be full open after about 2 1/2 turns like this.

When you are done Seattling, turn the valve all the way off, and then reset the paddle so it is all the way to the left, and you are back to the factory set up for profiling, (or for E61 classic style shots with the paddle all the way to the right, and the valve about 40% open, operating like a group jet)

Here's a tech note: The water debit with the valve full open is about 12 mL/sec, it is 5 mL/sec with the paddle full right in the stock configuration (when paddle full left closes the valve completely). This 5 ml/sec is less than a standard E61's water debit (about 8 mL/sec), but since the pre-infusion spring is set much stiffer, the overall pressure ramp up time (with paddle full right) is the same. The lower water debit is required to make make the profiling system work; so the Lelit engineers stiffened up the preinfusion spring to keep the machine compatible with standard E61s with paddle full right. An alternative would be to have the regular preinfusion spring and have a valve that opens and closes completely in a half turn. But that would have screwed up the wonderfully precise control you get from the Bianca paddle (which in this aspect blows the LM, Slayer, Hydra, and Mina paddles away)

Here's a Mano note: to do the Seattle style shots, you also want to make sure you grind coarse, leave very little head space in the basket, and run the brew boiler a tad hotter, since the shots will take less time.

It sounds like a thermosyphon stall. One of the alt.coffee originals, Randy Glass, has a how to piece on it.

I'm curious, are you starting it from cold or from standby or while the machine is still hot. I'm asking because in a cold start, the firmware overheats the boiler, which gooses the thermosyphon.

I'm not sure. Flushing is the cure for occasional stalls; it happening often from cold starts is new to me. You may want to contact your service department. Lelit's engineers have been very responsive to bugs; and your vendor can contact them.