What other comparables, preferably at a lower price point than the Bianca have a thermo siphon to regulate the group?

Maybe I'm missing something. Seems like I read the Bianca was doing something different that regulated the group better than other e61's

The Lelit Bianca is a dual boiler machine, so you do not need to do anything special to keep the group at the right temperature.

The Lelit Mara X is a heat exchanger machine, and these have a tendency for the group head to overheat. The Mara has a unique solution to this problem by having a thermostat cycle the steam boiler between 0.8 and 2 bar depending on the group head temperature. This can make for odd steaming, but does mean you can walk up to the machine and pull a shot without worrying about the temperature, or needing to flush the group.

I think that must be what I was thinking of.

Vbm domobar super electronic
Ecm synchronika

diungerich wrote:Maybe I'm missing something. Seems like I read the Bianca was doing something different that regulated the group better than other e61's

The "flow control device" not being an option is the only obvious difference from the marketing standpoint.

Bianca comes with the Flow Control Device installed, rather than it being an option. That's just a needle valve installed where the gicleur would be in other E61 machines. It allows the operator to change the size of the orifice in the gicleur so that the coffee prep (The "puck" of ground coffee in the portafilter basket) isn't the only variable restriction to flow in the brew circuit. By adjusting the Flow Control Device while the machine is brewing, the operator can restrict flow in the beginning to give the coffee a very gentle pre-infusion. Then flow can be ramped up to get the extraction flow going without hitting the puck with a jolt and possibly disturbing the tamping. Then the flow can be tapered off to imitate the reduced spring force of a traditional lever machine coming to the end of its extraction.
Or, to explain in simple terms. Having a flow control device on the brew circuit is like having a throttle on a car. You don't have to drive with the extreme of either running with the gas pedal to the floor or the other extreme of engine off... You have a whole lot of control in the grey-area in-between, it's a needle valve, not a butterfly valve, but it's doing the work of a throttle, like a car's, to the water flowing in the brew circuit rather than the car's intake manifold.

That said. The Flow Control Device, that made the Bianca "new and different" than other 2-boiler E61 machines, is now available on most E61 clones worth looking at.

Further: The Flow Control device is only having an effect on the machine while actually brewing, it has nothing to do with the machine's thermosiphon loop and the heating of the grouphead. The thermosiphon loop is moving the hot water toward and down the outside of the "Mushroom" while the flow control is regulating flow into the inside of the mushroom... And jeeez am I ever getting further and further from the "Topic: Lelit Bianca Comparables" with the focus on the thermosiphon.

So, beginner class in thermosiphon:
An E61 head is mounted to the front panel of the machine and would cool off if not heated in some way. It is a darn heavy piece of machined brass and would conduct all of the heat out of your brew water before the water got to the coffee-prep if the machine didn't keep the brew head warm.
So. The E61 head has two ports connecting it to the machine, like radiators in your home have an upper and a lower pipe connecting them to your boiler. The hotter water in the boiler is hot and therefore lighter than the cooler water in the plumbing, so it is easy for the hotter to flow upward through the heating system in your house while the dense, cooler water flows in from below to replace it. Now imagine the brewhead with 2 ports and the coffee boiler with two ports. There you have the idea.

Other machines have the brewhead so integral (like basically the lower half of the boiler IS the brewhead) that it stays heated that way. Or there are ports and passages ensuring that the brewhead is "Saturated", fed a flow through some passages keeping it heated, so that the brew water path doesn't lose heat when brewing.

I know that was too many topics, but i hope it helps you understand a little about Thermosiphon and how it's a way to keep a brewhead warm, vs. Flow control which is a tool for the barista or operator to have more control over the machine. Neither of which are saying anything about a Bianca's pros and cons.

There are a lot of much cheaper machines on the market if you're interested in something with a thermosiphon circuit for the lowest possible price. Both ECM and Quickmill both have Single Boiler, Dual Use machines with E61 heads on them. Lelit may, also. But, you know, you get what you pay for. There are a lot more important things to consider than whether or not a machine is using a thermosiphon loop to heat the head. If you are going for a SBDU, consider anything cheaper than an E61 SBDU, also.

I see now, this is stupidly long.
I think you'd better ask your next question so I can see how far off topic I have wandered.

Hooray... I've not shut up, yet! Sorry...

If you are considering E60, 2-boiler machines, but you don't want to give them good, softened water, I suggest choosing something other than the Bianca. As interesting as the Bianca is, you have to consider that the inlet valve and the boiler-fill valves are positioned right at the top of that "arch" of plumbing where they will be able to dry out. Biancas that are given crappy water need to have the inlet valve cleaned/descaled/replaced more often than machines that don't have a superflouous inlet valve and can't possibly need such a thing. If you're considering a decent machine, consider looking after it.

Now I'll shut up.