CaffeRoma wrote:I got mine about a month ago, but have not really had the time to fully delve into the details of the machine. With the many questions I'm sure we will all be sharing in the next few months, the one thing that I have noticed is that the steam pressure (pre-set to 1.5 bar) drops off to 0.5 and then zero pretty quickly. I can really only steam single cappuccino amounts of milk maintaining a 1 - 1.5 pressure level. If I try to do two latte's at once it is takes much too long and the steam pressure is at zero for the latter part of the process.
Anyone else experiencing this? Should I be adjusting the steam pressure-stat for this?
THANKS!

Hi All,

After 2 days of working with our programmers, etc to resolve server crashes, software crashes, etc... I just had some time to add some feedback on this as I just pulled out the test unit formerly slated for HB and now slated for the SCAA show in MN.

To address the steam concern, I came accross the following conditions and results...

a) Steam boiler pressure was initially set at 1.9 bar. Machine fully warmed up to operating temp for both boilers.

b) Started with 12 ounces of cold water from faucet. The first instance instance had 2 minutes of steaming capability where it brought the water to a boil. The needle did nose dive to about 1 bar and then went and hovered near .4 to .5. until the water refill kicked in at 2 minutes and 5 seconds - at which point the steam pressure gauge needle nosedived to zero. In the second instance, the water came to a boil in 1 minute and 45 seconds. Again, the steam zeroing out at about 2 minutes.

c) In both instances, the recovery for the steam boiler was about 1 minute to 1 minute and 10 seconds.

d) In both instances, i did not measure the initial temperature of the cold water. our inventory shows 300 thermometers in our warehouse, and since we just moved, I can not find one! however, i did start steaming when the steam heat cycle was at the max of 1.9. The min level was about 1.5 to 1.6.

e) The steam is dry (similar to Vibiemme's HX machine).

I have already emailed Vibiemme about these results. i do not think there will be a problem bringing up the steam boiler bar pressure to 1.9. I am not sure where the safety valve on the steam boiler kicks in to release steam. So, please do not go higher than 1.9.

Now, results can vary from machine to machine as voltage (in your outlet can range from 100 volts up to 125 volts on a standard outlet), ambient temp differences, steaming pitcher temp differences, water temp differences, etc can impact these results.

It is now 9:22 pm est, and I need to get out of this office!

ira wrote:If you use a thermostat for the steam boiler the heating element won't likely turn on the instant you open the steam valve and you might find the steaming abilities slightly reduced.

Ira

I will confirm that the machine will have a slower reaction tiime to turn the steam boiler's heating element 'on' with a thermostat.

Tore the machine apart a bit more tonight to fix the Sirai bracket and took a few more pics.

The german reseller Systermann is using 2.5 bar for the steam boiler, so this shouldn't be an issue.

http://www.kaffee-netz.de/marktpl...-2.html#post197203

1st-line wrote:I will confirm that the machine will have a slower reaction tiime to turn the steam boiler's heating element 'on' with a thermostat.

I overlooked the fact the steam boiler is in the physics phase of saturation. As long as there is enough steam to remain saturated temperature will probably hardly drop, rendering thermostat controlled steam boiler inappropriate.

Regards
Peter
Netherlands
Europe

networkcrasher wrote:Tore the machine apart a bit more tonight to fix the Sirai bracket and took a few more pics.

Based on earlier comments, I would say the small boiler is the steam boiler and the large one the brew boiler.
For one thing this might be an explanation, but at this stage wild speculation.

Other than pressure, there is another variable I would relate to steam capacity, still: steam boiler water level.
I would think a high level leaves less volume (cubic centimeters) for steam, but, considering someone in these fora uses avogadro for web name, I might be taught a lesson in physics here, proving this is not so relevant. Still, steam boiler water level would be relevant in another way: re-heating response time to pulling steam. Would a larger amount of (liquid) water - higher level - provide more thermal buffer? I guess so, but it might take more time, once temperature dropping, to reheat the water to steaming temperature and related pressure.

Going back from this discussion to the machine's innards: the Cigar brainbox shown in the photos connects to the level detector (Liv) and pump (Pompa). Following the Liv wire to the level detector on the steam boiler you get to a metal insert on top of the boiler with the sensor in the middle to which the wire connects. I believe that level meter can be adjusted for the depth of the actual sensor. (somewhere else I read a warning about replacement of the wiring harness and taking care not to change the depth of the sensor which would easily change when pulling off the wire on it.)
All these Italian machines are system integrated generally from in-sourced prefabricated parts. They will do alternating series of their models. In the case of my own QM espresso machine, a new employee had assembled the water tank (magnet float, guiding channel, stop to keep magnet in front of solenoid switch when enough water). He was not aware the height position of the screw to keep the guiding channel in place was important - the machine did not come on with the water tank filled more/less than exactly the position of the solenoid.

In other words, did they maybe do a series of these machines with the level sensor in too deep or not deep enough? And are you trying to work around that by raising the pressure?

Regards
Peter
Netherlands
Europe

Safety valve are calibrated to open at 1.8 - 2 bar ( depending on which one you have ). The compact style safety valve ( with blue sticker in top) is calibrated to open at 2 bar.

I do not recommend adjusting any pressurestat any higher then 1,5-1.6 ever