Setting up the GS3 - Part I
I guess the weight difference between the production and the prototype GS3s is mainly due to the plastic side panels vs. the aluminium ones on the prototypes. The drip tray is also made of plastic with the exception of the outside finish and the cover (vs. all stainless on the prototypes).
As I mentioned earlier, the water reservoir is now in the base of the machine instead of being an integral part of the machine's chassis (as it was in the prototypes). To get access to the reservoir, one has to remove the drip tray, which is easy, and slide it out. You then pop open the fill cover and pour in the water. The reservoir takes 3 liters of water while the drip tray actually takes a bit more than this (I think).
The downside of the GS3's reservoir setup is that you cannot completely remove it for cleaning and you have no visual clue as to how much water you have left. The machine does remind you on its display of the need to refill, though. Also, the machine appears to be very sensitive as to how one re-inserts the reservoir (it doesn't necessarily recognise that it is in and continues displaying the "refill tank" reminder).
After filling the reservoir, I plugged the GS3 in and hit the main power switch (located at the back of the machine). One can then switch the machine on from the keypad and the autofill kicks in to fill both boilers. This happened surprisingly quickly and the machine started heating up.
As the saturated grouphead is an integral part of the brew boiler and also the highest point in it, this is where air ends up. One therefore has to bleed the air out much like one does with the radiators in the house. I opened the valve shown in the picture and ran the pump until water appeared from the valve. Then close the valve and replace the cap on the grouphead and you are more or less good to go.
I say more or less, because there are almost endless opportunities for tweaking the settings. I chose not to touch those initially apart from trying to change the "name" of the machine shown on the display. However, I noted that this didn't really work too well. I tried setting the name to "Teme's GS3", but the machine did not want to display this correctly. When trying to change the name back to the original "La Marzocco GS/3", the display does not show this correctly, either. A bug in the software?
Anyway, once the GS3 is fully heated up, the keypad lights up in a nice blue backlighting. The steam boiler settled to a max of 2 bar as specified in the manual. The steaming power is not on par with e.g. the FB80, but I am happy for this as I found the full blown commercial machines too strong for small quantities of milk (i.e. for home use). However, there is significantly more power than on my Andreja. The steaming tip is a four hole affair.
I then put in the blind filter to check what the brew pressure setting was. It topped off at just over 5 bar. No good. I assume that this setting is for when one direct connects the machine to a water line and the line pressure combined with the pump setting provides the appropriate brew pressure. I may be wrong. Nevertheless, I need to find a way to tweak the setting and the manual gives no clue on how to do this (and there aren't too many people around who can help me during the weekend). I tried removing the side panels to have peek inside (and to take a pic to see if anyone on the forums could help figure this out), but couldn't get them off. It looks like I will have to wait at least until tomorrow before I can brew a shot...