Vibiemme Domobar Junior - Manual (Page 7)

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4.3. Start up: grouphead
Vibiemme Domobar espresso machines is manual in its function with only one switch controlled by a lever
on the grouphead itself.
Here you see the Manual Control Lever on the right side of the E- 61 grouphead. It is shown in its at rest
position. This is where the lever should be whenever the machine is not brewing espresso
When the lever is lifted just past the first click stop the passive pre-infusion begins. This allows a slight flow
of water onto the coffee. This gentle flow of water wets the puck slightly which helps with extraction and
can also help eliminate channeling (disruption of the coffee causing a fast flow). If is not necessary to use
this position, but leaving it in this mode for about two or three seconds can be useful.
Lifting the Manual Control Lever to its full up position closes the 3-way valve and open the brewing path
between the heat exchanger and the coffee. At the same time, the cam to which the lever is attached
depresses the switch on the front of the Vibiemme Domobar espresso machines, just to the right of the
E-61 Grouphead, behind the cam. This switch activates the pump.
When you choose to end the brewing cycle, return the Manual Control Lever to its at-rest, fully down
position. Moving the Manual Control Lever to this position turns off the pump and opens the manual
3-way valve which is built into the grouphead.
This is a path from the grouphead down through the lower portion of the casting, and into the drip tray.
When it is opened it allows the pressure remaining in the brewing path to flow into the drip tray. This allows
you to immediately remove the Portafilter without worrying about the “portafilter sneeze”- that’s a spitting
out of coffee or hot water from confined pressure as can happen on lesser machines without a 3-way valve.
4.4. Start up: steam boiler pressure gauge
On the far left side of the panel is the steam Boiler Pressure Gauge (scale 0.5 to 2.5 bar). This displays the
pressure in the boiler which indirectly supplies you with the water temperature in the boiler. The higher
the pressure, the higher the temperature. While the machine is idling this gauge will move upwards when
the heating element is on, and will slowly move downwards when the heating element is off. Generally
speaking, a reading of about .9 to 1.1 should be expected. The gauge will fluctuate in a range of about
.15 in normal operation when the machine is idling (on, but not being used). Each division is .05 BAR (.73
psi). The Heating Element Activity Lamp to the left of the steam boiler pressure gauge indicates heating
element activity. When the Heating Element Activity Lamp is energized the lamp will be illuminated.
4.5. Start up: brew brew boiler gauge
The Brew Gauge on the right side of the display panel (scale 0 to 16 bar) displays the pressure in the
brewing path during an espresso pull. This gives a general indication as to what is happening during the
brewing cycle. The only time when the gauge will display any useful information is when the brewing
process is underway. At all other times, even when the pump is refilling the boiler, this gauge is not
displaying any useful information and should be ignored. About 9 BAR is a good place to be brewing as
you get started. Each division is .5 BAR.
To the left of the brew pressure gauge is the Low Water Indicator Lamp. If this is illuminated it means
that the water reservoir needs to be refilled and the machine will not operate until this task has been
completed. If the lamp is off, it indicates that the reservoir has sufficient water to operate.
To the right of the brew pressure gauge is the power indicator. This lamp is illuminated when the machine
is plugged into an electrical outlet and the machine is switched to stage I. The indicator lamps make it
easy to judge the machine’s state at a glance.