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USER MANUAL
Speedster
page 10
Using the machine
Brewing espresso
The 3-way brewing lever on the right hand side of the machine (see figure 1, item 4)
operates the group valve and the pump. The lever can be fixed in 2 slots and thus has
three operating positions:
1.
Lever in upper (resting) position: Group valve is closed and pump is off. Water
cannot flow from the coffee boiler to the coffee bed.
2.
Lever in middle position: Group valve is open but pump is off. In this position
(hot) water under line pressure can reach the coffee grounds which will wet and
swell. This process is called pre-infusion. You may adjust the timespan of pre-
infusion to your liking.
3.
Lever in lower position: Group valve is open and pump is activated. The water
pressure on the coffee bed will increase to 9 Bar.
Switching off is easily accomplished by a short down-right tap on the left hand ball on the
lever. The lever will return to its resting position and the remaining pressure in the coffee
filter will be discharged.
When you switch from resting position directly to the lower position, the primary
increasing pressure is absorbed by a piston and spring within the so-called “progressive
pre-infusion cylinder” up to approximately 3 Bar. As soon as the piston reaches its
ultimate position, the full pump pressure of 9 Bar is applied to the coffee bed. You can
easily check the functioning of the progressive pre-infusion as the guiding rod of the
piston will protrude through an opening in the front panel of the machine just left of the
hot water tap (see figure 1, item 9).
The extraction can be further manipulated by switching the lever from lower to middle
position near the end of the extraction phase. Water pressure will then decrease fairly
quick to approximately 3 Bar but remains at that level.
The progressive pre-infusion cylinder has the extra advantage that clean water in the
cylinder is pushed through the group valve into the discharge after each extraction, thus
rinsing the valve.
Note
Filling of the steam/hot water boiler is disengaged during brewing (brewing lever in
middle or lower position) in order to prevent differences in extraction pressure.
Hot water
A three-way toggle switch, located on the right hand side between the brewing lever and
the hot water spout, controls the hot-water distribution (see figure 1, item 5). The tap
knob itself (see figure 1, item 8) is purely visual and has no operational function.
When the switch is pushed downwards the machine will automatically mix a small
amount of cold water with hot water from the steam boiler. The main advantage is that
the result is a steady, non-sputtering, flow of hot water. The addition of cold water has
as extra advantage that less water from the steam boiler is used for the same amount of
liquid thus diminishing the load on the steam boilers heating element.