La San Marco 20/20 CLASSIC Series, Use And Maintenance

Page: 41 / 104

40
ENGLISH
As indicated in the following figure, depending on the
pump model supplied with the machine, this screw can
be adjusted in three different ways:
- Adjust the screw only
- Adjust the screw and lock it with the lock nut
- Unscrew the cap nut and adjust the screw.
5.3 Boiler steam pressure regulation
The steam pressure in the boiler is shown on the upper graduated scale of the
pressure gauge B (figure 13). The lower graduated scale indicates the ope-
rating pressure of the pump. To change the pressure of the liquid-saturated
steam mixture inside the boiler, you will need to vary the temperature as
explained in the programming chapter.
5.4 Brewing group temperature regulation
In models 2020 CLASSIC (except for models 2020 CLASSIC DTC) it is possible
to adjust the brewing temperature of the espresso coffee without altering the
internal boiler pressure. A valve (flow variator) is positioned at the top of the
HSPVQXIJDISFHVMBUFTUIFþPXPGIPUXBUFSDPNJOHGSPNUIFFYDIBOHFSTUIJT
valve is accessible from the top part by removing the cup support tray. Above
each group there are four numbered notches
2-3-4-5 (figure 14), the valve is
OPSNBMMZQPTJUJPOFEPOOVNCFS UIJTJTUIFEFGBVMUTFUUJOHCZ-"4"/."3$0
SPA). If you want to change the serving temperature, you will need to use the
valve (flow variator) of the group. To increase the temperature, turn the valve
towards the higher numbers. Contrarily, to decrease, turn the knob towards
lower numbers.
Figure 14
6. Operating instructions
%VSJOHUIFEFMJWFSZPGFTQSFTTPDPGGFFUFBPSTUFBNUIFTFTVCTUBODFTDBODBVTFCVSOTEVFUP
accidental skin contact.
Each brewing group has a keypad with 5 buttons (four for programmed coffee doses, one for manual coffee
doses).
Make sure the coffee is brewed in the cup as desired. If the result is not as desired, see the “Troubleshooting”
chapter.
6.1 Espresso coffee brewing
1) Remove the portafilter from the brewing group and fill it with one dose of ground coffee (single portafilter)
or with two doses of ground coffee (double portafilter).
2) Press the ground coffee using the relative coffee tamper and then hook the portafilter into the brewing
group.
3) Place one or two cups under the delivery spouts. Brewing is always enabled and does not depend on the
temperature in the boiler or the level of water in the boiler.
ADJUSTMENT SCREW