Check machine condition
Slim Jim Idrocompresso User manual
page 34
Check pressure gauges
1. No pressure: when not brewing, the
needles on all gauges should be in “resting position”
(indicating close to 0 bar).
2. Identical pressure: with a blind filter in all groups of a cold machine and brew-levers in locked
(down) position, the gauges should display identical pressures (line pressure). A small deviation
between the different gauges (0.2 bar) is within specifications.
3. On the lever version there is no procedure to check the gauges w.r.t. each other at elevated
pressure.
Note!
There is no need to replace a faulty gauge immediately. The gauges give feed-back on, but have no
active part in, the brew-process. A machine remains fully operational with faulty gauges as long as
they do not leak. Have a faulty gauge replaced during the next scheduled service.
Opening pressure of expansion valve
Each group has an individual expansion valve. The opening pressure of the expansion valve can be
checked by first having a long flush (about 20 seconds) then quickly locking in a water-filled blind filter
and pull the brew-lever into locking position. Expansion due to heating up the cold inflow of water will
increase the pressure inside the coffee system. The gauge should reach a maximum value between
10.5 bar and 13.5 bar and then remain constant.
Notes!
-
Remaining air in the group will make the test worthless. Perform a new test when the lever does
not feel firm when unlocked from lower position.
-
If the pressure rises above 13.5 bar (1) the expansion valve opens at too high pressure or (2) the
gauge is malfunctioning.
-
If the pressure does not rise over 10.5 bar it is possible that (1) the expansion valve opens at too
low pressure or (2) the one-way valve in the system is malfunctioning, (3) the relief-valve of the
group is leaking or (4) the gauge is malfunctioning.
When a malfunction as described above is encountered, have a technician solve the problem as soon
as possible.
Consistency in programmed volumes
The lever-
version of the Slim Jim does not make use of flow meters to account for “shot volume” so
consistency in the cup completely depends on barista-skills. Total volume of the cylinder is 55-60 ml
meaning that the moment the lever is unlocked, a maximum of 55-60 ml will flow through the coffee-
bed. If the coffee-bed is not completely soaked upon releasing the lever, up to 15 ml of water will
remain in the coffee-bed and thus not end up in the cup. It is advised to unlock the lever only after the
first drops of brew have fallen into the cup.
A brew can be stopped at any moment during a brew by shortly pressing the flush/relief-handle down.
Note!
Be careful when using the flush/relief handle to stop a brew, the brew-lever will quickly return to
resting position.
