1
Servicing and Maintenance
Product: Espresso-Machine
Model: Semi-automatic, Built-in
Service-Instruction: 1/04 Filter holder group head
(O-Ring)
Problem:
Liquid drips over the side of filter holder leaking out from between
filter holder and filter holder group head during coffee infusion.
coffee-brew should only flow out of the spouts on the lower part of the filter
holders.
Cause:
In the upper part of the group head there is the flange from which heated water
under pressure is forced through the tampered coffee during brewing. The flange
makes sure that the inner diameter of diffuser and filter holder group matches
the outer diameter of the filter holder. It is approximately 8-10 mm thick and has
a groove running around the outer edge which houses a gasket or seal made out
of heat-resistant, rubber-like material (O-ring) which normally prevents liquid
from leaking out between group head and filter holder. When the “O-Ring” is
defective or the wrong size, this can lead to the problem described above.
Solution:
The old gasket should be replaced with a new one following these
step-by-step instructions.
Safety Advice for Service Engineers
Attention: Before commencing any work on the appliance, it should be “disconnected”
from the electricity supply. This can be done by:
either removing the appliance plug from the mains socket or by isolating electricity
supply to socket through safety circuit-breaker or by turning off electricity completely
at mains switch.
As an authorised Service Engineer, you should comply with all European testing
standards and the relevant safety regulations for electrical appliances, in order not to
endanger yourself or other people and to prevent any other kind of hazards and risks.
