Valves - LAVAZZA LB 4712 Maintenance Manual

Maintenance manual for technical assistance

8.2.3. Valves

once a year, at least, check the correct operation of the
safety valve, pressure relief valve and discharge one-
way valve.
When their replacement is needed, due to a malfunction,
retest the new valve installed.
carry out the tests in the following way.
Safety valve
First test:
- remove the upper grid of the ma-
chine;
- push the pin (1) downward with a
gripper;
- if the pin doesn't move, it probably
means that the valve is encrusted
with lime scale and should be re-
placed.
Second test:
- switch the machine off;
- open the steam valve and discharge the pressure in
the boiler;
- switch the machine on again and check the regular clo-
sure of the valve.
Pressure relief valve
First test:
- remove the upper grid of the ma-
chine;
- push the pin (2) downward with a
gripper;
- if the pin doesn't move, it probably
means that the valve is encrusted
with lime scale and should be re-
placed.
Second test:
- switch the machine off;
- tighten the set screw located on the pressure switch,
clockwise, completely;
- switch the machine on again and wait for the boiler
pressure to increase;
- check the correct operation of the valve at the maxi-
mum pressure of 1.9 bar.
Expansion one-way valve
- activate the brewing units for at
least 30 seconds;
- attach a filter-holder (3) with
pressure gauge to the brewing
unit;
- activate the brewing unit and
check the pressure increase via
the pressure gauge (4);
- check the pressure increase due to the expansion ef-
fect of the heated water until approximately 12 bar:
Manual code 10066846 / Rel. 0.00 / March 2012
when this value is reached there is the confirmation of
the correct operation of the valve and the sealing of the
gaskets and solenoid valves
- disable the dispensing;
- repeat the same test on the other brewing unit.
1
4
8.3. Cleaning
For perfect cleaning and efficiency of the appliance, se-
veral simple daily cleaning operations are necessary on
the functional parts and accessories as well as the body
panels. These operations must be carried out by the
user.
The indications given here are applicable for normal use
of the coffee machine. If the machine is heavily used
then cleaning should be performed more frequently.
It is recommended to always carry out cleaning with
2
completely clean and hygienic cloths.
Warning
Cleaning must be always carried out with comple-
tely clean and hygienic cloths.
Attention
Attempts at intervention inside the machine are
strictly forbidden.
Never use alkaline detergents, solvents alcohol or
aggressive substances.
During cleaning, be careful with the tips of the cap-
sule perforator located inside the clamping ring of
the unit.
8.3.1. Capsule-holder
clean the capsule-holders in hot water daily. leave them
immersed in hot water overnight so that the fatty coffee
deposits can dissolve.
Then rinse them.
3
21