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TECHNICIANS manual
8.3.3 Dispensing group maintenance
Every 3 months replace the perforated disk (
1
) and
the under cup seal (
2
) of the dispensing group (use only
original spare parts).
8.3.4 SAFETY
VALVE
check
The Pressure relief valve is one of the main compo-
nents for the machine safety. Therefore, it is important
to carry out the following checks:
First check:
t
Remove the top grill of the machine;
t
use pliers to pull the pin of the valve (
6
) upwards;
t
if the pin does not move, it probably means the
valve is encrusted with limestone and must be
replaced.
Second check:
t
Turn the machine off;
t
block the pressure switch contacts;
t
turn the machine back on and check for
pressure in the boiler to rise;
t
check for correct intervention of the
valve at a maximum pressure of 1.9 bar.
If you notice any malfunction, replace the valve. Use only the
Manufacturer's original Safety Valves.
1
2
6
8.3.5 PRESSURE
VALVE
check
First check:
t
Remove the top grill of the machine;
t
use pliers to push the pin (
5
) downwards;
t
if the pin does not move, it probably means the
valve is encrusted with limestone and must be
replaced.
Second check:
t
Turn the machine off;
t
open the steam valves and drain off all
the pressure from inside the boiler;
t
turn the machine back on and check
for regular closure of the valve.
If you notice any malfunction, replace the valve.
8.3.6 NON-RETURN DRAIN VALVE check
The not-return drain valve is an important component
for the correct operation of the machine. Perform the
check as follows:
t
Activate the dispensing groups for about 30
seconds;
t
attach a filter holder (
7
) with a gauge (available
on request) to the dispensing
group;
t
activate the dispensing group,
and use the pressure gauge (
8
), to
monitor the pressure as it increases
up to 8-9 bar;
t
check the increase in the pressure due to the
expansion of the heated water up to a value of
approximately 12 bar: reaching this value con-
firms proper operation of the
valve, as well as of the gaskets
and solenoid valves seal;
t
deactivate the deliveries;
t
check the other dispensing
groups.
If you notice any malfunction, replace the valve.
5
7
8
Содержание 1GR Series
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