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80
AST 14 C 255/00
AUTOMATIC FILLING FUNCTION
Automatic filling is enabled only if parameter P94 is set to 1.
When the function is disabled, only the system pressure is controlled (with proper
signalling in case the pressure is too low), whereas, when it is enabled, the filling will be
carried out according to the following values given in the super-technical parameters:
SUPER-TECHNICAL PARAMETER
RANGE
DEFAULT
VALUE
NOTES
P10
Filling pressure ON and low water
alarm (E04)
0.4 ÷ 1 Bar
0.4 Bar
P11
Filling pressure OFF
1 ÷ 2 Bar
1 Bar
P12
Filling time
10 ÷ 150 sec
60 sec
When this time has
elapsed, the boiler
triggers E08 alarm
P13
Indicates that pressure is too high
(E09)
2 ÷ 4 Bar
2.8 Bar
P14
Alarm E09 reset
1.8 ÷ 3.8 Bar
2.6 Bar
P15
Alarm E04 disappeared
0.6 ÷ 2 Bar
0.8 Bar
P16
Max. number of filling attempts in 24h
1 ÷ 10
3
After successful attempts
Activation condition
The function is automatically activated in case the system pressure (as read by the
pressure transducer) falls below the threshold set by parameter P10 and at the same time
there is no signalling of the errors (respectively E04 and E08) relevant to the max. number
of filling attempts reached within the 24 hours (P16) or to the exceeding of the maximum
time for each single filling cycle (P12).
After checking the activation status, the solenoid valve is supplied with power for a time
equal to P12. To avoid disturbances during this operation, the boiler pump (if operating) is
stopped and the three-way valve is set to the "DHW" mode. Any request function is left in
stand-by mode.
Switching off condition
The function is completed successfully when the system pressure reaches the pressure
set by P11 within the time set by P12. If this is not the case, the "false attempt" is
memorised to avoid any further filling and the error E08 will appear on the boiler display.
WARNING: when the boiler is in the error E08 condition, the standard operation requests
can anyway be fulfilled provided that the system pressure has reached the pressure set by
P15.
Faults
The faults relevant to automatic filling, according to their priority, are listed below:
1) E04: too low pressure (pressure lower than P10 or max. number of filling attempts
reached within 24 hours);
2) E08: filling failed (failure to reach the filling pressure in a single attempt);
3) E09: too high system pressure (higher than P13).
