Operation; Operating Principle - Ferroli Domina F 24-30 E Technical Manual

DOMINA F 24 - 30 E
FERELLA F 24 - 30 MEL
MILOS AIR COMPACT E

3. OPERATION

3.1 Operating principle

When there is a call for heating, the circulator and fan start working; then the air pressure switch enables
the control and safety unit to ignite the burner. Via the electronic flame modulation system, the boiler
capacity is gradually metered till it reaches the set delivery temperature. If the power needed for the
heating plant is lower than the minimum boiler power, when the delivery temperature exceeds the
setting of 6°C, the burner switches off and the electronic system enables re-ignition only after another
2 minutes. On reaching the set ambient temperature (room thermostat), the burner switches off and the
circulator keeps on working for another 6 minutes to enable better heat distribution throughout the
system. If hot tap water is drawn off during the heating phase, the electrical heating circuit automatically
turns off and the hot tap water production circuit switches on. Throughout this phase the heating system
circulator stops and the boiler delivers water at the set temperature.
The boiler keeps the tap water temperature constant by means of flame modulation, even when
different quantities are drawn off.
Test function
Bridging the terminals of connector X5 turns on “Test” operation. In this mode the boiler works as in
heating mode, but tap water operation, idle time and modulation are turned off. The test lasts 5 minutes.
We recommend opening 1 or 2 taps to get rid of the excess capacity.
Post-circulation
After the call for heating, the circulator performs "post-circulation" for approximately 6 minutes to
prevent thermal inertia and balance the system boiler temperature.
Circulator anti-locking
If not used for 24 h, the circulator is turned on for a few seconds to prevent it locking due to an extended
stoppage during summertime operation.
Gradual starting on heating (gradual increase in heating temperature)
The time to reach the maximum heating temperature is 5 minutes.
Limit thermostat
The 88°C limit thermostat coming on causes the burner to switch off momentarily via the ignition unit
and the heating circulator to start up.
Antifreeze protection
The antifreeze function is turned on by the heating temperature sensor when the temperature falls under
5°C. In this phase, both the burner and the circulator start working. When the temperature reaches 15°C,
the burner switches off while the circulator keeps on working for another 6 minutes.
Tap water circuit antifreeze protection (optional)
It is possible to ensure antifreeze protection for the tap water circuit with the antifreeze kit comprising
4 heating elements of 10W - 230V to be connected to terminal X2 of the control card.
Version - 09.2002
30
Supplied By www.heating spares.co Tel. 0161 620 6677