30
•
System to prevent pump sticking
If there is not heating demands for 24 consecutive hours in heating
and/or domestic hot water mode, the pumps start to run automatically
for 1 minute. This function is enabled when the boiler is electrically
powered and selector (1) is not set at position (0).
•
Hydraulic safety valve (heating circuit) (i models)
This device, calibrated to 3 bar, automatically discharge the water when
the system pressure exceeds the set value. It is advisable to connect
a drainage to the safety valve.
THE USE OF THE SAFETY VALVE TO DRAIN THE HEATING
CIRCUIT IS STRICTLY PROHIBITED.
•
Regulation device for Domestic Hot Water temperature
This device sets the maximum temperature of the domestic hot water.
Its range is from a minimum of 5°C to a maximum of 60 °C. To
increase the temperature rotate knob (3) clockwise and vice-versa to
decrease it.
•
Anti - legionella function (with water storage tank)
At weekly intervals, the electronic controls of the boiler bring the
water of the tank to a minimum temperature of 60°C. This function is
activated also one hour after the boiler has been electrically powered
or reset, and in any event after reaching output requirements in heating
mode. This function is not enabled if domestic hot water knob (3) is
set to minimum or the DHW programming timer does not require
heat.
•
Anti - frost device (with water storage tank)
If the domestic water temperature control knob is set to minimum,
the electronic control unit will ensure that temperatures do not fall
below 5°C.
17. Check of the combustion
parameters
To measure the combustion efficiency and the hygiene of the products of
combustion in situ the boiler is equipped with two ports on the concentric
union that are intended for this specific purpose.
To access the ports, take the top cover off the boiler.
One port is connected to the flue gas outlet circuit by means of which
it is possible to measure the hygiene of the products of combustion and
the combustion efficiency.
The other one is connected to the combustion air intake circuit where it
is possible to check for any recirculation of the products of combustion
in the case of coaxial ducts.
The following parameters can be measured via the port connected to the
flue gas circuit:
• Temperature of the combustion products.
• Concentration of oxygen (O
2
) or in alternative of carbonic anhydride
(CO
2
).
• Concentration of carbon monoxide (CO).
The temperature of the combustion air must be measured, in the case of
coaxial ducts, at the port connected to the air intake circuit. In the case
of separate ducts, it must be measured in the zone in front of the burner
by inserting the measuring sensor on the silicone pad in the front box of
the sealed chamber (spark plug cable gland).
16. Regulation and safety
devices
These boilers are built to satisfy all the European rules and prescriptions
and in particular are provided with:
•
Automatic and electronic ignition
On demand of regulation devices, the PCB produces the spark at the
ignition electrodes and, opening the gas valve, causes the lighting of
the burner. At the same time the system checks the regularity of the
flame by means of the flame sensing electrode. If there is not flame
within the safety time, the boiler blocks and the red signal (8) start
to blink. Only after removing the problem it is possible to repeat the
ignition rotating selector (1) temporarily in position R.
•
Regulation device for the Central Heating water temperature
This device sets the maximum water temperature in the heating circuit.
Its range is from a minimum of 30°C to a maximum of 85°C. To
increase the temperature rotate knob (2) clockwise and vice-versa to
decrease it.
•
Electronic flame modulation
In relation with the position of the temperature regulation knobs (2)
and (3), the electronic control of the boiler regulates the gas pressure
to the burner depending on the real conditions of thermal exchange.
•
Air - flue gas pressure switch
This device permits igniting the burner only when the flue gas
discharge circuit is fully efficient.
When there is one of these faults:
•
outlet end-piece obstructed
•
fan jammed
•
“venturi” - pressure switch connection broken
The boiler will remain on standby and the warning light (10) will
blink.
IT IS FORBIDDEN TO DISENABLE THIS SAFETY DEVICE
• Safety thermostat
Safety thermostat, which sensor is positioned on the boiler’s heating
flow, stops the boiler operation in case of overheating of the water
which is in the heating circuit, due to an anomaly of the regulation
device. In these conditions the boiler blocks (red blinking signal 9
and 8) and only after removing the problem it is possible to repeat
the ignition rotating selector (1) temporarily in position R.
IT IS FORBIDDEN TO DISENABLE THIS SAFETY DEVICE
•
Pump post-circulation
The post-circulation of the pump, electronically obtained, lasts for
3 minutes after the room thermostat switching off (central heating
pump) or at the end of the DHW storage tank heating (sanitary pump,
Summer operation with water storage tank).
•
Anti - frost device (heating circuit)
The electronic controls of the boiler include a frost protection function
in the Central Heating circuit. This function lights the burner when
the flow temperature drops below 5°C and continues until the flow
temperature reaches 30°C. This function is active only if the boiler
is electrically supplied, selector (1) is not in position (0), and there is
gas.
