Table of Contents
Advertisement
16. ADJUSTMENT AND SAFETY DEVICES
The boiler has been designed in full compliance with European reference standards and in particular is equipped with the following:
• Limit thermostat
Thanks to a sensor placed on the CH flow line, this thermostat interrupts the flow of gas to the burner if the water in the primary
circuit overheats. Under such conditions the boiler is blocked and only after the fault has been eliminated can it be ignited again
by pressing
.
• Exchanger flange thermostat (260°C)
This device is located on the exchanger flange and interrupts the flow of gas to the burner if the front insulation yields and
overheats the exchanger or the flange gasket develops a fault. Press the reset button on the thermostat, eliminate the fault and
then press the reset button on the boiler control panel.
• Thermal fuse
This device is located at the rear of the exchanger and interrupts the flow of gas to the burner if the rear insulation yields and
overheats the exchanger. If this device cuts in, dismount the exchanger and replace the thermal fuse (see paragraph "THERMAL
FUSE REPLACEMENT OF HEAT EXCHANGER").
It is forbidden to disable this safety device.
• NTC flue sensor
This device is positioned on the fumes duct. The electronic board stops gas from flowing to the burner in case of over heating.
Press
to re-establish normal operating conditions.
The above reset operation is only possible if the temperature is less than 90°C.
It is forbidden to disable this safety device
• Flame ionisation detector
The flame sensing electrode guarantees safety of operation in case of gas failure or incomplete ignition of the main burner. In
these conditions, the boiler blocks. Press
• Hydraulic pressure switch
This device allows the main burner to be ignited only if system pressure is higher than 0.5 bars.
• Pump post-circulation
The electronically-controlled pump post-circulation function lasts 3 minutes and is enabled, in the heating mode, if the ambient
thermostat causes the main burner to go out.
• Antifreeze device
The electronic boiler management system includes an "antifreeze" function for the heating and DHW systems which, when flow
temperature falls below 5°C, operates the burner until a flow temperature of 30°C is reached. This function is enabled when the
boiler is switched on, the gas supply is open and the system is correctly pressurised.
• Pump anti-block function
If no heat demand is received in the heating and/or DHW modes for 24 consecutive hours, the pumps will automatically start and
operate for 10 seconds.
• Hydraulic safety valve (heating circuit)
This device is set to 4 bar and is used for the heating circuit. Connect the safety valve to a drain trap. Do not use it to drain the
heating circuit.
• Heating pump pre-circulation
In case of a heat demand in the heating mode, the appliance can pre-circulate the pump before the burner is ignited. This pre-
circulation phase last from a few seconds to a few minutes, depending on the operating temperature and installation conditions.
The functions performed by the adjustment and safety devices are only operative if the boiler is switched on.
17. PUMP CAPACITY/ HEAD
The hydraulic pump is modulating and circulates the water between the boiler and the hydraulic separator.
KEY TO PUMP CHARTS - "SECTION" E
Q
RATE OF FLOW
H
HEAD
THE PUMP FLOW / HEAD CHARTS CAN BE CONSULTED IN ANNEX "SECTION" E AT THE END OF THE MANUAL.
to re-establish normal operating conditions.
19
7648477.03 (3-11/16)
Advertisement
Table of Contents
