Westen NOVADENS BOYLER 240, Instruction Manual

Page: 25 / 152

5
96.091.1 - GB InstRUCtIOns FOR FIttERs
18. aDjUstMEnt anD saFEtY DEvICEs
This boiler has been designed in full compliance with European reference standards and, in particular, it is fitted with the following:
• safety thermostat
Thanks to a sensor placed on the heating delivery line, the thermostat interrupts the flow of gas to the burner if the water in the
primary circuit overheats. In these conditions, the boiler is blocked and only after the fault has been eliminated will it be possible to
light it again by pressing the reset button on the boiler control panel.
It is forbidden to disable this safety device
• Fumes thermostat
This device, positioned on the fumes evacuation duct inside the boiler, interrupts the flow of gas to the burner in case of temperatures
higher than 90 °C. Press the reset button on the thermostat, eliminate the fault and then press the reset button on the boiler control
panel.
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 the reset button on the boiler control panel to re-establish normal operating conditions.
• Hydraulic differential pressure switch
This device, mounted on the hydraulic unit, only allows the main burner to light if the pump is able to deliver the necessary head. It
protects the water-fumes exchanger if there is no water or if the pump blocks.
• 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.
• Frost protection device
The electronic boiler management system includes a “frost protection” function in the heating and DHW modes which, if delivery
temperature falls below 5°C, operates the burner until a delivery 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.
• anti-block pump function
If no heat demand is received in the heating and/or DHW modes for 24 consecutive hours, the pump will automatically start and
operate for 10 seconds.
• three-way valve anti-blockage function
If no heat demand is received for a period of 24 hours, the three-way valve performs a complete switching cycle.
This function is operative when the boiler is powered.
• Hydraulic safety valve (heating circuit)
This device is set to 3 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.