4.2.5
System in cascade
Fig.10
MW-5000719-3
The boiler is ideally suited for a cascade system configuration.
Use a boiler/cascade connection kit to connect boilers in cascade.
4.2.6
Settings and safety devices
Important
The settings and safety devices are only operational if the boiler is
powered up.
Tab.11 Description of the safety devices
Device
Description
Safety thermostats
The safety thermostats suspend the supply of gas to the burner if the water in the pri
mary circuit overheats. To resume normal operation of the boiler, eliminate the cause of
this interruption.
Caution
The safety thermostats must in no circumstances be switched off or
disconnected.
NTC flue gas sensor
The control panel blocks the gas supply to the burner in the event of overheating. To
resume normal operation of the boiler, switch off the boiler and switch it back on again
with the ON/OFF switch.
Flame detector by ionisation
The boiler is put into safety lock-down in the event of gas shortage or incomplete cross-
lighting on the burner.
Hydraulic pressure switch
Thanks to this device, the burner can only operate if the installation pressure is higher
than 0.1 bar (0.10 MPa).
When the pressure switch detects a pressure lower than 0.8 bar (0.08 MPa), a warning
message is displayed, without stopping the circulating pump.
Post-circulating pump
After the burner stops, depending on the room thermostat setting and if in heating
mode, the circulating pump runs for a further 3 minutes.
4 Description of the product
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