Technical data
37
Remarks
• The appliance has been provided with an electronic controller that
ignites the flame and continuously monitors this at each heat
demand from the heating system.
• The circulation pump starts running at each heat demand of the
boiler. The pump has an overrun time of 1 minute. The overrun time
can be changed if necessary. See Installer settings.
• The controller will automatically run the pump for 10 seconds, once
every 24 hours, to prevent it from getting stuck. This activation of the
pump takes place at the time of the last heat demand 24hrs later. In
order to change this time, set the room thermostat higher for a while
at the desired time.
• Step modulation is set to function (factory setting) so that the
power/speed is increased gradually from the minimum (parameter c).
This provides the best CH operation. However if the appliance is
being used only for heating an indirect hot water tank or for heating
fan convectors, the step modulation can be turned off. The appliance
will then start almost immediately at the maximum setting and the
system will heat up faster.
6.3 System Shutdown
CAU
TION
Drain the appliance and the system when the mains
voltage has been disconnected and there is a chance of
freezing.
1. Drain the appliance using the drain tap.
2. Drain the system at the lowest point.
6.3.1 Frost protection
• In order to avoid freezing of the condensate discharge pipe, the
appliance should be installed in a frost-free room.
• In order to avoid freezing of the appliance (heat exchanger), it has
an appliance frost protection. When the temperature of the heat
exchanger drops to 5ºC, the burner will be activated and the pump
will start running until the temperature of the heat exchanger
reaches10ºC.
• When the system (or a part thereof) can freeze, a frost thermostat
should be installed in the area to be protected. Connect this
according to the wiring diagram. See §10.1 and §10.2.
Note!
The external frost thermostat is not active when the appliance has been
switched off at the operating panel or when the mains voltage has been
interrupted.