Product specifications

9
0 Pump overrun
After CH operation the pump has an overrun. This overrun time is set to the
value according to parameter 8 (see §7.3; factory setting is 1 min). This setting
can be changed. Also, 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.
1 Required temperature reached
The controller can temporarily block the heat demand and stop the burner. This
blocking takes place because the required temperature has been reached.
When the temperature has dropped sufficiently, the blocking is cancelled.
2 Self-test
The controller regularly checks the connected sensors. During the check, the
controller does not carry out any other tasks.
3 Ventilate (Fan)
On starting, the fan is first brought to the starting speed. When the starting
speed has been reached, the burner is ignited. Code 3 is also visible after
stopping the burner, when post-purge takes place.
4 Ignite
When the fan has reached the ignition speed, the burner is ignited by means of
electric spark ignition. During ignition the code 4 appears. If the burner is
not ignited, another ignition attempt is made after about 5 seconds. If the burner
has still not fired after the fourth ignition attempt, the controller indicates a fault.
See §8.
5 CH operation
An on/off thermostat can be connected to the controller, if necessary in
combination with an outside sensor. See the Electrical diagram §10.1 and
§10.2. When heat is demanded by a thermostat signal, the fan runs (code 3 )
and the burner is ignited (code 4 ), followed by the CH operating condition
(code 5 ).
During CH operation, the fan speed and hence the power of the appliance is
adjusted. This is done in such a way, that the temperature of the CH water is
controlled towards the set CH supply temperature. In the case of an on/off
thermostat, the CH supply temperature is set at the operating panel. In the
case of an outside sensor, the CH supply temperature is determined by the
weather dependent control programmed in the controller.
During CH operation, the demanded CH supply temperature is displayed on the
operating panel.
During CH operation, the actual CH supply temperature can be read by
pressing the service button.
Note: Instead of an on/off thermostat, an OpenTherm thermostat can be
connected to the controller as described in §5.3.1. In this case, the desired CH
temperature is set by the thermostat. The minimum temperature and the
operation mode can be set with parameters [E] and [E.] (refer to §7.3).