Intergas Heating Ltd
12
0
Pump overrun of CH
After the end of CH operation the pump continues to run. The running time is factory set at the
value in accordance with § 10.3. This setting can be changed.
In addition, the pump runs automatically for 10 seconds once every 24 hours in order to prevent
seizing. This automatic switching on of the pump occurs at the time of the last call for heat. To
change the time, the room thermostat setting should be increased briefly at the desired time.
1
Boiler shutdown when required temperature reached
The boiler controller can temporarily shut down the request for heat. The burner is then
stopped. Shutdown occurs because the requested temperature has been reached.
When the temperature has fallen sufficiently and the anti cycle time has passed the
shutdown is cancelled.
2
Self-test
The connected sensors are checked regularly by the boiler controller. During the check
the boiler controller does not perform any other tasks.
3
Ventilation
When the appliance is started the fan is first brought to starting speed. When the
starting speed has been reached the burner is lit. Code
3
is also visible when post-
ventilation is taking place after the burner has stopped.
4
Ignition
When the fan has reached the starting speed, the burner is ignited by means of
electrical sparks. During ignition the code
4
is visible. If the burner does not ignite, a
new ignition attempt occurs after approximately 15 seconds. If after 4 ignition attempts
the burner is not yet burning, the boiler controller goes into fault mode (See § 11.1).
5
CH operation
An on/off thermostat, an OpenTherm thermostat, an external sensor or a combination of
the latter can be connected to the boiler controller.
When a request for heat is received from a thermostat, the fan is started (code
3
),
followed by ignition (code
4
) and CH operating mode (code
5
).
During CH operation the fan speed and hence the appliance power are controlled by
the boiler controller so that the CH water temperature reaches the desired CH supply
temperature.
If an on/off thermostat is connected, this is the CH supply temperature set on the
display. In the case of an OpenTherm thermostat the desired CH supply temperature is
determined by the thermostat. In the case of an external sensor the desired CH suppply
temperature is determined by the heating line programmed in the boiler controller. For
the latter two, however, the maximum is the temperature set on the display.
During CH operation the requested CH supply temperature is indicated on the operating
panel.
The CH supply temperature can be set between 30°C and 90°C.
When the DHW comfort function is switched on (See code
7
) any OpenTherm request
for heat of less than the value of par. E is ignored.
6
DHW operation
The hot water supply takes priority over the heating. If the flow switch detects a need for
more than 2 l/min of DHW, any demand for CH will be interrupted. After the fan has
reached speed code
3
and ignition has taken place code
4
the boiler controller goes
to DHW mode code
6
.
During DHW operation the fan speed, and hence the power of the appliance, are
controlled by the boiler controller so that the DHW water temperature reaches the DHW
temperature setting.
The water temperature can be set between 40°C and 65°C (See § 10.1.6).
