flamco MeiTronic W10, User Manual

Page: 72 / 232

72 Service setting manual
EN
LIQUID FUEL BOILER
For the required liquid boiler temperature, the highest temperature from the list below
is taken:
- calculated first stand-pipe temperature, increased for the value of parameter S5.3,
- calculated second stand-pipe temperature, increased for the value of parameter S5.4,
- desired d. h. w. temperature, increased for the value of parameter S5.5,
- calculated boiler temperature from slave controllers in BUS connection,
- calculated boiler temperature of an additional direct heating circuit.
The lower limit of the liquid boiler temperature is the minimum boiler temperature -
parameter P5.1, and the upper limit is the maximum boiler temperature - parameter
S5.1.
Burner control hysteresis is set with parameter S5.2. Burner switches off when the
boiler temperature exceeds the calculated boiler temperature for more than 60 % of
the hysteresis, and switches back on when the boiler temperature drops below more
than 40 % of the hysteresis.
With parameter S5.2 you can select an alternative burner operation mode:
S5.2=-1, inverted boiler output operation, without the use of the boiler temperature
sensor, S5.2=0, controlling the boiler without boiler temperature sensor, it is used to
start boilers with their own boiler controllers.
When there is no need for boiler operation, the calculated boiler temperature is 4 °C.
Due to the frost protection function, the need for heating (boiler start) can emerge in
the following cases:
- if the outdoor temperature drops below the set frost protection temperature -
parameter P1.3
- If the boiler temperature, stand-pipe or the room temperature drops below 4 °C.
CONTROL OF A TWO-STAGE BURNER
If you wish to control the two-stage burner, you need to set the parameter S4.9=3.
The first stage of the burner is controlled by relay R1, and the second stage is
controlled by relay R6, R7 or R8 depending on the selected scheme (circulation
output). The second stage is switched on, when boiler temperature drops 20°C below
the switch-on temperature for the first stage, or if boiler temperature remains below
the switch-on temperature for the first stage for more than 15 minutes and there is no
upward trend of the boiler temperature. The second stage is switched off when the
temperature in the boiler is less than 4°C below the switch-off temperature for the first
stage.
BASIC DESCRIPTIONS OF
CONTROLLER OPERATION