Liquid Fuel Boiler; Heat Pump - Promatic WDC10B Manual

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 tempera-
ture 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.

HEAT PUMP

Control of heat pump in schemes 422, 422b, 422c and 422d
The heat pump (HP) has 2 operation modes, depending on parameter S6.14 setting:
 S6.14=1 - HP is activated whenever there is a demand for heating and remains
switched on at all times. If outdoor temperature drops below the limit outdoor temper-
ature, set with parameter S6.17, HP is switched off.
Service setting manual
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