Basic Description Of Controller Operation; Mixing Heating Circuit - Promatic WDC10B Manual

BASIC DESCRIPTIONS OF CONTROLLER OPERATION

MIXING HEATING CIRCUIT

Stand-pipe temperature calculation
The upper limit of stand-pipe temperature calculation is set with maximum stand-pipe
temperature - parameters S2.6 and S3.6, lower limit is set with minimum stand-pipe temper-
ature - parameters S2.5 and S3.5. Parameters S2.1 and S3.1 are used to set the influence
of room temperature deviation for the calculation of the stand-pipe temperature, and with the
parameters P2.2 and P3.2 you can adjust the parallel shifting of the heating curve.
Heating switch off
If the calculated temperature of the stand-pipe isn't at least a few °C higher than the room
temperature, the heating is automatically switched off. If the room temperature is not
measured and when the outdoor temperature approaches the required temperature, then
the heating is automatically switched off. The temperature difference at which the heating will
switch off can be increased or decreased with parameters S2.13 and S3.13.
At automatic switch off of the heating, a temperature of 4 °C is set for the temperature of
the stand-pipe and the circulation pump is turned off with delay - parameters S2.16 and
S3.16. With parameters S2.4 and S3.4 other possibilities for pump operation can be select-
ed.
Intensive - BOOST heating
With parameters P2.3, P2.4, and P3.3 and P3.4 you can define time and intensity of inten-
sive (BOOST) heating, which is activated at transition of time program from night to day
heating interval.
Liquid fuel boiler protection
If the liquid boiler temperature drops below the minimum boiler temperature- parameter P5.1,
the mixing valve will gradually begin to close.
In the case, where liquid boiler temperature exceeds the maximum boiler temperature - pa-
rameter S5.1, boiler protection is activated. At this point, the maximum boiler temperature
- parameters S2.6 and S3.6 is set for the calculated stand-pipe temperature. The protection
is deactivated, when the boiler temperature drops below the maximum boiler temperature.
Solid fuel boiler protection
If the solid boiler temperature drops below the minimum temperature- parameter P5.2, the
mixing valve will gradually begin to close.
In the case, where solid boiler temperature exceeds the optimal operation temperature, the
controller proportionally increases the calculated stand-pipe temperature.
In this way, boiler overheating is prevented and the surplus heat is discharged into the build-
ing.
If the solid boiler temperature exceeds the maximum boiler temperature - parameter S5.13,
the mixing valve gradually opens up to the maximum stand-pipe temperature - parameters
S2.6 and S3.6. The protection is deactivated, when the boiler temperature drops below the
maximum boiler temperature.
Heat accumulator protection
If the temperature of the heat accumulator drops below the set minimum heat accumulator
Service setting manual
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