Setting parameter SYS-03 = 1, the user has the option to hold the setpoint output for the leading boiler as long as the heat demand is higher than SST-05.
If this function is enabled, the setpoint will be the actual calculated heat generator setpoint.
The leading boiler always holds this setpoint value as long as the heat demand is higher than SST-05. If the boiler has a basic stage, this stage will stay on as long as the setpoint output.
The valve and pump will run not run during this special function.
The user has to assure that the external boiler controller controls the pump and valve.
The next heat generators in the sequence are controlled by the heating strategy.
If a following boiler is requested, both the basic stage and the setpoint output will be switched on directly. The setpoint output will not modulate, but keep the value equal to the heat demand + setpoint raise.
If the following heat generator is not needed anymore, it switches off directly.
Table 15. Parameter List
Description |
Value Range |
Default Value |
Unit |
SYS-03: leading boiler holds the setpoint output |
0/ 1 |
0 |
- |
SST-05: minimum heat demand to start heat generators |
0...150 |
20 |
°C |