In case of excessive heat in the primary heating system, it is possible to dissipate this heat into the secondary heat consuming circuits. Primary heating generators can generate a heat override signal. In this case the DHWS setpoint will be increased by the value, as defined by the parameter SYS-02.
The maximum calculated DHW setpoint will be limited by anti-legionella setpoint LEG-01.
If the heat override signal becomes zero again, the DHWS setpoint will be ramped down to its normal value. The ramp down is defined as a decrease per minute defined by the parameter SYS-03.
The next figure shows the relation between the calculated setpoint and the heat override function.
The circulation pump will run during overheat protection staring without delay if the parameter SEP-04 = 3 or 4.
Fig. 6. Overheat Protection
Table 17. Parameter List
Description |
Range |
Default |
Units |
LEG-01: anti-legionella setpoint |
0...90 |
70 |
°C |
SEP-04: circulation pump during overheat protection 0; 1 = disable 2 = enabled if “MaxThermostat” = 1 3 = enabled if “OverheatProt” = 1 4 = enabled if “MaxThermostat” = 1 or if “OverheatProt” = 1 |
0..4 |
0 |
- |
SYS-02: setpoint increase at OverheatProt; 0 = disable |
0...30 |
10 |
K |
SYS-03: setpoint decrease/ minute after a Heat_Override |
1…100 |
5 |
K |