The domestic hot water will generate a priority request signal if all of the following conditions are true: the priority function is enabled by setting parameter SYS-04 >0 (SYS-04 = temperature drop for DHWS priority request)
Fig. 5. DHW Priority
The primary heating generators will receive the priority request and will force the "Domestic Hot Water Priority" signal to switch on. The heating circuits will control at a lower setpoint in order to consume less heat, which is then available for a faster heat up of the domestic hot water system. If the system flow temperature or the buffer upper water temperature exceeds the limits specified above, the "Domestic Hot Water Priority" signal will be switched "off" again. An overheat protection signal from the heat generators has a higher priority than the DHWS priority request.
Table 14. Parameter List
Description |
Range |
Default |
Units |
SST-01: temp. difference primary/ secondary system |
0...60 |
10 |
K |
SYS-04: temperature drop for priority request; 0 = disable |
0…30 |
20 |
K |