System-wide functions
The Mixing valve always active function allows the heat exchanger to maintain the charging temperature using the mixing valve. The heat exchanger charging pump remains switched on and the return flow temperature is not limited outside the
When the flow sensor VFS is active, the set point in the heat exchanger charging circuit is af- fected by the system deviation in the storage tank charging circuit when the storage tank charg- ing pump is switched on:
If the temperature measured at the flow sensor is smaller than the required charging tempera- ture, the set point in the heat exchanger charging circuit is raised by 1 °C every minute.
If the set point in the heat exchanger charging circuit reaches the value in Maximum charging temperature parameter, it is not raised any further; an Err 10 alarm is generated.
Stop storage tank charging
The controller stops charging the storage tank when the water temperature in the storage tank measured at sensor SF2 (DHW demand OFF) exceeds the set point by 0.1 °C. The primary valve (Anl 2) or the mixing valve in the DHW circuit are sent pulse signals until the heat exchanger charging temperature on the primary side at sensor VFT has fallen below the Heat exchanger charging pump deactivation limit.
The heat exchanger charging pump is switched off according to the time schedule and depend- ing on the temperature. When the flow set point of the primary heating circuit is lower than the Heat exchanger charging pump deactivation limit, the heat exchanger charging pump (TLP) is first switched off when the primary heat exchanger charging temperature at sensor VFT has dropped to the same level as the flow set point of the primary heating circuit. The heat exchanger charging pump is switched off at the latest after t = 2 x Transit time of the primary valve.
The storage tank charging pump (SLP) is switched off after t = 2 x Transit time of the primary valve or when the storage tank charging temperature in the secondary circuit at sensor VFS has fallen below the Storage tank charging pump deactivation limit.
The circulation pump is switched on and off according to a time schedule.
Functions | WE | Configuration |
Storage sensor SF1 | ON | Co4 |
Storage sensor SF2 | ON | Co4 |
Flow sensor VFS | ON | Co4 |
Circulation pump | OFF | Co4 |
Storage tank system | OFF | Co4 |
Mixing valve always active | OFF | Co4 |
EB 5179 EN 53
