System-wide functions
7 System-wide functions
7.1Automatic summer time/winter time changeover
The clock is automatically adjusted on the last Sunday in March at 2.00h and on the last Sunday in October at 3.00h.
Function | WE | Configuration |
Summer time/winter time changeover | ON | FB5 = ON |
7.2Frost protection
When outdoor temperatures below 3 °C occur, the heating circulation pumps UP1 and UP2 are switched on. The controllers regulates the temperature to a flow temperature set point of 20 °C. The circulation pump for the DHW circuit is likewise switched on. Outside the DHW heating
Note!
The frost protection function is not activated when manual mode is selected at the mode switch.
7.3Forced operation of the pumps
When the heating circuit pumps have not been activated for 24 hours, forced operation of the pumps is started between 00.00h and 00.01h. This is done to avoid that the pumps get stuck when they are not operated for a longer period of time. The forced operation of the storage tank or heat exchanger charging pump is operated between 00.01h and 00.02h.
7.4Return flow temperature limitation
The temperature difference between the flow and return flow indicates how well the energy is used: the greater the difference, the higher the efficiency. A return flow sensor is sufficient to evaluate the temperature difference when the flow temperatures are preset. The return flow tem- perature can be limited either to a value depending on the outdoor temperature (variable) or to a fixed set point. When the temperature measured at return flow sensor RüF exceeds the limit value, the set point of the flow temperature (flow temperature of the heating system, charging temperature) is reduced. As a result, the primary flow rate is reduced and the return flow tem- perature falls. The Limiting factor determines how strongly the controller responds when the limit values are exceeded in either direction.
EB 5476 EN 57
