Parameters WE Parameter level / Range of valuesMax. DHW temperature* 60 °C PA4 / 5 to 90 °CHysteresis** 5 °C PA4 / 0 to 30 °CCharging temperature boost*** 10 °C PA4 / 0 to 50 °CMax. charging temperature 80 °C PA4 / 20 to 130 °C (only with VF4)Lag of storage tank charging pump 0.5 PA4 / 0 to 10.0* Parameters serve as limitation of the adjustment range for the DHW temperature to be setat the rotary switch** Deactivation value T =DHW temperature +hysteresis*** Charging temperature T =DHW temperature +charging temperature boost6.3 DHW heating in instantaneous heating systemWithout a flowmeter or flow switch, the requiredDHW temperature at sensor VF is only reg-ulated during the times-of-use of the circulation pump ZP. The flowmeter or flow switch allowthe controller to recognize exactly when DHW is being tapped. By deleting all thetime-of-uses for the circulation pump, it is possible to regulate the required DHW tempera-ture just while the DHW is being tapping.With the activated flow sensor V4, the temperature control is moved to upstream of the heatexchanger: Should the requiredDHW temperature measured at the flow sensor VF4 be toolow, theFlow temperature set point upstream of the heat exchanger is raised in steps of1 °C. When the set point reaches theMaximum charging temperature, the temperature is notraised anymore; an “Err 4” error message is generated.88 EB 5579 ENFunctions of the DHW circuitWWVFZPKWFig. 11 · Schematics of an instantaneous heating system with water flowmeter(CO4 -> F04 - 1, select: AnA)VF Flow sensorZP Circulation pumpWW Hot waterKW Cold waterWater flowmeter
