Logano plus SB315, SB615, SB745 - Buderus

8 System examplesArea of application• Logano plus SB315, SB615 and SB745 floorstanding condensing boilers• Logamatic 4321/4322 boiler and heating circuitcontrol unitFunction descriptionThe boiler sequence can be switched on the basis of loadand time. The lead boiler starts when the actualtemperature captured by the strategy sensor in the lowloss header or common flow falls below the set flowtemperature. The lag boiler is hydraulically shut off via thecheck valve in the flow. When the heat demand increases,the lag boiler is automatically started. When the load falls,the switching processes run in reverse order.Special design information• If a boiler sequence reversal is required, this can be setmanually or automatically.• In conjunction with hydraulic balancing, the boilercircuit pump PK is advisable if there are severaldistributor stations, or if these are far apart. A low lossheader or low pressure distributor with bypass andcheck valve can be used for hydraulic balancing.• The low loss header is also suitable for de-sludging.• With the Flow-Control function, it is possible to reducethe running costs through increased utilisation of thecondensing effect as well as lowering the powerconsumption.(Speed control of the modulating boiler circuit pumpsvia 0 -10 V to prevent mixing in the low loss headerfrom the boiler flow to the return: pump with 0 -10 Vinterface required)You can check the system hydraulics (5-5-1-2-2) in the Buderus hydraulics database atwww.buderus.de/hydraulikdatenbank.70Technical guide Floor standing gas/oil condensing boilers Logano plus SB315, SB615, SB745 – 6 720 802 589 (2012/01)