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Viessmann and Vitocell Control

In the process of laying out a new job for a customer reno of their home. Due to space the idea was floated to use an indirect for DHW. We use Viessmann for our modcon boilers. We have yet to use an indirect on a Viessmann B1HE, so I haven't had the need to set one up for it. Aside from using the suppled tank sensor, it appears that the boiler switches to to DHW priority as required and uses its internal pump to supply water to the tank from the primary side of the system? It's unclear if the DHW re circ pump for the tank can be controlled by the boiler controls or is a separate aqua stat needed for re circ pump. Was scratching my head looking at the diagrams and reading the manual yesterday.