How to model a combined generator for heating and DHW in Detailed HVAC of Design Builder?

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Hi at all,

does anyone know how to model a combined generator both for heating and DHW in the Detailed HVAC of Design Builder?

Because the connection between the heating generator (a gas boiler) for heating and the Water outlet (including the zones that need DHW) is not allowed...

I am forced to model two separate generators... please could someone help me!