Grundfos UPM3 Settings
Proportional pressure: Radiators with TRVs
const pressure: Underfloor heating
const curve( Fixed speed settings): Radiators with no TRVs and autobypass.
If there is an external pump being used set to proportional pressure maximum curve and leave underfloor heating manifold on constant pressure curves, autoadapt ok. Otherwise speak to UFH manufacturer for recommending setting.