Question: On a Magna 3, do I install a CIM card in the master pump or both?

Answer: It depends on which model. If it is a single head Magna 3, both require CIM cards to communicate back to the BMS. For the dual head Magna 3D models, the older (pre-2018) series needs a card in each head. For the latest dual head “D” series, only in the master head.

See below for CIM/CIU and Multi-pump applications for more details.

For additional information, please contact your local Grundfos rep agency.