Question: What do the Magna model part numbers refer to? I cant make any sense of them.

Answer: The model numbers (or material numbers) as Grundfos refers to represent the inlet/outlet diameter and the head ability in metric. For example, the Magna 3 65-120 has a 50mm (1.96″) diameter and the head is 120 meters (36′ TDH).

To simplify figuring this out, shown below is a conversion chart so you don’t have to run the conversions:

For additional information, please contact your local Grundfos wholesaler.