Grundfos Type Key Decoder — CR, CM, NB, MAGNA3 and UPS References Explained
Standards explainer compiled by cBallast. 3-page PDF; the full content is on this page.
Brand
Grundfos
Subject
Centrifugal pumps
Document type
Standards explainer
Reference
2026 edition
Issued
2026-10-18
Pages
3
Format
Web page and PDF
How to read a Grundfos nameplate: CR/CRI/CRN flow-and-stage logic, CM horizontal multistage, NB end-suction sizes, MAGNA3 and UPS circulator codes, and the version-letter block (pump version, connection, materials, elastomer, shaft seal) that decides whether two otherwise identical references interchange.
The two numbers everyone reads first
Family
Format
Worked example from stock
CR / CRI / CRN vertical multistage
CR [nominal flow m³/h] - [number of stages]
CR10-5: 10 m³/h frame, 5 stages — I = stainless wetted parts, N = all-stainless
After the size, Grundfos appends a version block — on the stocked CR10-5 it reads A-A-A-E-HQQE, on the CM5-3 A-R-A-E-AQQE. The groups cover pump version, pipe-connection standard, material execution and the elastomer, and the final four letters are the shaft seal code, decoded letter by letter in the companion seal guide. Two CR10-5s with different blocks can differ in flange standard, O-ring compound and seal faces — all three bite during installation or CIP. Quote the entire string from the nameplate, never the bare size.
Service logic per family
CR: wear parts ship as complete overhaul kits per frame — KIT-CR1 and upward — covered in depth in the CR overhaul-kit guide; the shaft seal is a separate cartridge ordered by code and shaft size.
NB: kits per size (KIT-NB32, KIT-NB50); impeller diameter in the type key tells you the hydraulics without the curve book.
Circulators replace as complete units; match DN, head class, port-to-port length and voltage — the figures are all in the reference.
Around 370 Grundfos line items are stocked — pumps, kits, seals — browsable at the brand page. For duty-point questions behind the type key (does a CR10-5 actually fit the system?), the pump-curve guide walks the method.
Frequently asked questions
What does CR10-5 mean on a Grundfos pump?
A vertical multistage in the 10 m³/h nominal-flow frame with 5 impeller stages. Head scales with stage count — the same frame runs from a handful of stages to dozens — and the letters after it carry materials, connection and seal.
Is a CRI pump interchangeable with a CR?
Hydraulically they share the frame logic; the difference is material execution — CRI runs stainless wetted parts, CRN all-stainless, against the CR's cast-iron/stainless mix. Aggressive or potable media decide the letter, not the duty point.
How do I read MAGNA3 40-100 F?
DN40 ports, 10 m maximum head, flanged (F) — and the catalogue row states the port-to-port length (220 mm here), which must match the pipework cut-out on a swap.
What does the E mean in CME or CRE?
An integrated frequency-converter motor — the pump self-regulates to a setpoint instead of running fixed speed. The hydraulic type key reads the same; control wiring and settings come on top.
Can I order a Grundfos pump from the nameplate alone?
Yes — the full type key plus the product number on the plate pins the exact build. With both quoted, a 24-hour quotation confirms the current equivalent (Grundfos periodically supersedes product numbers while keeping the type key).