Grundfos MAGNA3 Pumps
Spare Parts for MAGNA3 Range Pumps
Product Summary
Genuine and compatible spare parts for the Grundfos MAGNA3 variable speed circulator, used across Australia in commercial buildings for heating, chilled water, hot water recirculation (MAGNA3 N) and HVAC duties. The MAGNA3 is a wet-rotor pump with sealed internals, so service centres on the replaceable pump head, control box, sensor and seals rather than a strip-down; tick what you need and we’ll match the exact part to your nameplate (e.g. MAGNA3 40-120 F).
Spare Parts List
✓ Tick the parts you need. Grundfos MAGNA3 spares are matched to pump model, housing and production version, so your nameplate is all we need to get them right. Not sure which items? Add a photo of the nameplate and we’ll work out the part for you.
| Select | Wear / Service Item | Function & when to replace |
|---|---|---|
| Common Service Kits | ||
| Pump Head Kit | The complete replaceable pump head (stator, rotor, impeller and fitting parts) for your model. The usual fix for a seized, noisy or failed MAGNA3, leaving the pump housing in the pipework. | |
| Control Box Kit | The control box with the built-in frequency converter, display and controls. Replace if the pump shows a persistent internal or electronics fault. | |
| Sensor Kit | The integrated differential pressure and temperature sensor with its cable. Replace if the pump reports a sensor fault or the readings are wrong. | |
| O-ring & Gasket Kit | The pump head O-ring and flange or union gaskets. Renew whenever the pump head is removed or the pump is re-installed. | |
| Insulating Shell Kit | The insulating shells that wrap the pump housing (versions for heating and for chilled water). Replace if lost or damaged. | |
| Other Core Parts | ||
| Clamp Kit | The clamp and screws that hold the pump head to the housing. Replace if corroded or damaged. | |
| Connector & Cable Gland Kit | Supply and signal plugs and cable glands for the control box. Replace if damaged or lost during re-installation. | |
| CIM Communication Module | Plug-in interface for BMS communication (e.g. BACnet MS/TP, Modbus RTU, Profibus DP, LonWorks, GENIbus). Fit or replace to connect the pump to your building management system. | |
| Complete Replacement Pump | When a repair doesn’t stack up, we quote a like-for-like MAGNA3 or MAGNA3 N from the model on your nameplate. | |
How we confirm the exact part: MAGNA3 spares depend on the model, housing (cast iron or stainless N), connection and production version. Your nameplate carries all of it, in the model (e.g. MAGNA3 40-120 F), the product number and the production code. Tick the items above and add a nameplate photo, and we’ll confirm the correct part and price for your exact pump.
Models
Spare parts are available for every MAGNA3 and MAGNA3 N model in the current Grundfos Australia range. In the model (e.g. MAGNA3 40-120 F), 40 is the port size, 120 the maximum head in decimetres, F a flanged version and N the stainless steel housing for domestic hot water.
Models & Key Specifications
| Size | Models | Connection | Port-to-port | Max. pressure |
|---|---|---|---|---|
| MAGNA3 25 | 25-40, 25-60, 25-100 · N: 25-60, 25-100, 25-120 | G 1½ union | 180 mm | 10 bar |
| MAGNA3 32 | 32-100 · N: 32-60, 32-100, 32-120 | G 2 union | 180 mm | 10 bar |
| MAGNA3 32 F | 32-120 F · N: 32-120 F | DN32 flanged | 220 mm | PN 6/10 |
| MAGNA3 40 F | 40-120 F, 40-150 F, 40-180 F · N: 40-180 F | DN40 flanged | 250 mm | PN 6/10 |
| MAGNA3 50 F | 50-60 F, 50-120 F, 50-180 F | DN50 flanged | 240–280 mm | PN 6/10 |
| MAGNA3 65 F | 65-60 F, 65-120 F, 65-150 F | DN65 flanged | 340 mm | PN 6/10 |
All models: liquid temperature −10 °C to +110 °C, ambient 0 to +40 °C, max. 10 bar (PN16 versions on request), 1 × 240 V 50/60 Hz, indoor installation only. MAGNA3: cast iron housing; MAGNA3 N: stainless steel housing for domestic hot water. Composite impeller, built-in differential pressure and temperature sensor, AUTOADAPT and Grundfos GO. Also supplied as duty/standby dual hot water circulator sets (MAGNA3 N).
Troubleshooting
Pump will not start
Likely cause: no supply, a stop signal from the BMS or external input, or a seized rotor after standing idle. Action: check the supply and the display or Grundfos GO for a stop command or alarm; if the rotor is blocked by scale or debris, replace the pump head kit.
Pump shows an alarm
Likely cause: a supply fault, a blocked rotor, dry running, a sensor fault or an internal electronics fault. Action: read the alarm code on the display or with Grundfos GO; restore supply and fill and vent the system; a sensor alarm points to the sensor kit, a persistent internal fault to the control box or pump head.
Low flow or poor heating / cooling
Likely cause: wrong control mode or set point, air in the system, a closed valve or blocked strainer, or a worn or blocked impeller. Action: check the control mode and set point (AUTOADAPT suits most systems); vent the system; check valves and strainers; inspect the pump head if output stays low.
Noise from the pump
Likely cause: air in the pump, too low inlet pressure (cavitation), debris in the impeller or worn rotor bearings. Action: vent the system and raise the system pressure; check the inlet pressure suits the liquid temperature; replace the pump head kit if the noise is mechanical.
Leaking at the pump head or flanges
Likely cause: a perished pump head O-ring or flange gasket, or a loose clamp. Action: isolate and drain the pump, then fit the O-ring and gasket kit and tighten the clamp evenly.
Condensation or corrosion on the pump (chilled water)
Likely cause: missing or damaged insulating shells, or heating-type shells on a cooling duty. Action: fit the correct insulating shell kit and keep the control box clear of drips; replace a corroded clamp.
Request for Quotation
Selected Parts:
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Not sure which parts? Just send a photo of the nameplate or part below.