Grundfos CHI 12-25 A-W-G-BQQV 415V Stainless Steel Horizontal Multistage Pump 4FZ20087 #5010

This listing is for a Grundfos CHI 12-25 A-W-G-BQQV horizontal multistage centrifugal pump, manufacturer product number 4FZ20087.

The pump features 316-grade stainless-steel hydraulic construction, 1½-inch threaded connections, a three-phase 400V / 415V motor and a BQQV mechanical shaft seal with FKM (Viton) elastomers.

Designed for industrial water transfer, pressure boosting and clean-liquid applications, this CHI 12-25 has a rated hydraulic duty of 10 m³/h at 42 metres head, making it suitable for systems requiring relatively high flow rates combined with a substantial pressure increase.

The Grundfos CHI range has been discontinued. This pump may therefore be particularly useful as a replacement for an existing CHI installation where retaining the original pump configuration could avoid extensive pipework modifications.

Condition: As-new surplus condition. Unused equipment may have minor cosmetic marks from storage and handling.

Guarantee: 2 years.

Technical Specifications

General Information

• Manufacturer: Grundfos
• Product range: CHI
• Model: CHI 12-25
• Full designation: CHI 12-25 A-W-G-BQQV
• Product number: 4FZ20087
• EAN: 5700397474198
• Stock reference: #5010
• Pump type: Horizontal multistage centrifugal pump
• Construction: Close-coupled, horizontal end-suction design
• Operating speed: Fixed-speed
• Priming arrangement: Non-self-priming
• Current manufacturer status: Discontinued

Hydraulic Performance

• Rated flow: 10 m³/h
• Rated flow in litres: 10,000 litres/hour
• Rated head: 42 metres
• Maximum operating pressure: 10 bar
• Nominal hydraulic flow family: CHI 12
• Performance frequency: 50 Hz
• Performance curve reference: Grundfos CHI 12-25

Important: The rated flow and head describe a particular operating point, not two independent maximum values. Actual performance depends on the system resistance, suction conditions, liquid properties and operating point on the manufacturer's pump curve.

Pipe Connections and Dimensions

• Suction connection: Rp 1½
• Discharge connection: Rp 1½
• Connection type: Threaded
• Suction arrangement: Axial
• Discharge arrangement: Radial
• Overall length: Approximately 500 mm
• Motor diameter dimension: Approximately 178 mm
• Approximate height: 230 mm
• Suction centreline height: 120 mm
• Net weight: Approximately 23.9 kg

Dimensions are based on the manufacturer's CHI 12-25 technical documentation. Mounting arrangements should be checked against the existing installation before ordering.

Electrical Specifications

• Motor output power (P2): 2.27 kW
• Electrical input power (P1): Approximately 2.80 kW
• Power supply: Three-phase
• Rated voltage: 3 × 220–240V Δ / 380–415V Y
• UK nominal supply: 400V / 415V three-phase
• Frequency: 50 Hz
• Rated current: Approximately 9.0A delta / 5.2A star
• Rated motor speed: Approximately 2890 rpm
• Motor enclosure: IP55
• Insulation class: F
• Integrated speed control: None
• Built-in motor protection: None

The motor requires suitable external electrical protection and controls. The electrical supply, terminal connections, overload settings and direction of rotation must be checked during installation.

Materials and Mechanical Seal

• Pump housing: Stainless steel
• Housing material grade: EN 1.4401 / AISI 316
• Impellers: Stainless steel
• Impeller material grade: EN 1.4401 / AISI 316
• Shaft seal designation: BQQV
• Mechanical seal type: Rubber bellows mechanical shaft seal
• Primary seal faces: Silicon carbide / silicon carbide
• Secondary elastomers: FKM (Viton)
• Pump construction: Corrosion-resistant stainless-steel hydraulic assembly

The combination of stainless-steel construction and a silicon carbide mechanical seal makes this pump suitable for a variety of clean-water and compatible industrial liquid duties.

However, material compatibility must be checked for the particular liquid being pumped.

What Is the Grundfos CHI 12-25 Used For?

The CHI range was developed for applications requiring the pressure capabilities of a multistage pump within a relatively compact horizontal design.

Unlike a basic single-stage transfer pump, the multistage hydraulic arrangement allows a greater pressure increase without requiring a large or particularly high-speed motor.

Common applications include:

• Commercial pressure boosting: Increasing pressure in water distribution and supply systems.
• Industrial water transfer: Transferring clean water between tanks, vessels or process equipment.
• Water treatment: Supplying filtration systems and compatible treatment processes.
• Washing and cleaning equipment: Supplying pressurised water to industrial washing machinery.
• Cooling and temperature-control systems: Circulating compatible clean liquids through industrial cooling circuits.
• Irrigation: Providing flow and pressure for appropriately sized irrigation installations.
• Industrial process equipment: Supplying machinery requiring a controlled flow of clean liquid.
• Replacement installations: Replacing an existing Grundfos CHI 12-25 where the original hydraulic and mechanical specifications are required.

The pump is designed for clean liquids. It is not suitable for sewage, wastewater containing solids, sludge or heavily contaminated liquids.

An Important Consideration When Replacing an Existing CHI Pump

The Grundfos CHI series is an older pump range that is no longer manufactured.

Although modern horizontal multistage pumps can provide similar hydraulic performance, they do not necessarily share the same dimensions, connection positions or motor arrangements.

For an existing CHI installation, this distinction can be important.

A modern alternative may require alterations to suction pipework, discharge pipework, mounting arrangements or electrical controls.

Where an existing CHI 12-25 has failed, sourcing the correct original pump can sometimes be the more straightforward solution.

Before purchasing as a replacement, compare:

1. The complete pump designation and product number.
2. Suction and discharge connection sizes.
3. Electrical supply and motor rating.
4. Required flow and head.
5. Mounting dimensions and connection centreline heights.
6. Mechanical shaft seal materials.
7. The intended pumped liquid and operating temperature.

Please contact us if you require assistance confirming compatibility with your existing installation.

Understanding the Grundfos CHI 12-25 A-W-G-BQQV Designation

The full model designation contains important information about the pump's construction.

CHI

Identifies the Grundfos CHI stainless-steel horizontal multistage pump family.

12

Identifies the nominal hydraulic flow family within the CHI range.

25

Identifies the hydraulic configuration within the CHI 12 range. It should not be interpreted as a maximum head of 25 metres.

A

Standard pump version.

W

Threaded pipe connection arrangement.

G

Stainless-steel material configuration, using EN 1.4401 / AISI 316 or equivalent specified materials.

BQQV

Mechanical shaft seal designation incorporating silicon carbide seal faces and FKM elastomers.

The full designation is important because pumps within the same CHI hydraulic family may have different motors, mechanical seals, voltage configurations or product numbers.

BQQV Mechanical Shaft Seal – Why Does It Matter?

This pump uses a Grundfos BQQV mechanical shaft seal.

The seal incorporates silicon carbide running faces together with FKM secondary elastomers.

Silicon carbide is a hard, wear-resistant material commonly selected for mechanical seal faces in centrifugal pumps.

The FKM elastomers are an important consideration because they offer different chemical compatibility characteristics from EPDM, which is commonly used in other water-pump configurations.

Depending on the liquid and operating conditions, FKM can be advantageous for certain industrial fluids and hydrocarbon-related applications.

However, this does not mean that the pump is automatically suitable for all chemicals, oils, solvents or fuels.

Liquid compatibility must be assessed against:

• The exact liquid or chemical composition.
• Operating temperature.
• Viscosity and density.
• Stainless-steel compatibility.
• Mechanical seal face suitability.
• FKM elastomer compatibility.
• Operating pressure and suction conditions.

For water-based systems, the manufacturer’s liquid-temperature guidance must also be followed. The permitted temperature range varies according to the liquid and sealing arrangement.

For applications involving unusual chemicals or temperatures, we recommend checking the complete duty before purchasing.

Frequently Asked Questions

Is the Grundfos CHI 12-25 still manufactured?

No. The CHI range has been discontinued.

Grundfos identifies product number 4FZ20087 as no longer in production and does not currently identify a direct replacement in its online catalogue.

Alternative pumps may be available, although compatibility must be assessed individually.

Is this a direct replacement for any Grundfos CHI 12-25?

Not necessarily.

There are several versions of the CHI 12-25 with different manufacturer product numbers, motor configurations and shaft seals.

This particular pump is CHI 12-25 A-W-G-BQQV, product number 4FZ20087.

If your existing pump carries a different product number, we recommend checking the full specification before ordering.

Is this a 230V or 415V pump?

This listing is for a three-phase 400V / 415V class pump.

The motor has a dual-voltage star/delta configuration, but it is not a standard single-phase 230V pump.

A suitable three-phase supply and correctly configured motor controls are required.

How much pressure does the CHI 12-25 produce?

The manufacturer's rated hydraulic duty for this product is 10 m³/h at 42 metres head.

This is the pressure increase produced at the stated rated flow under the manufacturer's reference conditions.

Actual pressure and flow depend on the connected system and pump operating point.

The rated head must not be confused with the maximum permissible system operating pressure of 10 bar.

Is this pump self-priming?

No.

The Grundfos CHI 12-25 is a normal-suction centrifugal pump.

It must be properly primed before starting and must not be operated dry.

For installations where the pump is positioned above the liquid level, the suction arrangement and available NPSH require particular attention.

Can this be used for pressure boosting?

Yes.

The CHI 12-25 can be used for pressure boosting when correctly sized for the application.

However, this listing is for the pump itself, not a complete automatic booster set.

Pressure switches, pressure transducers, expansion vessels, motor controls and other accessories may be required depending on the installation.

Can I use this pump with a frequency inverter?

This is a conventional fixed-speed CHI pump without an integrated frequency converter.

External inverter operation may be possible where the motor and operating conditions permit, but the motor's suitability, cooling requirements and operating frequency limits must be checked.

Can the CHI 12-25 pump hot water?

The CHI range was manufactured for a variety of water and industrial liquid applications, including temperature-control duties.

However, maximum permissible liquid temperature depends on the shaft seal elastomers, liquid properties and operating pressure.

This version uses FKM elastomers rather than the EPDM configuration found on some other CHI pumps.

The relevant Grundfos temperature limits should be checked before use in hot-water applications.

Is this suitable for glycol?

Potentially, subject to the type and concentration of glycol, operating temperature and compatibility of the mechanical seal.

Water-glycol mixtures have different viscosity and hydraulic characteristics from clean water.

Pump performance, motor load and suction requirements may therefore differ from standard published water curves.

Is this suitable for drinking water?

Stainless-steel construction alone does not establish suitability for potable water.

Any drinking-water application should be assessed against the product's applicable approvals, seal materials, installation requirements and current regulations.

We would not recommend assuming potable-water approval without checking the documentation for this particular version.

Can I replace this pump with a Grundfos CM or CME?

A modern Grundfos CM or CME pump may offer a suitable hydraulic alternative in some applications.

However, it should not be assumed to be a direct physical replacement.

The hydraulic duty, connection sizes, materials, motor supply, installation dimensions and control requirements must all be checked.

The CME range also incorporates electronic speed control, whereas this CHI pump is a conventional fixed-speed design.

What should I check before installing the pump?

The pump should be installed in accordance with the manufacturer's installation instructions.

Particular attention should be given to:

• Correct suction conditions and priming.
• Adequate motor ventilation.
• Suitable electrical overload protection.
• Correct three-phase direction of rotation.
• Proper pipework support.
• Air removal from the pump and connected system.
• The operating point relative to the manufacturer's performance curve.
• Compatibility between the pumped liquid and mechanical seal materials.

The pump should never be run dry.

Manufacturer Information

The official Grundfos Product Center identifies this pump as:

Grundfos CHI 12-25 A-W-G-BQQV

Product number: 4FZ20087

The manufacturer’s CHI technical literature contains additional information, including performance curves, installation dimensions, motor ratings, construction materials and liquid compatibility guidance.

For customers replacing an existing pump, we recommend checking the original nameplate and comparing the required duty against the manufacturer's performance information.

Need Help Confirming Suitability?

We specialise in supplying commercial and industrial pumps, including discontinued Grundfos models.

If you are replacing an existing CHI pump or need help checking the hydraulic performance, please contact us with the original model number and details of your installation.

Telephone: 01803 220416

We can assist with identifying the correct pump and checking potential replacement options.

About Our Stock

Stock reference: #5010

The Pump Dealer specialises in supplying new, unused and surplus commercial pump equipment, including discontinued and difficult-to-source models.

This pump is offered in as-new surplus condition. Unused surplus equipment may show minor cosmetic marks resulting from storage or handling.

Guarantee: 2 years.

Please verify the full pump designation, product number, electrical supply, connection sizes and hydraulic suitability before purchasing.

All prices are subject to VAT at the applicable rate.