Grundfos ALPHA2 GO 25-60 130 Circulator Pump

The Grundfos ALPHA2 GO 25-60 130 circulator pump, reference 93074218, is a high-efficiency electronic circulator designed for water circulation in heating and air conditioning systems. It offers a maximum head of 6 meters, a nominal flow rate of 1.9 m³/h, modulating electrical power of just 3 to 37 W, G 1½" threaded connections, and a compact installation length of 130 mm.

The ALPHA2 GO combines advanced hydraulic control with direct connectivity via Bluetooth and the Grundfos GO app. It includes AUTOADAPT, proportional pressure, constant pressure, constant flow, constant curve and PWM input, as well as functions aimed at simplifying commissioning, hydraulic balancing, diagnostics and replacement of existing circulators.

Circulator pump with a maximum head of 6 meters

The Grundfos ALPHA2 GO 25-60 130 reaches a maximum head of 6 m. Its nominal operating point is set at a flow rate of 1.9 m³/h and a head of 3.26 m.

The actual operating point will depend on the pressure losses in the circuit, the required flow rate and the selected control mode.

Thanks to its electronically commutated motor and integrated frequency converter, the pump can automatically adjust its operating speed and avoid running permanently at maximum power when the installation does not require it.

AUTOADAPT to automatically adjust operation

The ALPHA2 GO incorporates the AUTOADAPT function, developed by Grundfos to automatically optimize the circulator setpoint according to the system’s actual needs.

AUTOADAPT is available in both proportional pressure and constant pressure. This means it can be used in radiator systems and underfloor heating without the need to manually select a single fixed operating point.

The function analyzes the circuit demand and progressively adapts operation with the aim of providing the required flow and pressure.

Different control modes

The Grundfos ALPHA2 GO allows the hydraulic behavior to be adapted to different types of installations through several control modes:

• Proportional pressure: adjusts differential pressure according to the demanded flow, especially useful in radiator systems with thermostatic valves.
• Constant pressure: maintains a stable differential pressure even when flow varies, a setting especially suitable for underfloor heating circuits.
• Constant flow: regulates the pump to maintain the set flow rate.
• Constant curve: allows operation following a selected fixed curve.
• AUTOADAPT: automatically optimizes the setpoint.
• PWM control: allows a compatible external controller to modulate circulator operation.

Bluetooth connectivity with Grundfos GO

The ALPHA2 GO incorporates Bluetooth to establish a direct connection with the Grundfos GO app from a compatible mobile device.

This communication allows the installer to access advanced functions without the need for additional communication interfaces.

Using Grundfos GO, tasks such as the following can be performed:

• Guided setup.
• Selection of the control mode.
• Setpoint calculation.
• AUTOADAPT configuration.
• Hydraulic balancing.
• Operating data review.
• Trend visualization.
• Event log review.
• Warning and alarm diagnostics.
• Pump software update.
• Assistance for replacing existing circulators.

Guided setup for new installations

The Grundfos GO app includes a specific guided setup function for ALPHA2 GO.

During commissioning, the app requests information about the installation and helps identify the appropriate control mode and setpoint.

When AUTOADAPT is suitable, the app may recommend this mode so the pump can automatically optimize its operation. When a different configuration is needed, Grundfos GO helps calculate the required setpoint.

Suitable for radiators and underfloor heating

The different control modes allow the ALPHA2 GO 25-60 130 to be used in numerous heating and air conditioning installations.

Typical applications include:

• Radiator heating systems.
• Underfloor heating.
• Closed heating circuits.
• Hydronic air conditioning systems.
• Boiler-connected circuits.
• Systems compatible with heat pumps.
• Replacement of standalone circulators.
• Replacement of certain compatible integrated UPM3 and UPM4 pumps.

Specially designed for circulator replacement

Grundfos has developed the ALPHA GO range with special attention to the replacement of existing circulator pumps.

The replacement function integrated in Grundfos GO allows you to search for an old pump and check which ALPHA GO model is suitable as a replacement.

In the case of ALPHA2 GO, the direct connection with the app allows the new circulator to be configured to replicate certain operating curves of compatible pumps, a particularly useful function when replacing integrated circulators.

Replacement of UPM3 and UPM4 pumps

Grundfos specifically indicates that ALPHA2 GO is prepared to facilitate the replacement of different integrated UPM3 and UPM4 pumps, as well as standalone circulators.

The app helps identify the reference being replaced and transfer a suitable operating configuration to the new pump.

Air detection and venting

The ALPHA2 GO features an air detection function that can be activated via Grundfos GO.

When the pump detects air around the impeller, it can temporarily operate in pulses to help move it toward the nearest venting device in the installation.

This function facilitates commissioning and diagnostics, although it does not replace proper system venting.

Dry-run protection

The circulator includes dry-run protection.

If the pump is detected to be operating without the necessary amount of liquid, the unit can stop and generate an alarm to prevent it from continuing to run under unsuitable conditions.

In ALPHA2 GO, this type of event can be logged and reviewed via Grundfos GO to facilitate diagnostics.

Robust startup against blockages

The Robust Startup function is designed to help the pump start even when the rotor encounters resistance due to dirt, magnetite or deposits.

In the event of a blockage, the motor makes repeated start attempts using high torque to try to restore movement.

This feature is especially useful after long periods of inactivity in a heating installation.

Ceramic shaft and bearings

The ALPHA2 GO uses a ceramic shaft and bearings, developed to offer reduced wear during operation.

This construction helps maintain stable internal clearances and helps limit the appearance of mechanical noise associated with wear.

Hydraulic balancing via Grundfos GO

The connection with Grundfos GO allows hydraulic balancing of the installation to be carried out.

A properly balanced system distributes the required flow between the different emitters and circuits, avoiding areas with excess or insufficient circulation.

This function is especially useful in installations with multiple radiators or multiple underfloor heating circuits.

Event log and trend data

Grundfos GO allows historical information related to the operation of the ALPHA2 GO to be reviewed.

Parameters that can be analyzed include trends in:

• Flow rate.
• Head or delivered pressure.
• Energy consumption.
• Estimated fluid temperature.
• Operating cycle duration.

The app also maintains an event log that makes it easier to identify warnings, alarms and possible operating issues.

PWM input for external control

The ALPHA2 GO incorporates a PWM input that allows the pump speed to be precisely controlled from a compatible external controller.

This makes integration easier in systems where the heat generator itself, such as a boiler or compatible heat pump, needs to directly manage the circulator.

High energy efficiency with EEI 0.18

Reference 93074218 has an energy efficiency index EEI of 0.18.

The electrical power absorbed is regulated between just:

• Minimum P1 power: 3 W.
• Maximum P1 power: 37 W.

This modulation allows consumption to be adapted to the needs of the circuit and represents a significant difference compared with older fixed-speed circulators.

Single-phase 220-240 V power supply

The Grundfos ALPHA2 GO 25-60 130 operates with a single-phase 220-240 V, 50/60 Hz power supply.

Current consumption ranges between:

• Minimum current: 0.04 A.
• Maximum current: 0.40 A.

The pump incorporates electronic thermal protection and has insulation class F.

Quick-install electrical connector

Grundfos equips the ALPHA2 GO with an installation connector designed for tool-free electrical connection.

This system makes both new installations and replacement of an existing circulator easier.

Compact installation length of 130 mm

The 130 designation of the model corresponds to a 130 mm connection distance.

This format is especially useful in installations where available space is limited or when replacing an existing pump with the same construction length is required.

Before carrying out a replacement, both the 130 mm length and the hydraulic connection diameter should be checked.

G 1½" hydraulic connections

Reference 93074218 includes G 1½" threaded connections according to ISO 228-1.

The nominal pressure of the connections is PN 10.

The combination of G 1½" connection and 130 mm length distinguishes this version from other ALPHA2 GO 25-60 models that use a 180 mm installation distance.

Maximum operating pressure of 10 bar

The pump supports a maximum operating pressure of 10 bar.

The hydraulic circuit and its safety components must be sized to keep pressure within the limits permitted by the circulator and the other components of the installation.

Liquid temperature from 2 to 110 °C

Grundfos specifies for reference 93074218 a pumped liquid temperature range of 2 to 110 °C.

The permitted ambient temperature during operation is between 0 and 55 °C.

This wide range allows it to be used in different closed heating and air conditioning circuits, provided the fluid and the rest of the components are compatible.

Cast iron pump housing

The hydraulic housing is made of EN-GJL-150 cast iron.

The impeller uses a reinforced composite material made of PES with 30% glass fiber and PESU-GF20%.

This version is intended mainly for closed heating and air conditioning circuits.

IP44 protection

The Grundfos ALPHA2 GO 25-60 130 has an IP44 protection rating.

Installation must comply with the mounting positions, environmental conditions and electrical requirements specified by the manufacturer.

Technical features of Grundfos 93074218

• Brand: Grundfos.
• Range: ALPHA2 GO.
• Model: ALPHA2 GO 25-60 130.
• Reference: 93074218.
• Type: high-efficiency electronic circulator pump.
• Application: heating and air conditioning.
• Fluid specified in datasheet: water.
• Nominal flow rate: 1.9 m³/h.
• Nominal head: 3.26 m.
• Maximum head: 6 m.
• Installation length: 130 mm.
• Connection type: G threaded.
• Connection size: G 1½".
• Connection standard: ISO 228-1.
• Nominal pressure: PN 10.
• Maximum operating pressure: 10 bar.
• Liquid temperature: 2-110 °C.
• Ambient temperature: 0-55 °C.
• Power supply: 1 x 220-240 V.
• Frequency: 50/60 Hz.
• Minimum absorbed power: 3 W.
• Maximum absorbed power: 37 W.
• Minimum current: 0.04 A.
• Maximum current: 0.40 A.
• Energy efficiency index EEI: 0.18.
• Frequency converter: integrated.
• Thermal protection: electronic.
• Protection rating: IP44.
• Insulation class: F.
• Housing material: EN-GJL-150 cast iron.
• Impeller material: composite PES 30% GF + PESU-GF20%.
• Proportional pressure: yes.
• Constant pressure: yes.
• Constant flow: yes.
• Constant curve: yes.
• AUTOADAPT: yes.
• PWM input: yes.
• Bluetooth: integrated.
• Compatible with Grundfos GO: yes.
• Guided setup: yes.
• Air detection and venting: yes.
• Dry-run protection: yes.
• Robust startup: yes.
• Hydraulic balancing: yes, via Grundfos GO.
• Event log and trends: yes.
• Head orientation: 9H.
• Approvals: CE and VDE.
• Net weight: 1.76 kg.
• Gross weight: 1.98 kg.
• EAN: 5715467404456.

Compact and intelligent circulator for heating

The Grundfos ALPHA2 GO 25-60 130 combines a maximum head of 6 meters and G 1½" connections with a compact length of just 130 mm, making it easy to integrate into installations where available space is limited.

Its 3 to 37 W consumption, EEI of 0.18, AUTOADAPT and different control modes allow operation to be adapted to radiator systems, underfloor heating and other closed heating and air conditioning circuits.

Direct connection with Grundfos GO adds guided setup, hydraulic balancing, air detection, diagnostics, historical logging and specific tools for circulator replacement, making it a particularly complete solution for new installations and upgrades.