Grundfos UPM3 FLEX AS 25-70 130 AZA PWM Circulator Pump - 93008970

Description

The Grundfos UPM3 FLEX AS 25-70 130 AZA (part no. 93008970) is a high-efficiency circulator pump built to run with or without an external PWM control signal, making it one of the most widely specified pumps for underfloor heating manifolds — from single-port setups up to 12-port manifold systems. Its compact 130 mm port-to-port body suits tight manifold cabinets and boiler compartments alike.

7 m

Max Head

110 °C

Max Flow Temp

2–52 W

Power Input

EEI ≤ 0.20

Energy Index

1½" BSP

Connection

130 mm

Port-to-Port

Please Note

This pump can run with or without a PWM signal. Without an external PWM controller connected, it defaults to running at a fixed speed setting rather than adapting automatically like the UPM3 AUTO 25-70 130 (part no. 59C93602). For multi-zone manifold systems with only an on/off thermostat and no PWM wiring centre, the AUTO variant will generally give better part-load efficiency — see the comparison FAQ below.

Why Choose the UPM3 FLEX AS

Dual-Mode PWM Operation

Operates as a digital low-voltage PWM-controlled circulator when wired to a compatible manifold controller or wiring centre, while remaining fully functional as a standalone fixed-speed pump when no PWM signal is present — one product covers both scenarios.

Built for Manifold Retrofits

Its control flexibility makes it the go-to choice for underfloor heating manifold upgrades, allowing installers to add PWM zone control later without swapping the pump.

Ceramic Bearing Shaft

Fitted with the same ceramic bearing shaft used across the UPM3 range, resisting limescale build-up in hard-water areas for a longer maintenance-free service life.

Double De-Blocking System

Combines electronic de-blocking with a manual front-accessible de-blocking screw, so a rotor seized after seasonal shutdown can be freed without dismounting the pump head.

High Ambient Temperature Tolerance

Designed to operate reliably in enclosed cabinets and appliance housings with ambient temperatures up to 70 °C, common in manifold cupboards and boiler compartments.

Space-Saving Design

A low space requirement and front-accessible user interface, connectors, and de-blocking screw simplify installation and servicing in confined manifold cabinets.

Technical Specification

Electrical Data
Rated voltage	1 × 230 V, 50 Hz
Power input (P1)	2 – 52 W
Maximum current consumption	0.04 – 0.52 A
Enclosure class	IP44
Motor protection	Not required (self-protecting)
Liquid Data
Pumped liquid	Water, clean and thin, non-aggressive
Liquid temperature range	2 – 110 °C
Mechanical / Installation
Maximum head	7 m
Port-to-port length	130 mm
Connection thread	1½" BSP (G 2")
Maximum operating pressure	10 bar
Approvals
Certifications	CE, VDE
Warranty	2 year manufacturer warranty

Frequently Asked Questions

What's the difference between the UPM3 FLEX AS and the UPM3 AUTO 25-70 130?

The FLEX AS (93008970) is built to accept an external PWM signal from a manifold controller or wiring centre, letting zone demand vary pump speed directly. The AUTO (59C93602) has no PWM input and instead regulates itself automatically via AUTOADAPT. If your manifold has, or will have, PWM zone control wiring, choose the FLEX AS. If you want a standalone pump that self-optimises with no external controller, choose the AUTO.

Will this pump work if I don't have a PWM controller?

Yes. Without a PWM signal connected, the UPM3 FLEX AS runs at a fixed speed setting rather than adapting automatically. It will still circulate the system correctly, but for multi-zone manifolds without PWM wiring, the AUTO variant typically gives better efficiency across partial loads.

How many manifold ports can this pump support?

The UPM3 FLEX AS 25-70 130 AZA is suitable for underfloor heating manifolds ranging from single-port setups up to 12-port manifold systems, depending on system design and pressure requirements.

What connection size and port-to-port length does it use?

It uses a 1½" BSP (G 2") threaded connection with a 130 mm port-to-port length, matching standard UK manifold and boiler pump fittings.

Does the pump need external motor protection?

No. The permanent-magnet ECM motor is self-protecting and needs no external motor protection or overload relay beyond a standard 230 V single-phase supply.

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