Grundfos ALPHA2 15-40 130

The ALPHA2 15-40 130 is a premium, ultra-compact low-head circulator pump from Grundfos’ award-winning ALPHA2 series – the world’s most advanced residential circulator. Delivering 4 meters (40 kPa) of head pressure with compact 15mm (½”) connections in the industry-standard 130mm flange-to-flange format, this pump is specifically designed for low-resistance compact systems where space is at a premium and gentle circulation is required. Unlike larger pumps, the 15-series is engineered for small combi boilers, individual fan coil units, single underfloor heating loops, and domestic hot water recirculation in tight spaces. Featuring Grundfos’ intelligent AUTOADAPT technology, the pump automatically learns your system’s characteristics and continuously optimizes performance – no manual speed selection, no guesswork, no wasted energy.

Key Benefits

• Low Head (4m / 40 kPa): Gentle circulation perfect for small combi boilers, fan coils, and underfloor loops – prevents noise and system stress.

• Ultra-Compact 15mm (½”) Connections: Ideal for small combi boilers, fan coil units, and tight mechanical rooms where larger pumps won’t fit.

• Industry-Standard 130mm Flange: Direct drop-in replacement for older 15-series low-head circulators – no pipe modification required.

• AUTOADAPT Technology: The pump automatically learns your system and continuously adjusts performance for peak efficiency – set it and forget it.

• Massive Energy Savings: Consumes as little as 5 Watts – up to 85% less energy than older UPS 15-40 or UNO pumps. That’s less than a night light!

• Alarm Relay Output: Remote fault signaling for integration with home automation systems.

Performance Details
The ALPHA2 15-40 130 delivers a maximum head of 4 meters (40 kPa) and a maximum flow rate of 1.8 m³/h. The pump features multiple operating modes:

Additional features:

• Night setback mode – Automatic speed reduction for DHW recirculation during low-demand hours (2am-5am default)

• LED user interface – Color-coded status and fault indication for easy troubleshooting

• Alarm relay output – Remote fault signaling (volt-free contact)

Why Choose the 15-40 (4m Low Head)?
The 15-40 is the smallest, most energy-efficient pump in the ALPHA2 15-series. Choose it when:

The Problem with Oversized Pumps on Small Systems:
Many small systems have pumps that are too powerful (6m or 8m). This causes:

• ❌ Uncomfortable water noise (rushing/hissing sounds in small pipes)

• ❌ Increased energy consumption (higher bills – paying for pressure you don’t need)

• ❌ Premature boiler heat exchanger wear

• ❌ Short-cycling and inefficient operation

If you have a small combi boiler in a studio or 1-bedroom apartment, you likely only need a 4m pump.

ALPHA2 15-40 vs ALPHA1 15-40 130: Which to Choose?

Choose ALPHA2 if: You want maximum energy savings (pays for itself) and automatic performance optimization for your small system.

AUTOADAPT Technology Explained
Unlike simple 3-speed pumps where you guess the right setting, AUTOADAPT continuously monitors your heating system’s demand:

1. Learning phase (first few days): Pump maps your system’s pressure/flow characteristics

2. Optimization phase: Automatically selects the most efficient pressure curve

3. Continuous adjustment: Responds to changing conditions (zone valves closing, TRVs adjusting, etc.)

Benefits of AUTOADAPT for Small Systems:

• ✅ No manual speed selection – The pump finds the optimal setting for your small combi or fan coil

• ✅ Maximum energy savings – Never wastes energy over-pumping (as low as 5W!)

• ✅ Silent operation – No excess pressure causing noise in small pipes

• ✅ Longer component life – Boiler heat exchanger and valves see less stress

ALPHA2 15-40 vs 15-60 vs 15-80:

Choose 15-40 if: You have a small system with low resistance and want the absolute lowest energy consumption (as low as 5W).

Applications & Usage

• Small combi boilers – Studio and 1-bedroom apartments

• Individual fan coil units (FCUs) – Single room heating/cooling

• Single underfloor heating loops – Small bathroom or kitchen zones

• Domestic hot water recirculation (short loops)

• Tight mechanical rooms / boiler cupboards – Smallest footprint available

• Small apartment heating systems (1 story, compact)

• Replacement for older UPS 15-40 130 pumps – Direct drop-in upgrade

Durability & Reliability
Engineered for quiet, efficient, continuous operation:

• Stainless steel rotor can (AISI 304) – corrosion-resistant

• Ceramic bearings & graphite thrust bearing – self-lubricating, wear-resistant (50,000+ hours typical life)

• Dry-running protection – automatic shutdown if water supply is interrupted

• Automatic de-airing function – self-venting during startup, prevents air lock damage

• Cast iron housing – durable and compact

• IPX4D splash-proof rating – safe for mechanical rooms and boiler cupboards

• Alarm relay output – remote fault signaling for home automation integration

Customer Value
For NPF Store customers with small combi boilers, fan coil units, or tight spaces requiring gentle circulation, the ALPHA2 15-40 130 is the ultimate solution. It directly replaces older UPS 15-40 pumps and other 15mm low-head circulators without pipe modification. The combination of 4m low head (gentle circulation), AUTOADAPT technology (automatic optimization), and ultra-low power consumption (as low as 5W – less than a night light) ensures your small system operates at absolute peak efficiency. With an annual energy cost as low as $7-10, this pump typically pays for itself within 12-18 months. For contractors, the drop-in 130mm flange and alarm relay output make it the professional choice for compact system upgrades.

4. Key Features

• ✅ 4m Head (40 kPa) – Gentle circulation for small combis, fan coils, and underfloor loops

• ✅ 15mm (½”) Connections – Ultra-compact for small combi boilers and tight spaces

• ✅ 130mm Flange Distance – Industry standard – direct replacement for most 15-series pumps

• ✅ AUTOADAPT Technology – Self-optimizing performance, no manual tuning needed

• ✅ Energy Class A (EEI ≤ 0.20) – Ultra-low power consumption (5–30W)

• ✅ 85% Energy Savings – Compared to older UPS/UNO pumps

• ✅ Night Setback Mode – Automatic reduction for DHW recirculation

• ✅ Alarm Relay Output – Remote fault signaling for home automation

• ✅ Automatic Air Purge – Self-venting during installation and operation

• ✅ LED Status Display – Color-coded for easy troubleshooting

• ✅ Dry-Running Protection – Prevents damage from water loss

• ✅ Ceramic & Graphite Bearings – Long service life (50,000+ hours)

• ✅ 4 Operating Modes – AUTOADAPT, Constant Pressure, Proportional Pressure, Constant Curve

• ✅ Ultra-Quiet Operation – < 40 dB – virtually silent (quieter than a library)

• ✅ Smallest Footprint – Fits anywhere

• ✅ Wet Rotor Design – Self-lubricating, maintenance-free

5. Technical Specifications