CIRCULATION PUMPS

Union-connection and flanged circulation pumps for central heating, underfloor heating, combi boilers, and domestic hot water circuits: variable frequency drive (VFD) Wilo, Grundfos, and DAB models.

Subcategories

Products (55)

DAB Evoplus 40/180XM Variable Frequency Drive Circulation Pump, 180 mm, for 18–25,000 Boilers, 4.2 m, 7.5 m³/h – $509.46
DAB Evoplus B 120/250 Variable-Speed Flanged Circulation Pump, DN 40, 40 m, 220 V – $2,684.72
DAB Evoplus Lite 60/180-32 Variable Frequency Drive Circulation Pump, Union Connection, 2", 180 mm – $872.53
DAB Evosta2 40-70 Variable-Speed Circulation Pump, 130 mm, 40,000–60,000 kcal/h Boiler, 6.9 m, 3.6 m³/h – Request a quote (out of stock)
DAB Evosta3 40-180 Variable-Speed Circulation Pump, 180 mm, for 18,000–25,000 kcal/h Boilers, 4 m, 2.9 m³/h – $215.48
Duca Cosmo 25-8 Variable-Speed Circulation Pump, 180 mm, 8 m – Request a quote (out of stock)
Forza FRZ-SXR 25-6-130 Circulation Pump, 3-Speed, 130 mm – $70.00
GRS25/8 Hot Water Circulation Pump (25-8-180) – $118.87
Grundfos ALPHA1 25-40 (180 mm) VFD Circulation Pump for 18,000–25,000 kcal/h Boilers, 4 m, 2.6 m³/h – $259.17
Grundfos ALPHA2 25-40 (180 mm) Circulation Pump with VFD, for 18,000–25,000 kcal/h Boilers, 4 m, 2.6 m³/h – $331.32
Grundfos ALPHA3 15-40 (130 mm) Variable Frequency Drive Circulation Pump, 18,000–25,000 kcal/h Boilers, 4 m Head, 2.6 m³/h – Request a quote (out of stock)
Grundfos MAGNA1 25-40 (180 mm) VFD Circulation Pump for 60–80,000 Boiler, 4 m, 6.2 m³/h – $393.91
Grundfos MAGNA1 32-120 F (220 mm) Variable-Speed Circulation Pump for 200,000-300,000 Boilers, 12 m, 17 m³/h – $1,058.04
Grundfos UPS2 25-80 Variable-Speed Circulation Pump, 180 mm, 40,000–60,000 kcal/h Boiler, 8 m, 5.6 m³/h – Request a quote (out of stock)
Grundfos UPS 25-40 N 180 Circulation Pump, 4 m, 3 m³/h – Request a quote (out of stock)
Kentaş AUTO 25-6/130 Variable-Speed Circulation Pump, 45 W – Request a quote
Leo Inline Centrifugal Circulation Pump, 0.50 HP, 1 1/4" – Request a quote (out of stock)
Master ACR 40/250.12 Flanged Circulation Pump – Request a quote (out of stock)
Master EVOMAG 25/180.10 Union-End Circulation Pump, 180 mm, 12 m³/h, 10 m, 185 W, 1.1/2'' – Request a quote (out of stock)
Master EVOMAG 40/220.07 Flanged Circulation Pump, 220 mm, DN40, 17 m³/h, 7 m, 185 W – Request a quote (out of stock)
Micra APF 25-6-130 Variable-Speed Circulation Pump, Combi Boiler, Boiler, 6 m, 3 m³/h – Request a quote (out of stock)
Nortek FLS 40-250 M Variable-Speed Flanged Circulation Pump, DN 40, 220V – $1,260.00
Nortek SRF 25-130 VFD Circulation Pump, Union Connection, 1-1/2'', 250mm – $180.00
Regen RGN 50-300 Single-Phase Flanged Circulation Pump – Request a quote (out of stock)

Brands: DAB · Duca · Forza · Grundfos · Kentaş · Leo · Master · Micra · Nortek

What does a circulation pump do?

Circulation pumps are pumps that circulate water between the boiler, radiators, underfloor heating pipes, fan coils, or solar collectors in closed-loop heating and cooling systems. Their purpose is not to pump water to a height, but to overcome the frictional resistance of the pipes and fittings in the circuit so that water flows consistently. For this reason, their head is low while their quietness and energy efficiency are high. In domestic hot water lines, recirculation pumps are also used to deliver hot water to taps without a wait.

Types of circulation pumps

Union-connection (threaded) circulation pumps: Compact models for detached houses, apartments, and small boiler rooms.
Flanged circulation pumps: For central systems in apartment blocks, housing estates, and commercial buildings.
Inline circulation pumps: Centrifugal models that connect directly into the pipework.
Variable frequency drive (VFD) models: Significantly reduce energy consumption by adjusting speed to match circuit demand.
Bronze and stainless steel body models: Corrosion-resistant options for drinking and domestic hot water recirculation.

How to choose the right pump?

The most practical starting point is the capacity of the area to be heated or the boiler; many products indicate the suitable capacity range in their name with phrases such as "for 18–25,000 boiler". Codes such as "25-6-130" in product names typically indicate the connection size (DN25), the maximum head (6 m), and the center-to-center installation length between unions (130 mm). When replacing an existing pump, matching the installation length (130 or 180 mm) allows a like-for-like swap without modifying the pipework. For larger systems, flow rate and head should be determined by an HVAC engineer's calculation.

Installation and maintenance

Circulation pumps must be installed with the motor shaft horizontal, and the terminal box must not face downward. After filling the system, the pump and radiators must be bled; running with air causes noise and efficiency loss. In pumps that have been idle for a long time, the shaft may seize due to limescale; check that the pump turns freely at the start of the heating season.

Frequently asked questions

Is there a circulation pump inside a combi boiler?

Most combi boilers have a built-in pump. A separate circulation pump may be required for underfloor heating or additional heating circuits.

Should I choose 130 mm or 180 mm?

This dimension is the center-to-center installation length between the pump's two unions. Measuring your existing pump and selecting a model with the same dimension makes replacement straightforward.

What is the advantage of a VFD pump?

As valves in the circuit are throttled, the pump reduces its speed, lowering both electricity consumption and flow noise.

Can a circulation pump be used instead of a booster pump?

No. Circulation pumps are low-head recirculating pumps; a booster pump is required to supply water to taps under pressure.

What should I do if the pump is noisy?

First bleed the system and the pump; if the noise continues, the speed setting may be too high or the bearings may be worn.