Circulator pumps
Circulator pumps: high-efficiency ECM technology for heating and DHW
Circulator pumps are the main component of heating, domestic hot water (DHW) preparation and cooling systems, ensuring constant circulation of the medium. Modern electronically commutated (ECM) motors with proportional pressure (Δp-c/Δp-v) control allow up to 80% less electricity to be consumed than older 3-speed pumps. All serious manufacturers (Grundfos, Wilo) fully comply with EU Ecodesign requirements - EEI ≤ 0.20 (class A).
Most popular series
- Grundfos ALPHA1 / ALPHA2 / ALPHA3 - for apartments, cottages and small commercial systems (up to ~40 kW). Simple button control + a reliable ECM motor.
- Grundfos MAGNA1 - for medium and larger systems (40-200 kW) with the AUTOadapt algorithm and modulating 0-10 V control from a BMS.
- Wilo Yonos PICO / MAXO - Grundfos' competing series with the same ECM technology and Δp-c/Δp-v modes.
- Wilo STAR-Z - a specialised DHW recirculation series (bronze + stainless steel body for drinking water).
How to select the size
The required flow rate is calculated as: Q = P / (1.163 × ΔT), where P is the heating capacity (kW) and ΔT is the difference between supply and return temperatures (°C).
Example: a 30 kW system with ΔT = 15 °C → Q = 1.7 m³/h. The head (H, m) depends on the pipework length and the hydraulic resistance of the equipment (heat exchangers, valves).
Δp-c vs Δp-v control modes
- Δp-c (constant differential pressure) - maintains an even system pressure. Suited to underfloor heating and systems without thermostatic valves.
- Δp-v (proportional pressure) - reduces the pressure as the flow decreases. Suited to a radiator system with thermostatic valves.
- AUTOadapt (Grundfos) - learns the system behaviour by itself and selects the optimal curve. Recommended if you are not sure which mode suits.
In the Amegata.lt range
We have the full range of Grundfos ALPHA1, ALPHA2, MAGNA1 (25/32/40/50/65 DN) and Wilo Yonos PICO, MAXO, Stratos. Threaded and flanged (DN40+ "F") versions - for larger heating substations. Competitive B2B prices, delivery within 24 hours, warranty according to the manufacturer's standards.
Common questions
Can an old UPS 25-40 be replaced with a MAGNA1 25-80?
Yes - the MAGNA1 25-80 (180 mm) is a direct modernisation option for the UPS 25-40. No pipework change is needed, and electricity consumption will fall by up to 80%.
Is it suitable for drinking water (DHW)?
Standard heating series ALPHA/MAGNA/Yonos - NO (cast iron body). DHW requires the Wilo STAR-Z or Grundfos ALPHA3 N / UPS N series with a bronze or stainless steel body.
What is the recommended installation position?
Horizontal rotor shaft, cable entry downwards or to the side. Vertical installation is prohibited. Before the pump - a strainer box (protection from the welding slag and dirt left in new systems).
What does the "180 mm" number in the name mean?
It is the installation length (flange-to-flange). The standard is 180 mm for small DN25/32, 220 mm - DN40 flange, 250 mm - DN50 flange. When replacing a pump, the length must match the existing pipework "gap".