Circulation Pumps

Detailed Information on Circulation Pumps

Circulation pumps are high-efficiency pumps that ensure the continuous recirculation of fluids in closed-loop heating, cooling, and domestic hot water systems. They provide the ideal solution for closed systems where high pressure is not required. Energy efficiency, silent operation, and long-lasting structure are the most prominent features of these pumps.

Pump Types

• Wet Rotor Circulation Pumps: Silent, maintenance-free, and the most widely used model in residential and commercial buildings.
• Dry Rotor Circulation Pumps: Designed for industrial systems requiring larger flow rates and higher head.
• Frequency Controlled (Inverter) Models: Provide energy savings and operate in automatic mode for variable flow requirements.

Operating Principle

In a closed-loop installation, kinetic energy is imparted to the fluid by the rotation of the pump impeller, circulating the fluid within the circuit. In wet rotor models, the motor operates in a specific liquid in contact with water, creating a silent and maintenance-free structure. Frequency-controlled models save energy by adjusting RPM according to system requirements.

Application Areas

• • Combi and boiler room systems
• • Central heating systems
• • Underfloor heating circuits
• • Chiller – cooling group circuits
• • Domestic hot water (boiler) circulation lines
• • Industrial closed-loop process systems
• • Solar energy systems

Material Structure

• • Body: Cast iron, brass, or stainless steel
• • Impeller: PPS, Noryl, or stainless steel
• • Shaft: Ceramic or stainless steel
• • Rotor Assembly: Liquid-lubricated structure in wet rotor models
• • Motor: Frequency-controlled (energy class IE4+) options

Performance Capacities

Circulation pumps are generally manufactured with:
• 1 – 80 m³/h flow rate
• 1 – 20 m head (lift)
• Suitable for 90°C – 120°C hot water
• 40 – 300 W power consumption (Wet rotor)
• IE4 energy class inverter options. They provide reliable and silent operation in residential, commercial, and industrial closed-loop systems.