Water pump WILO Star-Z 20/4-3 for domestic hot water circulation, model 4081193

WILO Star-Z 20/4-3 is a circulation pump designed for domestic hot water (DHW) systems to maintain stable temperature and reduce waiting time at taps. The pump is intended for continuous operation in residential and light-commercial hot water recirculation loops, providing reliable transport of heated water through piping networks to ensure quicker access to hot water and lower water waste.

Advantages

The WILO Star-Z 20/4-3 offers compact dimensions and a robust construction suitable for prolonged operation in hot water circulation systems. It delivers consistent flow rates and pressure heads appropriate for short to medium-length recirculation circuits while minimizing noise and energy consumption under typical domestic loads. The pump design supports straightforward integration into existing DHW loops and enables steady maintenance of set temperatures.

Suitable for

• Domestic hot water recirculation loops in single-family homes
• Small multi-family residential buildings
• Light commercial facilities requiring continuous hot water supply
• Retrofit installations to reduce cold-water waiting times at taps

Key specifications

• Application: Continuous circulation of domestic hot water
• Fluid handled: Hot water for sanitary use
• Nominal diameter and connection compatibility suitable for standard domestic piping
• Designed for continuous operation and regular thermal loads of DHW systems
• Compact footprint for easy installation in tight plant rooms or under sinks
• Low-noise operation appropriate for residential environments

How to use

Install the pump in the recirculation line following local plumbing codes and manufacturer mounting orientation. Ensure correct hydraulic connection with isolation valves and, where required, a check valve to prevent backflow. Provide electrical connection by a qualified electrician in accordance with local regulations and ensure proper earthing. Commission the pump by flushing the system, venting air, and verifying continuous circulation and temperature stability. Regularly inspect seals and connections and test operation after any maintenance or system changes.

Usage recommendations

Use the WILO Star-Z 20/4-3 in systems with appropriate water quality for potable hot water; avoid aggressive fluids or concentrations that may harm internal components. Schedule periodic inspections to check for leaks, noise changes or reduced flow, and follow local guidelines for electrical safety and plumbing practice during installation and servicing.