How to Design a Hot Water Recirculation System

Designing a hot water recirculation system can be one of the most challenging parts of the job for many engineers. When done correctly, the process can involve numerous iterations of calculations between pipe sizing and heat loss before the final results are realised.

Hot Water Recirculation Systems in High-Rise Buildings

Designing a hot water recirculation system can be one of the most challenging parts of the job for many engineers. When done correctly, the process can involve numerous iterations of calculations between pipe sizing and heat loss before the final results are realised.

This video demonstrates how simple it is to design a hot water recirculation system using h2x, and includes the following;

  • How to Set Calculation Parameters
    • Insulation type and thickness
    • Maximum velocities
    • Pipe materials
    • Delta T between flow and return
  • How to Add Hot Water Plant
  • How to Draw Pipes and Set Pipe Heights
  • How to Connect Fixtures and Valves
  • Calculation Results
    • Return system duty flow rate
    • Return system pressure loss
    • Return system heat loss
    • Balancing valve Kv value
    • Pipe peak flow rate
    • Pipe return flow rate
    • Pipe diameter
    • Pipe velocity
    • Pipe loading units
    • Fixture static pressure
    • Fixture dynamic pressure
    • Fixture Dead Legs

Tip - Press the box in the bottom right-hand corner of the video to go full screen!

If you'd like to learn more technical details about Hot Water System design, why not check out our blog post at the link below.

6 steps you must consider before designing your next hot water system

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Article Last Updated: February 21, 2025

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