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Hot Water Heating Systems - Online Design Application

Free online design tool for designing hot water heating systems - metric units.

This tool can be used to design hot water heating systems.

How to Use

  • Make a sketch of the system - something similar to the default sketch below. Custom drawings can be linked to the application - any global (http://..) or local (file://..) url should work
  • Tag the sections and add them to the hierarchical application structure below (after reset)
  • Add input data - power, preliminary dimensions, lengths, minor coefficients, temperature drop, and so on for each section
  • Modify the piping dimensions to achieve reasonable values for velocities and pressure drops
  • Select pump - the pump pressure must be larger than the highest accumulated pressure loss in the system
  • Balance the system - start with the endpoints - add balancing pressures until the pump pressures in the end points equals zero. Add balancing pressure in other sections if required.
  • Save the data file to your computer/network
  • dimensions, minor loss coefficients, viscosity, density, roughness, specific heat

Important! - this calculation is for the flow OR the return piping system. If the flow and return piping systems are more or less identical - as in the default example above - the total pressure loss through the system for the pump to handle is 2 times the calculated (as indicated in the graph).

If the flow and the return system are different - like with a reversed return system - then the flow and the return systems must be calculated separately. The total pressure loss for the pump to handle will be the summarized pressure loss for the flow and return system.

  • Note! - Since only half of the system is calculated - use only half the minor loss coefficients specified by suppliers in connection points between flow and return systems - typical in heating elements and/or in the central heater and pump.
  • When selecting balancing valves - keep the flow but double the calculated balancing pressure drop for systems with identical flow and return piping - and summarize if the piping is different.

Related Topics

  • Heating Systems

    Design of heating systems - capacities and design of boilers, pipelines, heat exchangers, expansion systems and more.

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