Size

Sizing copper pipework

You need to size copper pipework according to the flow rate (L/s) through each section of pipework. You can use a friction loss chart to help you size the pipework for your heating or cooling system. Once you have determined the size of the copper pipework you can record the size of each section on a pipework sizing chart. The following diagram outlines the features of a pipework sizing chart that has been designed for sizing copper pipework.

An example of a sizing chart that is going to be used to size copper pipework.

The following demonstration steps through the process of sizing copper pipework for a domestic hydronic heating system.

Use the worked example's Back and Next navigation to view the demonstration.


 
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Worked example

Main run

The main pipework run describes the water flow rate through each section of pipework that makes up the hydronic heating system.

An example of a main run.

Friction loss chart

In this example the pipework is going to carry heated water. If you are sizing pipework that is going to carry chilled water, you will need to use the appropriate friction loss chart. Manufacturers often supply sizing information about their materials. This manufacturer’s friction loss chart specifies their copper pipework should be sized at a recommended pressure loss of 0.350 Pa/m.

An example of a friction loss chart that will be used to size the copper pipework.

Identify the flow rate through the first pipework section

We know that pipework section A–B has a water flow rate of 0.806 L/s. To help us identify the correct copper pipework size, we can draw a line across the friction loss chart from the 0.806 L/s flow rate.

A diagram that indicates a pipework section's water flow rate on a friction loss chart.

Identify the pressure loss

We know that the pipework has to be sized for a pressure loss of 0.350 Pa/m. We can now draw a line up the friction loss chart from the 0.350 Pa/m pressure loss rating.

A diagram that indicates a pressure loss on a friction loss chart.

Size the pipework section

If the two lines fall between two pipework diameters, use the greater value. For this example, we will size pipework section A–B at 40 mm.

A diagram that specifies the intersection of a water flow rate and a pressure loss. This intersection determines the size of the flexible ductwork.

Record the pipework size

We can now record the size of the pipework in the pipework sizing chart.


You can record the size of the copper pipework in your pipework sizing chart.

Size the remaining sections of pipework

Using this method, continue to size the remaining sections of pipework.


Size the remaining sections of pipework.

Now that you know how to size copper pipework, help Mike size the pipework for the following heating and cooling scenarios.

Mike the plumber.

The Smiths have contracted Mike the plumber to design a hydronic heating system for their alpine retreat.

Mike has started designing the installation and he has determined:

  • the water flow rates of the total area to be heated
  • the water flow rates of each room to be heated
  • the copper pipework layout on both floors of the house.

The next stage is for you to help Mike size the copper pipework.

Start the Smiths' hydronic heating pipework sizing activity.
Mike the plumber.

Crosby Incorporated has contracted Mike the plumber to complete the design of the heating and cooling system for its new multistorey development.

Crosby Incorporated's mechanical engineers have determined:

  • the location of the heating and chilling units
  • the layout of the pipework (two-pipe direct return)
  • the type of pipework material (copper)
  • the location of the air handling units on each floor.

The next stage is for you to help Mike size the copper pipework.

Start Crosby Incorporated's heated and chilled water pipework sizing activity.