Provides advice regarding the design of heating and chilled water systems, where heating or cooling circuits are serving mainly forced convection heating or cooling coils as might be found in air handling units or fan assisted terminal units. Demonstrates what the priorities are for the design of such systems and indicates the effect of the commissioning process on the control of space conditions. The main purpose is to clarify these issues so that more cost effective designs and commissioning solutions can be considered. Presents the Guide in a style which answers the main questions posed by building services engineers with regard to the design and commissioning of pipework system.