Control valves in variable-flow systems
BSRIA has published new guidance to help designers avoid problems with the selection and application of control valves and assist with the design of energy-efficient variable-flow systems. The guidance is called ‘Selection of control valves in variable flow systems’ (BG 51/2014).
The design of control valves varies widely, and care should be taken to select the correct product for an application. The guide explains how to select and size conventional 2-, 3- and 4-port or pressure-independent control valves for the direct and indirect control of terminal devices such as radiators, fan-coil units, chilled beams, trench heaters, plate heat exchangers and calorifiers.
The proper sizing of control valves is vital to ensure comfort control by avoiding excessive temperature variations in the controlled media and to control the temperature differential so as to maximise energy efficiency.
The sections cover:
• matching control valve to terminal device;
• achieving effective modulating control;
• sizing control valves.