Variable flow pipework systems: valve solutions (KS7S)

Chris Parsloe

• Publisher: The Chartered Institution of Building Services Engineers
• Year: 2009
• eBook ISBN: 9781906846091
• Topic: Technology & Engineering
• Subtopic: Construction & Architectural Engineering
• Index: Technology & Engineering

This publication forms a supplement to CIBSE Knowledge Series KS7: Variable flow pipework systems (CIBSE, 2006). It explains how to design recirculating heating and cooling water systems incorporating variable speed pumps utilising two alternative valve solutions not covered in KS7, these being: — centralised valve modules— pressure independent control valves (PICVs).KS7 explains the main principles underlying the design of variable flow pipework systems, and provides two alternative approaches to system design. These are: — self-balancing arrangements in which terminal units are connected from reverse return branches, and pump speed is controlled to maintain constant pressure differentials across the terminals— designs incorporating differential pressure control valves (DPCVs) in which the system is laid out as a conventional 2-pipe flow and return configuration but with DPCVs strategically located on sub-branches in order to minimise the pressure differentials across downstream 2-port control valves.Knowledge Series KS9: Commissioning variable flow pipework systems (CIBSE, 2007) describes the commissioning procedures for variable flow systems designed using these two methods.Both of the above methods give satisfactory results when used on large re-circulating heating and cooling water pipework systems. Furthermore, both systems can be designed and specified using a variety of alternative valve products from different suppliers.Since the publication of KS7 and KS9, valve technology has advanced to the point where there are now commonly available products that help to simplify the design of variable flow systems. Hence, the need for this supplement, which builds on the principles explained in KS7 but offers additional design approaches both of which have proved successful on actual projects.

Table of contents

• KS7S Variable flow pipework systems: valve solutions OFC
• Contents
• 1 Introduction
• 2 Centralised valve module solution
• 3 Pressure independent control valve solution
• References and bibliography