BG 31-17 illustrated mechanical guide third edition cover_BSRIA Pubs cover 02/05/2017 09:11 Page 1 A BSRIA Guide www.bsria.co.uk The Illustrated Guide to Mechanical Building Services Third Edition By David Bleicher BG 31/2017 ACKNOWLEDGEMENTS The first edition of this publication (AG 15/2002) was written by Tom de Saulles and included considerable contribution from Gay Lawrence Race. The second edition (BG 31/2012) was written by David Bleicher. This third edition was updated by David Bleicher and James Parker. BSRIA would also like to thank the following organisations that kindly provided the photographs or diagrams which have made this illustrated guide possible: Airedale International Air Conditioning Ltd. Albion valves (UK) Ltd. Alfa Laval Ltd. Altecnic Ltd. AmbiRad Ltd. Armstrong Integrated Ltd. Clivet UK Ltd. Colt International Ltd. Crane Fluid Systems Daikin UK Ltd. DE-VI Electroheat Ltd. Displacement Design Ltd. Dravo Environmental Services Ltd. Elster Metering Ltd. - Now part of Honeywell Frenyer Ltd. Geoff Sumner Honeywell International Inc. Hudevad Ltd. Kamstrup Kensa Heat Pumps Kohlbach Holdings GmbH Marflow Hydronics Mitsubishi Electric Ormandy Ltd. Peter Brotherhood Ltd. Powrmatic Ltd. S&P Coil Products Siemens Building Technologies Spirotech UK Toshiba Air Conditioning Trox UK Ltd. TSI Instruments Ltd. Vortice Ltd. This publication was designed and produced by Joanna Smith. Final editorial control rested with BSRIA. The guidance given in this publication is correct to the best of BSRIA’s knowledge. However BSRIA cannot guarantee that it is free of errors. Material in this publication does not constitute any warranty, endorsement or guarantee by BSRIA. Risk associated with the use of material from this publication is assumed entirely by the user. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means electronic or mechanical including photocopying, recording or otherwise without prior written permission of the publisher. © BSRIA May 2017 ISBN 978-0-86022-758-8 Printed by Bishops THE ILLUSTRATED GUIDE TO MECHANICAL BUILDING SERVICES © BSRIA BG 31/2017 0 - BG 31-2017 Illustrated Mechanical guide - CONTENTS.indd 1 09/05/2017 13:32:46 PREFACE This illustrated guide provides basic reference information on mechanical building services systems for construction clients and professionals in other areas of the construction industry. The topics covered are: ¾ Heating ¾ Ventilation ¾ Air-conditioning ¾ Controls. For construction clients, this guide provides a simple insight into the main system options discussed during the briefing process and can consequently assist dialogue with the design team. It can also help clients to identify and raise technical questions which they feel are relevant to their organisation’s specific needs. For construction professionals, the guide provides a quick reference to building services systems and can assist their working knowledge of the subject. To ensure the guide is simple and quick to use, a brief introduction to each system is provided, followed by a list of key points. Photographs and simple drawings are used to help explain the appearance and operation of each system. It is acknowledged that the design team’s role includes assessing and recommending appropriate design solutions for a given project. This guide does not aim to provide a route for system selection other than pointing out typical applications for many of the systems covered. Since the previous edition of this guide, further information has been added on pumps, pipework, valves, heat networks, gas systems, ductwork, air handling units and commissioning along with updates of the original information. BSRIA has also published a companion guide BG 32/2014, The Illustrated Guide to Electrical Building Services – Third edition. This provides information on electrical systems including power supply and distribution, fire detection and alarm systems, security systems, lighting systems, uninterruptible power supplies and structured cabling. More detailed information on systems covered in this guide can be found in the following publications: ¾ BG 2/2009 The Illustrated Guide to Ventilation ¾ BG 1/2010 The Illustrated Guide to Mechanical Cooling ¾ BG 1/2008 The Illustrated Guide to Renewable Technologies ¾ BG 33/2014 The Illustrated guide to Hot and Cold Water Services ¾ BG 7/2009 Heat Pumps ¾ BG 2/2007 CHP for Existing Buildings. THE ILLUSTRATED GUIDE TO MECHANICAL BUILDING SERVICES © BSRIA BG 31/2017 BG 31-2017 The Illustrated guide to mechanical Building Services.indb Draft 1.indb 2 09/05/2017 13:01:59 CONTENTS Page OVERVIEW 1 Building design and building services 1 Location of building services 3 Thermal comfort 4 HEATING 5 Air and dirt removal 6 Pipework 7 Typical systems 8 Valves 10 Heat networks 12 Gas systems 13 Boilers 14 Low carbon heat 15 Radiators 16 Convectors 17 Underfloor heating 18 Radiant heating 19 Warm air unit heaters 21 VENTILATION 22 Natural ventilation 22 Powered window actuators 23 Single-sided ventilation 24 Cross ventilation 24 Stack ventilation 25 Stack and wind ventilators 26 Mechanical ventilation – Extract only 27 Mechanical ventilation – Supply only 28 Supply and extract systems 29 Mechanical ventilation with heat recovery 30 Ductwork 31 Air handling units 32 AIR-CONDITIONING SYSTEMS 33 Constant volume (CV) 36 Variable air volume (VAV) 37 Displacement ventilation 38 Fan coil units 39 Chilled ceilings 41 Chilled beams 42 Room-based heat pumps (Versatemp system) 43 Split systems 44 Variable refrigerant flow systems (VRF) 45 Chillers, dry coolers and cooling towers 46 Air diffusers 47 CONTROL SYSTEMS AND COMPONENTS 48 Analogue and direct digital control (DCC) systems 51 Building management systems (BMS) 52 Integrated control systems 53 COMMISSIONING, HANDOVER AND EVALUATION 54 INDEX 56 THE ILLUSTRATED GUIDE TO MECHANICAL BUILDING SERVICES © BSRIA BG 31/2017 BG 31-2017 The Illustrated guide to mechanical Building Services.indb Draft 1.indb 3 09/05/2017 13:01:59 BSRIA ILLUSTRATED GUIDE SET – SAVE OVER 45% BSRIA publishes a range of illustrated guides on key building services topics. They are ideal for those new to the industry, as an easy reference for experienced engineers or an aid to assist dialogue in project teams. Illustrated with simple line diagrams and photos, the guides demystify the subjects of: ¾ Mechanical Building Services ¾ Electrical Building Services ¾ Mechanical Cooling ¾ Ventilation ¾ Hot and Cold Water Services ¾ Renewable Technologies AVAILABLE IN HARD COPY OR PDF FROM THE BSRIA BOOKSHOP www.bsria.co.uk/goto/ill6 or Tel: +44 (0) 1344 465 529 THE ILLUSTRATED GUIDE TO MECHANICAL BUILDING SERVICES © BSRIA BG 31/2017 BG 31-2017 The Illustrated guide to mechanical Building Services.indb Draft 1.indb 4 09/05/2017 13:02:01 OVERVIEW – BUILDING DESIGN AND BUILDING SERVICES The design of a building will affect many of the costs which an operator will encounter during the life of a building. The building services can account for around 30% of the capital cost and 50% of the operating cost for a typical office building. It is therefore important that the services form OVERVIEW an integral part of the overall building concept to help ensure they will operate efficiently. Involving the specialist building services engineer at an early stage in the design process can help achieve this objective. If the services are not considered until a later stage, problems which could have been overcome by simple measures may require a more complex technical solution. A well-designed building may cost a little more initially, but the overall cost of ownership should be reduced. Life cycle costs of building services systems should be considered, as the cost-in-use element can form a large proportion of the total cost, outweighing the initial capital cost. Decisions about which services to incorporate into a building design require consideration of many factors including the following: ¾ Cost Both initial costs and life cycle costs. ¾ Level of thermal comfort required See overview: thermal comfort, page 4. ¾ Level of control required See control systems and components, page 48. ¾ Complexity What type of system is appropriate and will it be difficult to operate and maintain? For example a full air-conditioning system provides close control of air temperature and humidity, but this comes at a price. ¾ Noise levels Will heating, ventilation and air-conditioning plant adversely affect noise levels in occupied areas? What about noise from outside the building? The noise rating (NR) is a European measure of sound levels which relates to the sensitivity of the human ear. It is often used to specify an acceptable interior or exterior sound level, for example NR 35 to 40 for offices, NR 20 for a concert hall. ¾ Adaptability and flexibility To meet possible future requirements. ¾ Energy use Mechanical building services plant can account for a major part of a building’s energy use. ¾ Plant space Air-conditioning systems can require a large amount of space to accommodate the refrigeration and air handling plant. Access for operation, maintenance and replacement must be considered (see overview: location of building services, page 3). It is not always possible to design a building that can utilise all possible energy saving measures. Urban noise and pollution may dictate the need for sealed buildings incorporating mechanical ventilation or air- conditioning systems. The activities in some buildings can also necessitate air-conditioning to offset a high internal heat gain. THE ILLUSTRATED GUIDE TO MECHANICAL BUILDING SERVICES 1 © BSRIA BG 31/2017 BG 31-2017 The Illustrated guide to mechanical Building Services.indb Draft 1.indb 1 09/05/2017 13:02:01 HEATING - INTRODUCTION Buildings lose heat by three mechanisms: ¾ Fabric losses – heat that transfers through the floor, walls, roof and windows of a building. They can be reduced by providing insulation and double-glazing. ¾ Ventilation losses – heat that is lost when stale, warm air is exhausted from buildings. They can be reduced by only ventilating to the degree necessary for health and comfort of building occupants, and making use of heat recovery (see page 29).