building engineering services association specification for: Domestic central Heating installation www.thebesa.com
building engineering services association acknowledgments Guide to good practice: Domestic central Heating installation the Besa wishes to record its sincere thanks to the following members of the drafting sub-committee, without whose direct input of knowledge, time and experience this publication would not have been produced. Bob mansfield ted rheams steve curtis ian Beard Paul Haddlesey - author graeme craig alan Keating secretary the Besa also wishes to acknowledge the input from Bsria, cibse, iop, oftec, energy saving trust, the Besa technical committee and other groups for their time, input and vetting. isbn 0-903783-51-7 First published 2004 by the Heating and Ventilating contractors association 2004 Besa besa Publications old mansion House eamont Bridge Penrith ca10 2BX 01768 860405 publications.info@thebesa.com. www.thebesa.com
building engineering services association Foreword Guide to good practice: Domestic central Heating installation When the Domestic Heating Design guide was first conceived in 1993 by a small technical committee from the then Home Heating group they had no idea that this recently updated guide would become the industry standard when designing heating and hot water systems. From the smallest dwelling up to and including semi-commercial installations, the design guide gives precise, easy to follow instructions on all aspects to be considered, allowing you to give your customer the best possible quotation for the installation. it was only natural therefore that following on this success it was not enough knowing how to design the system; we needed a standard on how to install it correctly. again with the expertise we have within the group and the technical department of the association, a specification has been drawn up on the installation of central heating water systems in residential dwellings and non-domestic buildings, of a residential nature. together with the Design guide this will provide a valuable tool for both the members and their clients, giving greater customer satisfaction and resulting in improved productivity and performance. raising the standards within our industry has always been one of the most important goals of the association and i firmly believe that members of the Heating and Plumbing services group now have the toolkit to do that professionally. i would like to express my personal thanks for all of the hard work, time and effort given by both members and staff of the association in producing these guides and the efforts by our industry in continually improving its standards. Bob mansfield, Former chairman, Heating and Plumbing services group Building engineering services association www.thebesa.com
CONTENTS Section 1 9 1.0 INTRODUCTION 9 1.1 OBJECTIVE 9 1.2 DESIGN 9 1.3 STANDARD OF WORKMANSHIP 9 1.4 SCOPE 9 1.5 PUBLICATION AND REVIEW 10 1.6 DESCRIPTION OF HEATING SERVICES 10 1.7 OPERATING CONDITION 10 1.8 DESCRIPTION OF WATER SERVICES 10 Section 2 WET CENTRAL HEATING 11 2.1 DESCRIPTION OF SERVICE 11 2.1.1 Operating Condition 11 2.1.2 Open Systems 11 2.1.3 Sealed Systems 11 2.1.4 Gravity Systems 12 2.1.5 Fully Pumped Systems 13 2.1.6 Under Floor Heating 14 2.1.7 Solar Heating 14 2.2 BOILERS 14 2.2.1 Boiler Selection 14 2.2.2 Regular/Standard Boiler 14 2.2.3 Combination Boiler 14 2.2.4 Condensing Boiler 15 2.2.5 Condensing Combination Boiler 21 2.2.6 Solid Fuel Gravity Boiler 21 2.2.7 Electric Boiler 21 2.2.8 Combined Heating and Power 22 2.3 FLUE TYPES 22 2.4 PUMPS AND CIRCUITS 24 2.4.1 Circulator Pumps 24 2.4.2 Circuits and Zones 25 2.5 SYSTEM CONTROLS 25 2.5.1 Time Switch 25 2.5.2 Full Programmer 25 2.5.3 Optimiser 25 2.5.4 Weather Compensator 26 2.5.5 Boiler Energy Manager 26 2.5.6 Boiler Interlock 27 2.5.7 Room Thermostat/Sensor 28 2.5.8 Night Set-back 28 2.5.9 Frost Thermostat 28 2.5.10 Cylinder Thermostat 29 2.5.11 Pipe Thermostat 29 2.5.12 Thermostatic Hot Water Limit Valve 29 2.5.13 Thermostatic Hot Water Mixing Valve 30 2.5.14 Radio Frequency Controls 30 4
2.6 THERMOSTATIC RADIATOR VALVES 30 2.7 AUTOMATIC BYPASS VALVE 31 2.8 HEAT EMITTERS 32 Section 3 HOT WATER SERVICE 33 3.1 DESCRIPTION OF SERVICE 33 3.1.1 Hot Water Service from Combi Boilers 33 3.1.2 Combined Primary Storage Units 34 3.1.3 Solar Water Heating 35 3.2 BOOSTED SUPPLIES 39 3.2.1 Booster Pumps 39 3.3 PRESSURISED SUPPLIES Unvented 41 3.3.1 Storage 42 Section 4 COLD WATER SERVICE 45 4.1 DESCRIPTION OF SERVICE 45 4.2 PRESSURE BOOSTER PUMP SETS 45 4.2.1 Booster Pumps 45 Section 5 5.1 FUELS NATURAL GAS 47 47 5.2 OIL 47 5.3 SOLID 47 5.4 SOLAR 47 5.5 COMBINED HEATING AND POWER 47 5.6 LIQUEFIED PETROLEUM GAS 47 Section 6 PIPEWORK UNDER FLOORS 49 Section 7 MATERIALS AND JOINTING METHODS 51 7.1 PIPING MATERIALS 51 7.2 SELECTION TABLES 51 7.3 STEEL PIPE JOINTING 53 7.3.1 Threaded 53 7.3.2 Welded 53 7.3.3 Flanged 53 7.3.4 Grooved 53 7.3.5 Press Fit 53 7.4 COPPER PIPE JOINTING 53 7.4.1 Compression 53 7.4.2 Capillary 54 7.5 PUSH FIT JOINTING 54 7.6 PRESS FIT JOINTING 54 7.7 PROPRIETARY SYSTEMS JOINTING 54 Section 8 COPPER PIPEWORK CONSTRUCTION AND ASSEMBLY 55 8.1 PIPING MATERIALS 55 8.1.1 Grades and Types 55 8.1.2 Finish 55 8.2 COMPRESSION JOINT AND FITTING ASSEMBLY 55 8.2.1 Compression Method 55 5
8.2.2 Compression Fittings 55 8.3 CAPILLARY JOINT AND FITTING ASSEMBLY 56 8.3.1 Capillary Method of Assembly 56 8.3.2 Capillary Fittings 56 8.4 PUSH FIT ASSEMBLY 56 8.4.1 Push Fit Method 56 8.4.2 Push Fit Fittings 56 8.5 PRESS FIT ASSEMBLY 56 8.5.1 Press Fit Method 56 8.5.2 Press Fit Fitting 56 8.6 PULLED BENDS 57 8.7 SUPPORT AND FIXINGS 57 8.8 EXPANSION AND CONTRACTION 57 8.8.1 Natural Flexibility 58 8.8.2 Expansion Devices 58 8.8.3 Anchors and Guides 58 8.8.4 Cold Draw 58 Section 9 PLASTIC PIPEWORK CONSTRUCTION AND ASSEMBLY 59 9.1 INTRODUCTION 59 9.2 APPLICATION SELECTION TABLE 59 9.3 JOINTING METHODS SELECTION 59 9.3.1 Threaded 60 9.3.2 Solvent Welding 60 9.3.3 Compression Fittings 61 9.3.4 Push-Fit 61 9.3.5 Press Fit 61 9.4 ELECTRICAL CONDUCTIVITY 61 9.5 EXPANSION AND CONTRACTION RATES 62 9.6 SUPPORTS 62 9.7 ULTRA-VIOLET LIGHT 63 9.8 MIXING OF PIPES AND FITTINGS 63 9.9 PRESSURE FLUCTUATION 63 9.10 PRESSURE AND TEMPERATURE RELATIONSHIP 63 9.11 LOCATION OF PIPEWORK 63 9.12 HIDDEN PIPEWORK 64 9.13 CHEMICAL CLEANING 64 9.14 HANDLING 64 9.15 PLASTIC PIPEWORK AND HEATING SYSTEMS 64 9.16 IDENTIFICATION 64 Section 10 STEEL PIPEWORK CONSTRUCTION AND ASSEMBLY 65 10.1 PIPING MATERIAL DETAILS 65 10.1.1 Pipe Finish 65 10.2 THREADED ASSEMBLY 65 10.2.1 Threaded Joints 65 10.2.2 Bends and Fittings 65 10.3 WELDED ASSEMBLY 65 10.3.1 Welding Methods 65 10.3.2 Welding Fittings 66 10.4 FLANGED ASSEMBLY 66 6
10.5 GROOVED ASSEMBLY 67 10.6 PRESS FIT ASSEMBLY 67 10.7 SUPPORT AND FIXINGS 67 10.8 EXPANSION AND CONTRACTION 68 10.8.1 Natural Flexibility 68 10.8.2 Expansion Devices 68 10.8.3 Anchors and Guides 68 10.8.4 Cold Draw 68 Section 11 STAINLESS STEEL PIPEWORK CONSTRUCTION AND ASSEMBLY 69 Section 12 GENERAL REQUIREMENTS CONSTRUCTION AND ASSEMBLY 71 12.1 MAIN EQUIPOTENTIAL BONDING 71 12.2 DRAINING 71 12.3 VENTING 71 12.4 EXPANSION AND CONTRACTION 71 12.5 PROTECTION 71 12.5.1 Physical 71 12.5.2 Corrosion 71 12.6 CONNECTIONS TO EQUIPMENT 72 12.6.1 Connections to Existing 72 12.6.2 Connections for Future Extensions 72 12.6.3 Pipe Freezing 72 12.7 EXTERNAL FABRIC PENETRATIONS 72 12.8 CONSTRUCTION AND ASSEMBLY PROCEDURES 72 12.8.1 Cleanliness 72 12.8.2 Pipe Sleeves 72 12.8.3 Alignment 73 12.8.4 Spacing and Clearances 73 Section 13 ACCESSORIES AND PIPELINE ANCILLARIES 75 13.1 GENERAL REQUIREMENTS 75 13.2 VALVE LOCATIONS AND FUNCTION 75 13.2.1 Isolating Valves 75 13.2.2 Regulating Valves 75 13.3 PIPELINE ANCILLARIES 75 13.3.1 Safety Valves 75 13.3.2 Ball Float Valves 75 13.3.3 Non-return Valves 76 13.3.4 Strainers 76 13.3.5 Instrumentation and Test Points 76 13.3.6 Pressure Gauges 76 13.3.7 Thermometers 76 13.4 IDENTIFICATION 76 13.4.1 Pipelines 76 13.4.2 Valves and Plant 76 Section 14 TESTING - HYDRAULIC 77 Section 15 THERMAL INSULATION 79 15.1 APPLICATION 79 15.1.1 Installation Considerations 79 7
15.1.2 Workmanship 80 15.2 TRACE HEATING 81 15.2.1 Pre-installation Guidelines 81 15.2.2 Installation 81 15.2.3 Heating Cable Connection 81 15.2.4 Heating Cable Testing 81 Section 16 FLUSHING, CLEANING AND WATER TREATMENT 83 16.1 APPLICATION 83 16.2 SYSTEM CLEANLINESS 83 16.2.1 Introduction 83 16.2.2 Delivery and Storage 83 16.2.3 During Installation 83 16.2.4 During Testing 83 16.2.5 Dynamic Flushing 83 16.2.6 Water Velocity 84 16.2.7 Flushing Existing Systems 84 16.3 FILLING SYSTEM 84 16.4 CHEMICAL CLEANING 85 16.4.1 Power Flush 85 16.5 WATER TREATMENT 86 Section 17 COMMISSIONING AND HAND OVER 87 17.1 APPLICATION 87 17.2 ORGANISATION AND MANAGEMENT 87 17.3 ACTIVITIES 87 17.3.1 Documentation 87 17.3.2 Prior to Commissioning 88 17.3.3 Pre-commissioning Cleaning 88 17.3.4 Static Commissioning Checks 88 17.3.5 Dynamic Commissioning Procedures 89 17.4 CIBSE/BSRIA CODES AND OTHER PUBLISHED PROCEDURES 90 17.4.1 Boiler Plant 90 17.5 OPERATION AND MAINTENANCE MANUALS 90 17.6 RECORD DRAWINGS 91 Section 18 BIBLIOGRAPHY AND SOURCES 93 18.1 REFERENCES 93 18.2 ABBREVIATIONS 95 18.3 MISCELLANEOUS 96 8