1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS 6644:2011Incorporating Corrigendum No. 1Specification for theinstallation and maintenanceof gas-fired hot waterboilers of rated inputsbetween 70 kW (net) and1.8 MW (net) (2nd
2、and3rd family gases)Publishing and copyright informationThe BSI copyright notice displayed in this document indicates when the documentwas last issued. The British Standards Institution 2013Published by BSI Standards Limited 2013ISBN 978 0 580 81055 8ICS 91.140.65The following BSI references relate
3、to the work on this standard:Committee reference GSE/30Draft for comment 11/30229801 DCPublication historyFirst published March 1986Second edition, July 1990Third edition, October 1991Fourth edition, July 2005Fifth (present) edition, November 2011Amendments issued since publicationDate Text affected
4、January 2013 C1: See Foreword.BS 6644:2011 BRITISH STANDARDContentsForeword ii1 Scope 12 Normative references 23 Terms and definitions 34 Competence and design considerations 55 Selection of boiler, materials and components 86 Installation 107 Inspection, commissioning and servicing 38AnnexesAnnex A
5、 (informative) Basis for the provision of combustion and cooling air toboiler houses and rooms in which commercial boilers are installed 42Annex B (informative) Fan diluted flues 46Annex C (informative) Checks to be carried out on the boiler prior tocommissioning 47Annex D (informative) Typical live
6、 run checks 48Annex E (normative) Combustion products analysis 49Annex F (informative) Best practice guide to the dispersion of combustionproducts 50Bibliography 55List of figuresFigure 1 Example layout showing expansion vessels for each individualboiler 18Figure2Typical balanced compartment ventila
7、tion location 29Figure 3 Condensate trap 32Figure 4 Siting of a natural draught flue terminal 35Figure B.1 Uncorrected chimney heights 47List of tablesTable 1 Registration and approval bodies by country/territory 6Table 2 Competence requirements by country/territory 6Table 3 Safety valve sizes (open
8、 vented systems only) 13Table 4 Cold feed pipe sizes 15Table 5 Open vent pipe sizes 15Table 6 Minimum air vent free-area for Type C boilers installed in anenclosure 25Table 7 Mechanical ventilation flow rates 28Table A.1 Cooling air for a boiler not fitted with a draught diverter 43Table A.2 Cooling
9、 air for a boiler fitted with a draught diverter 44Table A.3 Natural ventilation for a boiler not fitted with a draughtdiverter 44Table A.4 Natural ventilation for a boiler fitted with a draught diverter 45Table A.5 Mechanical ventilation flow rates 46Table E.1 Concentrations of (CO2)Nin Group H, P
10、and B gases 49Summary of pagesThis document comprises a front cover, an inside front cover, pages i to iv,pages 1 to 58, an inside back cover and a back cover.BRITISH STANDARD BS 6644:2011 The British Standards Institution 2013 iForewordPublishing informationThis British Standard is published by BSI
11、 Standards Limited, under licence fromThe British Standards Institution, and came into effect on 30 November 2011. Itwas prepared by Technical Committee GSE/30, Gas installations (1st, 2nd and 3rdfamily gases). A list of organizations represented on this committee can beobtained on request to its se
12、cretary.SupersessionThis British Standard supersedes BS 6644:2005+A1:2008, which is withdrawn.Information about this documentThis is a full revision of the standard and introduces the following principalchanges: system requirements in accordance with BS EN 12828 have been added; details on condensin
13、g appliances and condensate removal have been added; the appliance classification types have been updated.NOTE The general installation requirements contained within this standard mayalso be applied to gas installations supplied with LPG/air mixtures, e.g. that are usedon the Channel Islands (see th
14、e Gas Safety (Installation and Use) Regulations 1994 1and the Health and Safety (Gas) (Guernsey) Ordinance 2006 2). However, particularattention needs to be given to ensure that any gas equipment being installed hasbeen appropriately converted and is suitable for the gas being supplied.Use of this d
15、ocumentThe start and finish of text introduced or altered by Corrigendum No. 1 isindicated in the text by tags.Presentational conventionsThe provisions of this standard are presented in roman (i.e. upright) type. Itsrequirements are expressed in sentences in which the principal auxiliary verb is“sha
16、ll”.Commentary, explanation and general informative material is presented insmaller italic type, and does not constitute a normative element.Contractual and legal considerationsThis publication does not purport to include all the necessary provisions of acontract. Users are responsible for its corre
17、ct application.Compliance with a British Standard cannot confer immunity from legalobligations.In particular, attention is drawn to the following regulations, which might beamended from time to time. The commentary in this British Standard reflectsthe state of the regulations in 2011.The Gas Safety
18、(Installation and Use) Regulations 1994, as amended and appliedby the Gas Safety (Application) Order (Isle of Man) 1996 1The Health and Safety (Gas) (Guernsey) Ordinance 2006 2The Gas Safety (Installation and Use) Regulations 1998 3The Gas Safety (Installation and Use) (Northern Ireland) Regulations
19、 2004 4The Gas Appliances (Safety) Regulations 1995 5BRITISH STANDARDBS 6644:2011ii The British Standards Institution 2013The Boiler (Efficiency) Regulations 1993, as amended 6The Building Regulations 2000, as amended 7The Building (Scotland) Regulations 2004 8The Building Regulations (Northern Irel
20、and) Statutory Rules 2000 9The Pressure Equipment Regulations 1999 10The Water Supply (Water fittings) Regulations 1999 11The Health and Safety at Work etc. Act 1974 12The Electricity at Work Regulations 1989 13Clean Air Act 1993 14The Asbestos (Prohibitions) Regulations 1992, as amended 15The Dange
21、rous Substances and Explosive Atmospheres Regulations 2002 16The Environment Act 1995 17BRITISH STANDARD BS 6644:2011 The British Standards Institution 2013 iiiBRITISH STANDARDBS 6644:2011This page deliberately left blankiv The British Standards Institution 20131 ScopeThis British Standard specifies
22、 requirements for the installation, including design,inspection, commissioning and maintenance, of gas-fired hot water boilers ofnet rated heat inputs exceeding 70 kW but not exceeding a net heat inputof 1.8 MW. Groups of boilers with individual net heat inputs of 70 kW or less,but with aggregate ne
23、t heat inputs in excess of 70 kW, are also covered.This British Standard is applicable to the installation of boilers that are designedto utilize normally distributed gases of Group H of the second family(e.g. natural gas), and gases of Group P (e.g. propane) and Group B(e.g. butane) of the third fa
24、mily. For the purposes of this installation standard,LPG/air mixtures are regarded as third family gases.This British Standard is applicable to the installation of the following gas-firedhot water boilers:a) boilers supplied as a complete assembly and conforming to BS EN 656 orBS 5978 (all parts);b)
25、 boilers supplied as a complete assembly and used in multiple boilerinstallations where the total net heat input exceeds 70 kW and conformingto BS EN 297, BS EN 483 or BS EN 677;c) boilers and burners delivered separately and assembled on site, comprising:1) a boiler shell conforming to BS EN 303-1,
26、 BS EN 12952 (all parts),BS EN 12953 (all parts), BS 779, BS 855 or BS 2790;2) a burner conforming to BS EN 676;3) an assembly conforming to BS EN 303-3 orBS 5978-1andBS 5978-3.NOTE 1 It is recognized that the design, inspection and commissioning requiredifferent levels of competence (see 4.1 and 4.
27、2). Where all of these tasks areperformed by same person, that person has to have the necessary levels ofcompetence for each task.NOTE 2 Although this British Standard does not contain any requirements forindustrial processes, the general principles can be applied.NOTE 3 The general principles of th
28、is British Standard with respect to hot watercircuits can be used for boilers exceeding 1.8 MW net heat input (2 MW gross heatinput). For installations exceeding 1.8 MW net heat input see IGEM/UP/10 18.NOTE 4 The ratio of gross to net heat input is approximately 1.11:1 for Group H(natural gas), 1.09
29、:1 for Group P (propane) and 1.08:1 for Group B (butane).It is also applicable to installations that have been converted from burning otherfuels to gas-firing.This British Standard is not applicable to:i) the installation of any heating or hot water supply system associated withthe boiler installati
30、on;ii) the installation of gas cushion systems (non diaphragm expansion vessels)intended to pressurize the hot water circuit; oriii) installations in hazardous areas, as defined in The Dangerous Substancesand Explosive Atmospheres Regulations (DSEAR) 2002 16, other than thoseclassified as Zone 2 NE,
31、 guidance on which is given in IGEM/SR/25 19 andIGEM/UP/16 20.BRITISH STANDARD BS 6644:2011 The British Standards Institution 2013 12 Normative referencesThe following referenced documents are indispensable for the application ofthis document. For dated references, only the edition cited applies. Fo
32、r undatedreferences, the latest edition of the referenced document (including anyamendments) applies.BS 779, Specification for cast iron boilers for central heating and indirect hotwater supply (rated output 44 kW and above)1)BS 855, Specification for welded steel boilers for central heating and ind
33、irect hotwater supply (rated output 44 kW to 3 MW)BS 1212-1, Float operated valves Part 1: Specification for piston type floatoperated valves (copper alloy body) (excluding floats)BS 1212-2, Float operated valves Part 2: Specification for diaphragm type floatoperated valves (copper alloy body) (excl
34、uding float)BS 1212-3, Float operated valves Part 3: Specification for diaphragm type floatoperated valves (plastic bodied) for cold water services only (excluding floats)BS 2790, Specification for design and manufacture of shell boilers of weldedconstruction2)BS 5440-2:2009, Flueing and ventilation
35、 for gas appliances of rated input notexceeding 70 kW net (1st, 2nd and 3rd family gases) Part 2: Specification forthe installation and maintenance of ventilation provision for gas appliancesBS 5854:1980, Code of practice for flues and flue structures in buildingsBS 5978 (all parts), Safety and perf
36、ormance of gas-fired hot water boilers(60 kW to 2 MW input)BS 7671, Requirements for electrical installations IET Wiring Regulations(Seventeenth edition)BS EN 297, Gas-fired central heating boilers Type B11and B11BSboilers fittedwith atmospheric burners of nominal heat input not exceeding 70 kWBS EN
37、 303-1, Heating boilers Part 1: Heating boilers with forced draughtburners Terminology, general requirements, testing and markingBS EN 303-3, Heating boilers Part 3: Gas-fired central heating boilers Assembly comprising a boiler body and a forced draught burnerBS EN 483, Gas-fired central heating bo
38、ilers Type C boilers of nominal heatinput not exceeding 70 kWBS EN 656:2000, Gas-fired central heating boilers Type B boilers of nominalheat input exceeding 70 kW but not exceeding 300 kWBS EN 676, Automatic forced draught burners for gaseous fuelsBS EN 677, Gas-fired central heating boilers Specifi
39、c requirements forcondensing boilers with a nominal heat input not exceeding 70 kWBS EN 1443:1999, Chimneys General requirementsBS EN 1856-1, Chimneys Requirements for metal chimneys Part 1: Systemchimney productsBS EN 1856-2, Chimneys Requirements for metal chimneys Part 2: Metal linersand connecti
40、ng flue pipes1)BS 779 has been partially superseded by BS EN 303-1 and BS EN 303-4.2)BS 2790 has been partially superseded by BS EN 12953-1, BS EN 12953-2,BS EN 12953-5, BS EN 12953-6 and BS EN 12953-8.BRITISH STANDARDBS 6644:20112 The British Standards Institution 2013BS EN 1993-3-2, Eurocode 3 Des
41、ign of steel structures Part 3-2: Towers, mastsand chimneys ChimneysBS EN 12952 (all parts), Water-tube boilers and auxiliary installationBS EN 12953 (all parts), Shell boilersBS EN 13076, Devices to prevent pollution by backflow of potable water Unrestricted air gap Family A, type ABS EN 13077, Dev
42、ices to prevent pollution by backflow of potable water Air gap with non-circular overflow (unrestricted) Family A, type BBS EN 13831, Closed expansion vessels with built in diaphragm for installation inwaterBS EN 13959, Anti-pollution check valves DN 6 to DN 250 inclusive Family E,type A, B, C and D
43、BS EN ISO 4126-1, Safety devices for protection against excessive pressure Part 1: Safety valvesBS EN ISO 10380:2003, Pipework Corrugated metal hoses and hose assembliesN1 INSTITUTION OF GAS ENGINEERS AND MANAGERS. Gas installationpipework, boosters and compressors on industrial and commercial premi
44、ses.IGEM/UP/2. London: 1994. ISBN 0717700577.N2 UKLPG. Code of Practice 24: Part 6 The Use of Propane in Cylinders atCommercial and Industrial Premises. May 2000.N3 UKLPG. Code of Practice 22: LPG piping systems: design and installation.2002.3 Terms and definitionsFor the purposes of this British St
45、andard, the definitions given in BS EN 297,BS EN 483, BS EN 656, BS EN 677, BS EN 303-1, BS EN 303-3, BS EN 12952(all parts), BS EN 12953-1, BS 5978 (all parts) and the following apply.3.1 automatic natural draught burnernatural draught burner in which, starting from the completely shut-downconditio
46、n, the start-gas flame is established and the main gas valve(s) actuatedby the control without manual interventionNOTE Automatic burners can have pilots that are either interrupted orintermittent.3.2 bank of boilersgroup of two or more boilers connected to common flow and return pipes3.3 boiler hous
47、ededicated building for the installation of boilers and ancillary boiler plant3.4 boiler roomdedicated room within a building for the installation of boilers and ancillaryboiler plant3.5 balanced compartmentboiler house/room or enclosure for one or more gas appliances, specificallydesigned to draw i
48、ts combustion air from a point adjacent to the point at whichthe products of combustion are discharged, the inlet and outlet being sodisposed that wind effects are substantially balancedBRITISH STANDARD BS 6644:2011 The British Standards Institution 2013 33.6 condensing boilerboiler in which, under
49、normal operating conditions, the water vapour in thecombustion products is totally or partially condensed in order to make use ofthe latent heat in the water vapour for heating purposes3.7 coefficient of discharge, Kdvalue of actual flowing capacity (from tests) divided by the theoretical flowingcapacity (from calculations)3.8 derated coefficient of discharge, Kdrcoefficient of discharge, Kd, multiplied by 0.9, i.e. Kdr=
