1、BRITISH STANDARD BS 7977-2:2003 Incorporating Corrigendum No. 1 Specification for safety and rational use of energy of domestic gas appliances Part 2: Combined appliances: Gas fire/back boiler ICS 91.140.10; 91.140.65; 97.100.20 BS 7977-2:2003 This British Standard was published under the authority
2、of the Standards Policy and Strategy Committee on 14 May 2003 BSI 13 June 2003 The following BSI references relate to work on this British Standard: Committee reference GSE/36 Draft for comment 95/717426 DC ISBN 0 580 41511 2 Committees responsible for this British Standard The preparation of this B
3、ritish Standard was entrusted to Technical Committee GSE/36, Independent gas-fired space heaters, upon which the following bodies were represented: Calor Gas Ltd. Consumer Policy Committee of BSI Department of Trade and Industry (Consumer Safety Unit) Department of the Environment Transport and Road
4、s (represented by the Building Research Establishment) Electricity Association Royal Society for the Prevention of Accidents Society of British Gas Industries Amendments issued since publication Amd. No. Date Comments 14517 Corrigendum No. 1 13 June 2003 Changes to title and supersession details in
5、national forewordBS 7977-2:2003 BSI 13 June 2003 i Contents Page Committees responsible Inside front cover Foreword iii 1S c o p e 1 2 Normative references 1 3T e r m s a n d D e f i n i t i o n s 2 3.1 Appliance and parts 2 3.2 Parts of the appliance conveying gas to the burners 2 3.3 The burner 3
6、3.4 Burner control systems 4 3.5 Construction 4 3.6 Auxiliary equipment 5 3.7 Gases 5 3.8 Appliance performance 7 3.9 Gas combustion 8 3.10 lint assessment 9 4 Classification of appliances 9 4.1 Classification according to the nature of the gases used (categories) 9 4.2 Conversion to different gases
7、 9 5 Construction 10 5.1 Materials and method of construction 10 5.2 Accessibility for maintenance and use 10 5.3 Connections to the gas and water pipes 10 5.4 Flue system 11 5.5 Soundness 11 5.6 Supply of combustion air and evacuation of the combustion products 12 5.7 Assembly 12 5.8 Electrical equ
8、ipment 12 5.9 Operational safety in the event of fluctuation, interruption and restoration of the auxiliary energy 12 5.10 Confirmation of operation 12 5.11 Requirements for adjusting, control and safety devices 13 5.12 Burners 18 6 Test conditions 19 6.1 Test gases 19 6.2 Conditions of test 21 7 Re
9、quirements and test methods 23 7.1 Soundness 23 7.2 Heat input 25 7.3 Limiting temperatures 27 7.4 Ignition-cross lighting and flame-stability 29 7.5 Delayed ignition 31 7.6 Control devices 31 7.7 Combustion 32 7.8 Lint assessment 35 7.9 Guarding (Fires only) 36 7.10 Spillage monitoring 37 7.11 Cycl
10、ic use test fire only 39 7.12 Products clearance 40 7.13 Flame supervision device 40 7.14 Useful efficiency at nominal heat input 42BS 7977-2:2003 ii BSI 13 June 2003 Page 7.15 Useful efficiency at part load (back boiler only) 44 7.16 Hydraulic resistance 46 7.17 Stability of the fire 47 7.18 Thermo
11、stats and water temperature limiting devices 47 8 Marking and instructions 48 8.1 General 48 8.2 Appliance marking 48 8.3 Dress guard 48 8.4 Warning labels 48 8.5 Packaging 48 8.6 Name badge 48 8.7 User instructions 49 8.8 Installation instructions 49 8.9 Conversion instructions 50 Annex A (normativ
12、e) Lint Method of test for resistance to airborne lint 67 Annex B (informative) Composition of the gas circuit 69 Annex C (informative) GAD essential requirements guide 72 Bibliography 74 Figure 1 Test box and flue 51 Figure 2 Collecting hood 52 Figure 3 Apparatus for measuring floor and wall temper
13、atures 54 Figure 4 Probe for dress guard test 55 Figure 5 Atmosphere sensing test room 56 Figure 6 Gas fire efficiency test rig 57 Figure 7 Sealing plate 58 Figure 8 Sampling probe 59 Figure 9 Mean specific heat of combustion products 60 Figure 10 Boiler test rig 61 Figure 11 Hydraulic resistance 63
14、 Figure 12 Position of baffle with respect to lint generator outlet duct 64 Figure 13 Lint generator 65 Figure 14 Lint filter 66 Figure B.1 Direct ignition of the main burner 69 Figure B.2 Ignition of the main burner by an ignition burner (see Clause 7.2.6)7 4 Figure B.3 Alternating ignition burner
15、71 Table 1 Classification of gases 9 Table 2 Gas valves for semi-automatic control systems 15 Table 3 Gas valves for automatic control systems with start-gas ignition 16 Table 4 Characteristics of the test gases gas dry at 15 C and 1,013.25 mbar 20 Table 5 The calorific values of the third family te
16、st gases 20 Table 6 Test pressure (mbar) 21 Table 7 (CO 2 ) Nfor test gases 33 Table 8 Products discharge times 39 Table 9 Gas fire efficiency 42 Table 10 Test gas data 43 Table 11 Useful boiler efficiency 43BS 7977-2:2003 BSI 13 June 2003 iii Foreword This standard has been prepared under the direc
17、tion of the Engineering Section Board, E/-, and is a revision of BS 5258-8:1989 and BS 6332-3:1984, all of which will be withdrawn, on publication of this standard. Matters related to quality assurance systems, tests during production and to certificates of conformity of auxiliary devices are not de
18、alt with. The test gases, test pressures and appliance categories specified in this standard are in accordance with those specified in BS EN 437. A Guide to the clauses of this British Standard addressing the Essential Requirements of the Gas Appliance Directive (GAD) is given in Annex C. In particu
19、lar attention is drawn to the following: The Gas Appliances (Safety) Regulations 1995 SI No. 16291. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard does not of itself confer
20、 immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pages i to iv, pages 1 to 74, an inside back cover and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued.iv blankBS 7977-2:2003
21、 BSI 13 June 2003 1 1 Scope This standard specifies the requirements and methods of test for the construction, safety, performance, classification and marking of gas-fired appliances consisting of a back boiler and a gas fire. These appliances are intended for installation with a governed or regulat
22、ed gas supply. This standard applies to open flued appliances using 2 ndand/or 3 rdfamily gases only. This standard does not apply to: back circulators; catalytic combustion appliances; appliances in which the supply of combustion air, or the movement of convected air, is achieved by mechanical mean
23、s; appliances intended for direct heating of sanitary water; gas fires with a range-rating capability. This standard only covers type testing. 2 Normative references The following referenced documents are indispensible for the application of this document. For dated references, only the edition cite
24、d applies. For undated references, the latest edition of the referenced document (including any amendments) applies. BS 1179:1967, Glossary of terms used in the gas industry. BS 5258-8:1980, Safety of domestic gas appliances Combined appliances: Gas fire/back boiler. BS EN 88:1991, Pressure governor
25、s for gas appliances. BS EN 125:1991, Specification for flame supervision devices for gas-burning appliances Thermoelectric types. BS EN 126:1995, Multifunctional controls for gas burning appliances. BS EN 161:1991, Automatic shut-off valves for gas burners and gas appliances. BS EN 257:1995, Mechan
26、ical thermostats for gas burning appliances. BS EN 298:1994, Automatic gas burner control systems for gas burners and gas-burning appliances with or without fans. BS EN 437:1997, Specification for test gases, test pressures and categories of appliances, for gas appliances. BS EN 484:1998, Specificat
27、ion for dedicated liquified petroleum gas appliances Independent hotplates, including those incorporating a grill for outdoor use. BS EN 50165:1997, Electrical equipment of non-electric appliances for household and similar proposes Safety requirements. BS EN 60730-2-9:2002, Specification for automat
28、ic electrical controls for household and similar use Particular requirements Particular requirements for temperature sensing controls. IEC 817:1984, Spring operated impact test apparatus and its calibration. ISO 7-1:1995, Pipe threads where pressure-tight joints are made on the threads Part 1: Dimen
29、sions, tolerances and designation. ISO 228-1:2000, Pipe threads where pressure-tight joints are not made on the threads Part 1: Dimensions, tolerances and designation. ISO 228-2:1987, Pipe threads where pressure-tight joints are not made on the threads Part 2: Verification by means of limit gauges.
30、ISO 274:1975, Copper tubes of circulation section Dimensions. ISO 7005-1:1992, Metallic flanges Part 1: Steel flanges. ISO 7005-2:1998, Metallic flanges Part 2: Cast iron flanges ISO 7005-3:1998, Metallic flanges Part 3: Copper alloy and composite flanges.BS 7977-2:2003 2 BSI 13 June 2003 3 Terms an
31、d Definitions For the purposes of this standard the following definitions together with those of BS 1179, apply. 3.1 Appliance and parts 3.1.1 appliance a combination of a back boiler and a gas fire 3.1.2 back boiler a water heating unit designed to fit into a builders opening to provide central hea
32、ting or central heating and domestic hot water 3.1.3 gas fire that part of the appliance that has a function similar to those within the scope of BS EN 509:2000 or BS 7977-1:2002 3.1.4 closed fronted gas fire a gas fire which does not have exposed flames or exposed incandescent areas 3.1.5 live fuel
33、 effect fire (LFE) gas fired appliance designed to heat a room mainly by the emission of air heated by convection. Such an appliance also contains radiant elements designed to simulate a solid fuel fire bed. It is designed to be mounted on a hearth, floor or wall 3.1.6 back circulator 1) a water hea
34、ter unit designed to fit into a fireplace recess intended primarily for the supply of domestic hot water in conjunction with a separate storage vessel and for operation by gravity circulation with a rated heat input not exceeding 7.2 kW net 3.2 Parts of the appliance conveying gas to the burners 3.2
35、.1 gas circuit the parts of the appliance conveying gas to the burners 3.2.2 inlet connection the part of the appliance intended to be connected to the gas supply 3.2.3 mechanical joint (mechanical means of obtaining soundness) a means of assuring the soundness of an assembly of several (generally m
36、etallic) parts without the use of liquids, pastes, tapes, etc. There are, for example: metal to metal joints; conical joints; toroidal sealing rings; flat joints 3.2.4 restrictor device with an orifice, which is placed in the gas circuit so as to create a pressure drop and thus reduce the gas pressu
37、re at the burner to a predetermined value for a given supply pressure and rate 1) Back circulators are not covered by this standard.BS 7977-2:2003 BSI 13 June 2003 3 3.2.5 sgas rate adjuster component allowing the gas rate of the burner to be brought to a predetermined value according to the supply
38、conditions. the adjustment may be progressive (screw adjuster) or discontinuous (changing restrictors). the adjuster of an adjustable governor is regarded as a gas rate adjuster. if, after the manufacturer or installer has adjusted an adjuster it is immobilized in this position by some means such as
39、 a screw, etc., it is said that the adjuster is “set” in this position 3.2.6 sealing an adjuster procedure by which after setting an adjuster, material is added such that any attempt to alter the setting is apparent factory sealed preset adjuster, other than the adjuster of a pressure governor, is c
40、onsidered to be non-existent. a pressure governor is considered to be non-existent if it has been factory sealed such that it cannot function as a pressure governor. 3.2.7 putting an adjuster or a control out of service adjuster or a control (of temperature, pressure, etc.) is said to be “put out of
41、 action” if it is sealed in a position such that the appliance then functions as if the device had been removed 3.2.8 gas rate control 2) component allowing the user to open, close or adjust the gas supply to one or more burners 3.2.9 range-rating device component on the appliance intended to be use
42、d by the installer to adjust the nominal heat input of the appliance, within the range of maximum and minimum heat inputs stated by the manufacturer, to suit the actual heat requirements of the installation 3.2.10 injector component that admits the gas into a burner 3.3 The burner 3.3.1 main burner
43、burner that is intended to assure the thermal function of the appliance and is generally called the burner 3.3.2 fuel effect burner burner that simulates a solid fuel flame. The flames pass through a simulated solid fuel bed 3.3.3 ignition device any means (flame, electrical ignition device or other
44、 device) used to ignite the gas at an ignition burner or main burner 3.3.4 ignition burner a small burner whose flame is intended to ignite a main burner 2) This device may be a “Tap”.BS 7977-2:2003 4 BSI 13 June 2003 3.3.5 ignition safety time time that elapses between the order to open the gas sup
45、ply to the burner and the gas supply being shut off in the event that no flame has been detected 3.3.6 extinction safety time time that elapses between extinction of the supervised flame and the order to shut off the gas supply to the burner 3.3.7 fixed primary aeration restrictor device containing
46、a restriction of fixed cross-section which limits the supply of air to a burner 3.3.8 non-volatile lockout shutdown condition such that a start can only be accomplished by a manual reset 3.3.9 volatile lockout shutdown condition such that a start can only be accomplished by restoration of the electr
47、ical supply after its loss 3.3.10 de-energized to trip principle principle according to which neither auxiliary energy nor external action is required to activate a safety device 3.4 Burner control systems 3.4.1 manually operated burner control system control system for an appliance in which manual
48、intervention by the user is necessary to turn on the appliance; to ignite the ignition burner, if any, and the main burner; to vary the heat input of the main burner and to shut off the appliance 3.4.2 semi-automatic burner control system control system for an appliance in which manual intervention
49、by the user is necessary to turn and ignite a permanent ignition burner. Ignition, from this ignition burner, control and extinction of the main burner is carried out automatically without the need for manual intervention 3.4.3 automatic control system system comprising at least a programming unit and all the elements of a flame detector device. The various functions of an automatic burner control syst
