Gas Supplies 704C ignition temperature Stages of the

Gas Supplies 704°C ignition temperature Stages of the combustion process Note: nitrogen is also present within the atmosphere but plays no part in the combustion process and therefore can be ignored outer mantle 5– 15% gas in air Fuel (methane) Stage 1: requirements for combustion to occur reaction zone Stage 2: the oxidation of the fuel within the appliance secondary air supply unburnt gas/air mixture primary air drawn in gas injector carbon dioxide water vapour gas supply The operation of an aerated burner Properties and combustion of natural gas Copyright Blackwell Publishing Ltd, all rights reserved: www. blackwellpublishing. com From Plumbing (3 rd edition), R. D. Treloar, page 191 Final stage: products passing out through the flue pipe

Gas Supplies existing flue 10 mm 2 cable Regulation No. 8 The construction of the dormer window will affect the effective discharge of flue gases from the building unless the terminal is raised Regulation No. 10 Temporary bonding wire required when removing a section of pipework pipe sleeve proposed dormer within 1. 5 m mastic seal to one side of sleeve only Regulation No. 30 Open flued appliances are not permitted to be installed in bathrooms screwdriver Regulation No. 19 Pipes must be sleeved when passing through a wall cavity dust cap gas regulator inlet gas supply From Plumbing (3 rd edition), R. D. Treloar, page 193 Copyright Blackwell Publishing Ltd, all rights reserved: www. blackwellpublishing. com Regulation No. 33 Burner pressure to be adjusted in accordance with manufacturer’s instructions to gas burner Gas safety regulations

Gas Supplies meter regulator gas meter pipe capped off GRP protective sleeve high level vent meter control valve Semi-concealed meter box 375 mm min dpc. 0. 5 m min 1. 0 m max PE service pipe Surface mounted meter box expansion joint in vertical section Sleeve sealed internally sleeve riser low level vent Sunken meter box Gas supply to the consumer From Plumbing (3 rd edition), R. D. Treloar, page 195 Copyright Blackwell Publishing Ltd, all rights reserved: www. blackwellpublishing. com 1/2 hour fire resistant access panel incoming steel base plate to support weight of riser gas supply Internal riser

Gas Supplies cooker 14. 6 k. W boiler 17 k. W gas meter D 1. 5 m E 2. 0 m 0. 6 m A C 4. 0 m 3. 0 m 0. 6 m B 3. 0 m fire 5 k. W Sizing of gas pipework From Plumbing (3 rd edition), R. D. Treloar, page 197 Copyright Blackwell Publishing Ltd, all rights reserved: www. blackwellpublishing. com

Gas Supplies Gas meter with low pressure regulator meter bracket Gas meter with medium pressure regulator and test valve gas regulator Tightness testing gas carcass prior to meter installation test nipple clamping peg or plug cock consumer’s emergency control cock installation pipework test dial gas meter hand pump manometer incoming gas Tightness testing installation with supply gas meter fitted Tightness testing and purging From Plumbing (3 rd edition), R. D. Treloar, page 201 Copyright Blackwell Publishing Ltd, all rights reserved: www. blackwellpublishing. com

Gas Supplies turn clockwise to increase pressure dust cap pressure adjusting screw breather hole test nipple diaphragm gas inlet section through gas regulator gas burner manometer Typical multi-functional valve working pressure and standing pressure if all appliances are turned off burner pressure reading main solenoid valve button to operate thermoelectric valve Thermoelectric valve pilot flame thermocouple valve ‘X’ electromagnet regulator Gas regulator section through a multi-function gas valve Gas controls 1 From Plumbing (3 rd edition), R. D. Treloar, page 205 Copyright Blackwell Publishing Ltd, all rights reserved: www. blackwellpublishing. com

Gas Supplies rod type thermostat weep pipe Gas relay valve diaphragm bypass orifice diaphragm coil of wire iron plunger reset plunger Solenoid valve pilot flame Low pressure cut-off thermistor located in draught diverter Atmosphere sensing device spark electrode thermocouple pilot thermocouple primary air port Oxygen depletion sensor lack of oxygen at the flame primary air port causes the flame to alter, thus fails to impinge onto thermocouple causing the gas valve to close From Plumbing (3 rd edition), R. D. Treloar, page 207 Copyright Blackwell Publishing Ltd, all rights reserved: www. blackwellpublishing. com Gas controls 2 thermocouple interruptor

Gas Supplies two dissimilar metals bonded together Liquid vapour device bellows phial valve spring Bi-metallic strip bypass orifice reset button pilot tube A thermocouple Thermoelectric, liquid vapour and photo-electric flame supervision devices B C solenoid Thermoelectric valve ac current dc current Note: this illustration simplifies the concept of flame rectification. Thus, once a flame is established an electrical circuit is formed From Plumbing (3 rd edition), R. D. Treloar, page 209 Copyright Blackwell Publishing Ltd, all rights reserved: www. blackwellpublishing. com control box Flame rectification device Flame supervision devices solenoid

Gas Supplies hot gases exit at high level terminal hot gases rise due to convection currents flue pipe 25 mm secondary flue non-combustible sleeve to maintain fire precaution draught diverter primary flue cool air enters at low level down draught air vent required for appliances over 7 k. W 600 mm boiler casing draught diverter adverse conditions Draught diverter situated above a boiler diluent air drawn in (under normal conditions) diverter incorporated within appliance diverter fitted separate from appliance Open flued appliances From Plumbing (3 rd edition), R. D. Treloar, page 211 Copyright Blackwell Publishing Ltd, all rights reserved: www. blackwellpublishing. com

Gas Supplies high rise building wind direction Positive and negative pressure zones to be avoided for siting of flue terminals relying on natural flue draught Unless there is no wind this example will always be in a positive pressure zone irrespective of wind direction 600 mm 250 mm if less than 600 mm increase to above ridge location ridge terminal Typical gas flue terminals 0. 6 m parapet wall 600 mm 1. 5 m 0. 6 m greater than 1. 5 m within 1. 5 m Terminal location for open flues From Plumbing (3 rd edition), R. D. Treloar, page 213 Copyright Blackwell Publishing Ltd, all rights reserved: www. blackwellpublishing. com roof pitch

Gas Supplies chimney liner terminal flaunching clamping plate self tapping screw liner flue gases where single flue pipes with sockets are used the spigot should sit into the socket with the spigot uppermost register plate or glass fibre quilt twin wall flue pipe back boiler Installation of a flue liner A liner secured to boiler and the joint made sound with fire cement straight bonding block first floor section A–A ground floor fire recess starter block From Plumbing (3 rd edition), R. D. Treloar, page 215 A Installation of pre-cast concrete flue blocks Materials and construction of open flues Copyright Blackwell Publishing Ltd, all rights reserved: www. blackwellpublishing. com

Gas Supplies heat exchanger closure plate 50 mm min radiants Traditional gas fire 250 mm minimum debris collection space flue way heat exchanger hearth Inset live effect fire back Decorative fuel effect fire From Plumbing (3 rd edition), R. D. Treloar, page 217 Installation of gas fires Copyright Blackwell Publishing Ltd, all rights reserved: www. blackwellpublishing. com

Gas Supplies angled bayonet socket looking down cooker hose cooker stability bracket 610 mm 150 mm 760 300 mm mm 50 mm minimum dimensions to be observed 20 mm From Plumbing (3 rd edition), R. D. Treloar, page 219 Copyright Blackwell Publishing Ltd, all rights reserved: www. blackwellpublishing. com Gas cooker installation 20 mm

Gas Supplies combustion products air inlet burner Natural draught appliance Room sealed boiler This design would no longer meet current legislation fan heat exchanger Fan assisted appliance Natural draught terminal Note: a guard is required where the terminal is accessible (i. e. < 2 m from an accessible area) Room sealed appliances 1 From Plumbing (3 rd edition), R. D. Treloar, page 221 Copyright Blackwell Publishing Ltd, all rights reserved: www. blackwellpublishing. com Fan assisted terminal

Gas Supplies flue gases out air intake concentric flue/air duct parallel flue/air ducts (allows for greater flue length) flue gas extract Vertical room sealed appliances 150 mm maximum air intake twin wall or insulated flue pipe self closing door which, when closed, allows the electrical supply to pass to the boiler open flued appliance Balanced compartment From Plumbing (3 rd edition), R. D. Treloar, page 223 Room sealed appliances 2 Copyright Blackwell Publishing Ltd, all rights reserved: www. blackwellpublishing. com

Gas Supplies W A H A section A–A Typical terracotta air vent L effective grille size: H x W x No. holes example: if the hole size was to measure 10 mm x 10 mm in the terracotta grille shown the effective free area would be 10 x 20 = 2000 mm 2 (20 cm 2) B B Typical sheet metal vent effective grille size: L x W x No. slots Typical ventilator grilles W section B–B where a grille is installed within a cavity wall it must be made to bridge the gap of the cavity Ventilation requirements From Plumbing (3 rd edition), R. D. Treloar, page 225 Copyright Blackwell Publishing Ltd, all rights reserved: www. blackwellpublishing. com

Gas Supplies flue gas outlet terminal 600 mm min 400 mm min terminal outlet secondary flue draught diverter main flue way air supply inlet appliance ‘Vertex’ or ‘Solver’ flue system primary flue Branched flued system appliance combustion products terminal Balanced flued appliances air inlet Se duct From Plumbing (3 rd edition), R. D. Treloar, page 227 Copyright Blackwell Publishing Ltd, all rights reserved: www. blackwellpublishing. com Other flueing systems U duct air inlet

Gas Supplies 3 m emergency control valve 1 st stage regulator (this distance may be reduced for small bulk tanks) 2 nd stage regulator and UPSO pressure relief valve float LPG bulk tank installation OPSO Bulk tank supply automatic changeover valve 1 m 0. 3 m 1 m 1 m UPSO OPSO valve From Plumbing (3 rd edition), R. D. Treloar, page 229 Copyright Blackwell Publishing Ltd, all rights reserved: www. blackwellpublishing. com minimum dimensions to be observed when siting LPG supply 2 m Cylinder supply drain

Gas Supplies automatic change over valve and regulator pigtail LPG cylinder emergency control valve Selection of LPG regulators pressure adjusting screw Regulator valve From Plumbing (3 rd edition), R. D. Treloar, page 231 LPG regulators Copyright Blackwell Publishing Ltd, all rights reserved: www. blackwellpublishing. com diaphragm

Gas Supplies hose bellows unit Gas analyser and remote printer sampling tube sampling probe plunger non-return valve ‘Draeger’ flue gas analyser sampling probe hand pump ‘Fyrite’ CO 2 analyser Combustion analysis From Plumbing (3 rd edition), R. D. Treloar, page 233 Copyright Blackwell Publishing Ltd, all rights reserved: www. blackwellpublishing. com

Gas Supplies draught diverter piece of copper tube used to make suitable smoke match holder (to prevent burning hands) issuing smoke match tube crushed close to provide suitable pocket flue pipe tube blocked off at end spillage occurring with a gas fire the smoke match is to be held along top edge of the radiants draught diverter no spillage indicated smoke match to be held at all edges of draught diverter Spillage testing open flued appliance From Plumbing (3 rd edition), R. D. Treloar, page 235 Copyright Blackwell Publishing Ltd, all rights reserved: www. blackwellpublishing. com Flue efficiency in gas appliances

Gas Supplies Handing over! Commissioning of gas installations From Plumbing (3 rd edition), R. D. Treloar, page 237 Copyright Blackwell Publishing Ltd, all rights reserved: www. blackwellpublishing. com

Gas Supplies From Plumbing (3 rd edition), R. D. Treloar, page 239 Copyright Blackwell Publishing Ltd, all rights reserved: www. blackwellpublishing. com

Gas Supplies Typical line diagram to be used showing all pipe runs and valves >28 mm in size lugs welded to pipe ‘U’-bolt support to hold the pipe firm clip designed to allow vertical free movement. The pipe simply sits onto the bracket, hanging freely ‘U’-bolt support allowing for expansion Pipe roller and chair designed to allow horizontal free movement From Plumbing (3 rd edition), R. D. Treloar, page 241 Copyright Blackwell Publishing Ltd, all rights reserved: www. blackwellpublishing. com

Gas Supplies Dealing with gas installations which do not comply with current Regulations and Standards From Plumbing (3 rd edition), R. D. Treloar, page 243 Copyright Blackwell Publishing Ltd, all rights reserved: www. blackwellpublishing. com