12Installation and ServicingSECTION 1 - GENERAL1.8 GAS SUPPLYThe local gas supplier should be consulted, at the installationplanning stage, in order to establish the availability of an adequatesupply of gas. An existing service pipe must NOT be used withoutprior consultation with the local gas supplier.The boiler MUST be installed on a gas supply with a governedmeter only.A gas meter can only be connected by the local gas supplier orby a Gas Safe Registered Engineer. In IE by a Registered GasInstaller (RGII).An existing meter should be checked, preferably by the gassupplier, to ensure that the meter is adequate to deal with the rateof gas supply required.It is the responsibility of the Gas Installer to size the gasinstallation pipework in accordance with BS6891:2005. Whilstthe principle of the 1:1 gas valve ensures the Logic range isable to deliver its full output at inlet pressures as low as 14mb,other gas appliances in the property may not be as tolerant.When operating pressures are found to be below the minimummeter outlet of 19mb these should be checked to ensure this isadequate for correct and safe operation.Allowing for the acceptable pressure loss of 1mb across theinstallation pipework, it can be assumed that a minimum permittedoperating pressure of 18mb will be delivered to the inlet ofthe appliance. (Reference BS 6400-1 Clause 6.2 PressureAbsorption).The external gas cock could further reduce the operating pressurewhen measured at its test point. The pressure drop is relative tothe heat input to the boiler (kW), refer to graph below.00.511.522.530 10 20 30 40 50Pressure drop (mbar )Heat Input to Boiler (kW)Gas Cock Pressure DropIMPORTANT.Ensure all gas valve connections are gas tight with a gassoundness check up to the gas control valve.Installation pipes must be fitted in accordance with BS.6891. In IErefer to IS.813:2002.The complete installation MUST be tested for gas tightness andpurged as described in the above code.1.9 FLUE INSTALLATIONPluming will occur at the terminal so terminal positions where thiscould cause a nuisance should be avoided.The flue must be installed in accordance with therecommendations of BS. 5440-1: 2008.In IE refer to I.S. 813:2002.The following notes are intended for general guidance:1. The boiler MUST be installed so that the terminal is exposedto external air.2. It is important that the position of the terminal allows the freepassage of air across it at all times.3. Minimum acceptable spacing from the terminal to obstructionsand ventilation openings are specified in Table 3.* Only one reduction down to 25mm is allowable per installationotherwise BS5440-1 2008 dimensions must be followed.Flue Terminal Positions Min. Spacing*1. Directly below, above or alongside an openingwindow, air vent or other ventilation opening. 300mm2. Below guttering, drain pipes or soil pipes. 25mm*BS5440-1 2008 75mm3. Below eaves. 25mm*BS5440-1 2008 200mm4. Below balconies or a car port roof. 25mm*BS5440-1 2008 200mm5. From vertical drain pipes or soil pipes. 25mm*BS5440-1 2008 150mm6. From an internal or external corner or to a 25mm*boundary alongside the terminal. BS5440-1 2008 300mm7. Above adjacent ground, roof or balcony level. 300mm8. From a surface or a boundary facing the terminal. 600mm9. From a terminal facing a terminal. 1,200mm10. From an opening in a car port(e.g. door or window) into dwelling. 1,200mm11. Vertically from a terminal on the same wall. 1,500mm12. Horizontally from a terminal on the wall. 300mmVertical Terminals13. Above the roof pitch with roof slope of all angles. 300mmAbove flat roof. 300mm14. From a single wall face. 300mmFrom corner walls. 300mm15. Below velux window 2000mm16. Above or side of velux window 600mmTable 3 - Balanced Flue Terminal Position4. Where the lowest part of the terminal is fitted less than 2m(6’6”) above a balcony, above ground or above a flat roofto which people have access then the terminal MUST beprotected by a purpose designed guard.Terminal guards are available from boiler suppliers. (Ask forTFC flue guard model no. K6 - round, plastic coated). In caseof difficulty contact:TFC Group Ltd. Tel. + 44 (0) 01732 351 680Tower House, Vale Rise Fax. + 44 (0) 01732 354 445Tonbridge. Kent TN9 1TB www.tfc-group.co.ukEnsure that the guard is fitted centrally.5. The flue assembly shall be so placed or shielded as to preventignition or damage to any part of any building.6. The air inlet/products outlet duct and the terminal of the boilerMUST NOT be closer than 25mm (1”) to combustible material.Detailed recommendations on the protection of combustiblematerial are given in BS. 5440-1:2008.IMPORTANT. It is essential to ensure, in practice, that productsof combustion discharging from the terminal cannot re-enter thebuilding or buildings through any openings into the building suchas ventilators, windows, doors, or other sources of natural airinfiltration, such as forced ventilation openings etc.If products of combustion re-entry is identified or suspected thisshould be immediately investigated and corrected following theguidance provided in the current Gas Industry Unsafe SituationProcedure.