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VIII Gas Piping
 Gaspipingtotheboilermustbesizedtodeliveradequategasfortheboilertoreatthenameplateinputatan
inletpressurebetweentheminimumandmaximumvaluesshownontheratingplate.Formoreinformationon
gaslinesizing,consulttheutilityortheNational Fuel Gas Code.
 Figure7.1showstypicalgaspipingconnectiontotheCHGboiler.Asedimenttrapmustbeinstalledupstream
ofallgascontrols.Installthefactoryprovidedmanualshut-offvalveoutsidethejacketwithagroundjoint
unionasshown.
 Theboileranditsgasconnectionmustbeleaktestedbeforeplacingtheboilerinoperation.Whendoingthis,
theboileranditsindividualshut-offmustbedisconnectedfromtherestofthesystemduringanypressure
testingofthatsystematpressuresinexcessof1/2psi.Whenpressuretestingthegassystematpressuresof
1/2psiorless,isolatetheboilerfromthegassupplysystembyclosingitsindividualmanualshut-offvalve.
Figure 7.1: Gas Connection To Boiler