Crown Bermuda Installation Manual

CAUTION

• INSTALLBOILERSOTHATTHEGASIGNITIONSYSTEMCOMPONENTSAREPROTECTED

 FROMWATER(DRIPPING,SPRAYING,RAIN,ETC.)DURINGAPPLIANCEOPERATIONANDSERVICE

 (CIRCULATORREPLACEMENT,ETC.).

• OPERATIONOFTHISBOILERINASYSTEMHAVINGSIGNIFICANTAMOUNTSOFDISSOLVED

 OXYGENCANCAUSESEVEREHEATEXCHANGERCORROSIONDAMAGE.

VIII System Piping

General Piping Notes

Figure11showsrecommendednearboilerpipingformostcommontypesofgravityreturnsteamsystems.Additional

informationonsteamsystemdesignmaybefoundinInstallation Guide for Residential Hydronic Heating Systems (Pub.

#200)publishedbytheHydronicsInstituteinBerkeleyHeightsNJ.

Oneoftheprimarypurposesofthisnearboilerpipingistoseparatetinywaterdropletsfromthesteamexitingtheboiler

sothat“dry”steamissenttothesystem.Ifthenearboilerpipingisnotcorrect,wetsteamwillenterthesystemandthe

followingproblemsmayoccur:

• Shortcyclingonlowwater

• BoilerorsystemFlooding

• Hammering

• Failuretoheatoneormoreradiators

AvoidthethreecommonpipingmistakesshowninFigure12.Thisapplieseveniftheexistingboilerhasoneofthepiping

mistakesshowninFigure12andappearstobeworking.Iftwoormoresteammainsmustbeconnectedtotheboiler,connect

aseparatetake-offforeachmainintotheheaderbetweentheriser(s)andequalizer.Alsonotethefollowingpoints:

1)Asizereductionmustbemadetoconnecttheheadertotheequalizer.Thisreductionmustbemadeintheequalizerline.

Donotmakethissizereductioninthehorizontalheader.

2)Onepipesteamsystemsrequireairventsoneachradiator,aswellasattheendofeachmain.Forthesystemtowork

properly,theseventsmustbeproperlyinstalled,sized,andbeingoodcondition.Inspectandreplaceanydefectivevents.If

therearenoventsattheendsofthemains,installthem.

3)DonotattempttomanifoldmultipleBSIswithgravityreturns.

4)Forinstallationswithcondensateorboilerfeedpumps,followthepumpmanufacturer’spipinginstructions.Suchsystems

generallydonotrequireHartfordloops.

5)Donotuseacheckvalveinplaceof,orinadditionto,aHartfordlooponagravityreturnsystem.

6)Pipethellconnectionfromacleansourceofcoldwater.Whenthewatersupplyisfromawell,makesurethatastrainer

isinstalledinthewellsystem.

7)PipingwithaChiller-Iftheboilerisusedinconjunctionwithachiller,pipetheboilerinparallelwithchiller.Use

isolationvalvestopreventchilledwaterfromenteringtheboiler.