Dunkirk PVSB - Maintaining Your Boiler; Low Water Cut-Off; Foaming, Priming or Surging; Burners

Checkthewaterleveleverydayortwo.Verifythewaterlineshownby
operatingthedrainvalveonthegauge.BESURETOPANDBOTTOM
VALVESONGAUGEAREALWAYSOPENSOTHATACTUALWATERLEVEL
WILLBESHOWNATALLTIMES.
Thegaugeglassshouldbedryabovethewaterline.Thewaterlineshould
notbouncemorethanaboutoneinchwhentheboilerissteaming.If
youseewaterdropletscarryingoverthroughthetopofthegaugeglass,
orexcessivebouncingofthewaterline,theboilerneedstobecleaned.
Followtheinstructionsunder"CleaningYourBoiler."
POP SAFETY VALVE
Beforetesting,makecertaindischargepipeisproperlyconnectedto valve
outletandarrangedto containandsafelydisposeol boilerdischarge.
Undernormaloperatingconditionsa "try levertest"mustbeperlormed
everymonth.A "try levertest" mustalso beperformedatthe endof
anynon-serviceperiod.Testatnormalsystemoperatingpressurebyholding
thetestleverfullyopenforatleastfivesecondsto flushthevalveseat
free of sedimentanddebris.Thenreleaseleverandpermitthe valve
to snapshut.II lift leverdoesnotactivate,or thereis no evidenceol
discharge,turn offboilerimmediatelyandcontacta licensedcontractor
orqualifiedservicepersonnel.
LOW WATER CUT-OFF
TheLowWaterCut-Offwill interruptthe electricalcurrentto theburner
whenthewaterlineintheboilerdropstoa lowlevel.
Onfloattypelowwatercut-offs,it is very importantto keepthefloat
chamberfreefromsediment,a conditionessentialto dependabilityTo
keepanyaccumulationfrominterferingwithfloatactionisto "BLOWDOWN"
orflushoutthecontrolregularlyThismustbedonetwoto threetimes
duringthefirstweekafterinstallationandoncea weekthereafterduring
theheatingseason.Doit whiletheboileris in operation.Firstnotewater
levelin gaugeglass.Openblow-offvalveat bottomof control;water
will pourout,flushingawaysediment.Drainuntilwateris clear,about
a pailful,thenclosevalve.If waterlevel in gaugeglasshasdropped,
addwatertoboilerto restorelevel.Consultlowwatercut-offmanufacturer's
instructionsincludedwithboiler.
NOTE: Openingblow-offvalvecheckscut-offoperationtoo.Asfloat
dropswithfallingwaterlevel,burnerswill shutoff.Aftervalveisclosed
andnormaloperatingconditionsarerestored,burnerswillresumefiring.
ForprobetypeLowWaterCut-Offs,checkactionof theLowWaterCut-
Offmonthlytomakesureitisprovidingtheproperprotection.See"Checking
andAdjusting"onpage19.LowWaterCut-Oflremoteprobesmustbe
removedforperiodicinspectionandcleaning,preferablyatthebeginning
ofeachheatingseason.Morefrequentcleaningmayberequiredonboilers
requiringconstantorveryfrequentadditionsofmakeupwater.
BURNERS
A visualcheckof thepilotandmainburnerflamesshouldbe madeat
leastonceeachyear,preferablyat thebeginningof theheatingseason.
Seepage19.
BOILER FLUE PASSAGES
Undernormaloperatingconditions,withthe burnersproperlyadjusted,
itshouldnotbenecessaryto cleantheboilerfluegaspassages,However,
to assuretrouble-freeoperation,werecommendthatyouhavetheflue
passages,burneradjustment,andoperationofthecontrolscheckedonce
eachyearbyacompetentServiceTechnician.
Beforethestartofeachseason(orwheneversystemhasbeenshutdown
for sometime)recheckthewholesystemfor leaks... andrecheckthe
boilerandventpipeforleaks.
VENT PIPE
Theventingol thisunitis veryimportantandthepipingshouldbechecked
at leastoncea season.If the ventpipingshowsany signof leaking,
replaceit immediately
CLEANING YOUR BOILER FLUE PASSAGES
AND BURNERS
FluePassagesbetweensectionsshouldbe examinedyearlyandcleaned,
il necessaryToclean,removeburners,pilot,andventpipe.Removetop
andfrontjacketpanels.Removethetwoscrewsattachingtheintermediate
front panelto the left andright sidejacketpanels.Removethe draft
diverterandintermediatefrontpanelasaunit.Carefullyremovethecerafelt
gasketstrips.Cleanpassagewaysbetweensectionswithaflexiblehandle
wirebrush.Removedirtfrombottomol boilerandfrombetweensections
by vacuuming.Makesureall flameportsin burnersareopenandclear.
Shakeoutor blowout all loosedirt in burners.Resealseamsbetween
adjacentsectionsasnecessarywith400FRTVsiliconesealant.Reassemble
all parts.Besureto checktightnessof pilotconnectionsandcondition
ofburnerflamesafterreassembly(seeFigures18and19).Besurevent
pipeconnectionstochimneyaresecureandnoobstructionsarepresent.
FOAMING, PRIMING OR SURGING
Thesetermsareusedto describea fluctuatingwaterline- whenwater
leavestheboilerwiththesteam.
Itiscausedbyanycombinationof thefollowing:
1. Threadingoil andorganicmatterin the boilerwater.(Mineraloil,or
coresanddoesnotcausesurging.)Followinstructionsunder"Cleaning
YourBoiler."
2. Faultyquickventsthatdo not releaseair untila sizeablepressure
is builtup- if oldstyle,replace- if dirty cleansoyoucaneasily
blowthroughvalve.
3. Improperheaderdesign- whensteamflowsin oppositedirection
of equalizerlineon "HartfordLoop."Generallya 15"horizontalrun
betweenriserandmaintakeoffwill allowentrainedwaterto fall out
of thesteamvaporso it can returnto boiler.(SeeFigures5, 6A
&6Bonpages5 and6).
4. Adjustmentofsteamtimitcontrolto awidedifferentialincreasesdifliculty
if quickventsareoldstyle,slow-releasingtypeor dirty Alwaysset
steamlimitcontroldifferentialaslowaspossible.
5. Soapanddetergentsintheboilerwatercauseextremesurging.Boiler
cleanersandchemicalcleaningadditivesarenotrecommended.Ifused
andnotrinsedproperlytheywilldomoreharmthangood.Thecleaning
procedureslaid out in theseinstructionswill cleanoutthe typical
oilsandimpuritiesfoundinnewboilersandinresidentialheatingsystems.
Thebestthingforyourboilerandheatingsystemis cleanwaterwith
noadditives.
CAUTION
Never refill a hot boiler with cold water - the danger
of thermal shock may crack a section.
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BOILER WATER TREATMENT (Other Than Cleaners)
in steamsystemswherethe systemis tight,free from leaks,andall
thesteamis returnedto theboileras condensate,theamountof make
upwaterissmall.Watertreatmentisgenerallynotrequired.
In steamsystemswithlessthan90% of the steambeingreturnedas
condensate,orwithveryhardor corrosivemakeupwater,treatmentmay
bedesirable.Followtherecommendationsofyourlocalboilerwatertreatment
specialist.
BETWEEN HEATING SEASONS
Boilersshouldnotbedrainedbetweenheatingseasons.Steamboilersshould
beentirelylilledwithwaterduringthesummermonthsto excludeair.
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