
Page11Precision‐24PumpChlorinationSystemInstallationGuideRev62416CleanWaterSystems2016
timehasoccurred.Afterthechlorinehascombinedwiththevarioussubstancessuchasbacteria,iron,manganeseand
odor,somelevelofuncombinedor“free”chlorinewillexist.Thegoalistohavesomesmallamountoffree‐chlorine,
usuallyaround0.2to0.4ppmoffree‐chlorine,uptoamaximumof1.0ppmoffree‐chlorine.
Forbacteriayouwanttoinject1–2ppmofchlorinewithapproximately10minutesofcontacttime.Ifthewateris
colderthan50F(10C)and/orthepHishigherthan7.5youmayneedlongercontacttimeorahigherresidual.Foreach
partpermillionofironormanganesegenerallyyouwanttoinject1ppmofchlorine.Foreach1.0ppmofhydrogen
sulfidegas(whichcausestherotteneggsmellinwater)youwanttoinject2to3ppmofchlorine.Sosayyouhave
bacteriaand2.0ppmofiron.Forourexamplehere,wewillassumeyouwanttoinject3ppmofchlorine.
StepThree:Determinewhatsolutionstrengthofbleachtouse
Householdbleachisapproximately5%chlorine;poolchlorineis10to12%.5%isthesameassaying50,000partsper
million(PPM)and10%isthesameassaying100,000PPM.
Regardingthesolutionstrength:Ifyoudilutethebleachbyusing3gallonsofpurewaterto1gallonofhousehold
bleach,youendupwithsolutionstrengthofapproximately1.25%or12,500ppm.Inotherwords,householdbleachhas
asolutionstrengthof50,000ppm,andifyoudiluteitwith3gallonofwater,youendupwithsolutionstrengthof12,500
ppm,whichisagoodsolutionstrengthtouseformosthomewellwaterapplicationswithwaterflowratesof5to20
gallonsperminute.Regardingsettingtheoutputofthemeteringpump:Youcanvarytheapplieddosageofchlorineby
adjustingthechlorinebleachsolutionstrengthandsettingthePrecision‐24PumpFeedRateStrokeDialuntilyou
achievethedesiredresidual.
FormulaforFindingtheSolutionStrengthandMeteringPumpSettings:
Theformulaissimple,youonlyhaveto:MultiplytheWellPumpFlowRate(ingallonsperminute)timestheApplied
ChlorineDosageinPartsPerMillionDesiredtimes1440.ThendividebytheSolutionStrengthinPPMthatisbeingused.
Example:Assumethatyouhaveawellpumpthathasaflowrateof12gallonsperminute(12GPM)andthatyouwant
toinject3.0ppmofchlorineintothewater.Youhavedecidedtouseasolutionstrengthof12,500ppmor1gallonof
5%bleachto3gallonsofpurifiedoratleastsoftenedwater.Thereare1440minutesin24hourperiod,andthe
formulawilltellyouhowmanygallonsofchlorineyouwilluseforevery24hoursthewellpumpruns.
Theformulais:12GPMx3.0PPMx1440andthendividedby12,500=4.14GallonsPerDay
Thismeansthatyouneedameteringpumpthathasanoutputof4gallonsperday.Themaximumoutputofyour
Precision‐24meteringpumpis24.0gallonsperday,butitcanbeeasilyadjustedtoputout4.0gallonsperday.This
meansifthePrecision‐24pumpweretorunfor24hours,itwouldpumpatotalof4.0gallons.
Forexample,bysettingthestrokeknobto70%andthespeedto25%wecanachievetheoutputneededof2.0gallons
perday.(24x0.7)x0.25=4.2gallonsperday.
Yourwellpumpmightrunfor1houraday,soatthisrateyouwoulduse4.0gallonsofyourchlorinebleachsolution
every24hoursthepumpruns.Itisbettertoaddmoresolutioneveryonetotwomonthsasthesolutioncanloseits
potencyovertime.
Whateveryourinitialsettingbesuretotestfortotalandfree‐chlorineandthen
adjustthepumpand/orthesolutionstrengthtoachieveyourdesiredfree‐
chlorineresidualinyourpiping.