User Manual

4
To use the gas ballast feature...
 MoisturefromtheA/C-Rsystemthatiscarriedintothepumpasavapor
tendstocondenseintoaliquidandcombinewiththevacuumpumpoil.
Whenmoisturecontaminatesthepumpoil,itreducesthepump’sability
toreachitsultimatedeepvacuumlevel.
 Thegasballastvalvepurgesasmallamountofatmosphericairthrough
theexhaustchamber.Thisextravolumeofairmixeswiththevapor
fromtherefrigerantsystemtopreventcondensationandtohelpexhaust
moistureintheformofvaporfromthepump.
 Thegasballastvalveislocatedbesidethehandle,oppositetheinlet
tting.Tousethegasballast,startthepumpandopenthegasballast
valveuntilthesystemhasreached1000–3000microns.Closethevalve
toallowthepumptopulldowntoitsultimatevacuumlevel.
 Thegasballastvalvemaybeopenedorclosedatanytimeduringpump
operation.Itisfullyopenattwoturnscounterclockwise.
 Note:Robinairrecommendstheuseofathermistorvacuumgaugeto
mostaccuratelymeasurevacuumlevels.
To shut down the pump after use...
 Tohelpprolongpumplifeandpromoteeasystarting,followthese
proceduresforshutdown:
 1.Closethemanifoldvalvebetweenthepumpandthesystem.
 2.TurntheIso-Valve™totheCLOSEDposition.
 3.Removethehosefromthepumpinlet.
 4.TurnthepumppowerswitchtoOFF.ReturntheIso-Valve™tothe
OPENpositionforafewsecondstorelieveanyvacuuminsidethepump.
 5.Captheinletporttopreventanycontaminationorlooseparticlesfrom
enteringtheport.