Hitachi UTOPIA R32 Series - Insulation

9 Piping work and refrigerant charge
Copper pipes, sizes and connection
TCGB0136 rev.1 - 05/2021
91
9
? NOTE
• Donotusesaws,grindstoneorothertoolswhichmightcreatecopperdust.
• Whencuttingpipes,securetheparttobesolderedasshownintheServiceManual.
• Strictlyfollownationalorlocalregulationsregardingoccupationalhealthandsafety.
• Wearappropriatemeansofprotectionduringcuttingorbrazingoperationsandinstallation(gloves,eyeprotection,etc).
? NOTE
• Asystemwithnomoistureoroilcontaminationwillgivemaximumperformanceandlife-cycleascomparedwithapoorlyprepared
system.Takeparticularcaretoensurethatallcopperpipingiscleananddryinternally.
• Toensurethis,blowoxygenfreenitrogenthroughthepipes.
! CAUTION
• Captheendofthepipewhenthepipeistobeinsertedthroughahole.
• Donotplacepipesdirectlyonthegroundwithoutacaporvinyltapecoveringtheend,asitshowninthegure.
Right Wrong
• Ifpipinginstallationcannotbecompleteduntilthefollowingdayorlonger,soldertheendsofthepipingtoclosethemandloadwith
oxygen-freenitrogenusinganaccessdevicesuchasaSchradervalvetoavoidmoistureandcontaminationbyextraneousparticles.
• DonotuseinsulationmaterialcontainingNH3asitcandamagethecopperpipingmaterialandmaybeasourceoffutureleakage.
9.3.2 Insulation
Attach insulation to Multikit branch (eld-supplied or package with each one depending on model) using vinyl tape. Also
attach insulation to eld-supplied piping to prevent capacity decrease due to ambient air conditions and dewing on pipe
surface caused by low pressure.
? NOTE
Whenpolyethylenefoamisapplied,athicknessof10mmfortheliquidpipingandfrom15mmto20mmforthegaspipingisrecommended.
! CAUTION
Performinsulationworkafterthesurfacetemperaturedecreasestotheroomtemperature,Ifnot,theinsulationmaterialmaymelt.Ifthe
endsofthepipingsystemareopenafternishingtheinstallationwork,securelyattachcapsorvinylbagstotheendsofthepipingto
preventmoistureordustentering.