Daikin Enfinity VFC - Piping

unit installation
IM 930-6 •EnnityVerticalWaterSourceHeatPumps 10 www.DaikinApplied.com
Piping
1. Allunitsshouldbeconnectedtosupplyandreturn
pipinginatwo-pipereversereturnconguration.A
reversereturnsystemisinherentlyself-balancing
andrequiresonlytrimbalancingwheremultiple
quantitiesofunitswithdifferentowandpressuredrop
characteristicsexistinthesameloop.Checkforproper
waterbalancebymeasuringdifferentialtemperature
readingacrossthewaterconnections.Forproper
waterow,thedifferentialtemperatureshouldbe12°F
to14°F(5°Cto8°C)forunitsincoolingmode.
Adirectreturnsystemmayalsowork,butproperwater
owbalancingismoredifculttoachieveandmaintain.
2. Thepipingcanbesteel,copperorPVC.
Note: If using PVC (schedule-40) construction grade
pipe or better, use the manufacturers recom-
mended high temperature adhesive. With PVC
piping the appropriate number of hanger brackets
must be used to help prevent sagging.
3. Supplyandreturnrunoutsusuallyjointheunitviashort
lengthsofhighpressureexiblehosewhicharesound
attenuatorsforbothunitoperatingnoiseandhydraulic
pumpingnoise.Oneendofthehoseshouldhave
aswivelttingtofacilitateremovalforservice.Hard
pipingalsocanbebroughtdirectlytotheunit.This
optionisnotrecommendedsincenovibrationornoise
attenuationcanbeaccomplished.Thehardpiping
musthaveunionstofacilitateunitremoval.SeeFigure
8,Figure9,andFigure10fortypicalpipingdetails.
Figure 8: Typical Vertical Unit Piping
4. Someexiblehosethreadedttingsaresuppliedwith
sealantcompound.Ifnot,applyTeontapeforatightseal.
5. Supplyandreturnshutoffvalvesarerequiredat
eachunit.Thereturnvalveisusedforbalancingand
shouldhavea“memorystop”sothatitcanalways
beclosedoffbutcanonlybereopenedtotheproper
positionfortheowrequired.
6. Donotconnectanyunittothesupplyandreturnpiping
untilthewatersystemhasbeencleanedandushed
completely.Afterthecleaningandushinghastaken
place,theinitialconnectionshouldhaveallvalveswide
openinpreparationforwatersystemushing(see
"Cleaning&FlushingWaterSystem"onpage8).
7. Condensatepipingcanbesteel,copperorPVC.
Eachunitincludesacondensateconnection.
8. Unitsareinternallytrapped.
9. Donotlocateanypointinthedrainsystemabove
thedrainconnectionofanyunit.
10. Automaticowcontrolleddevicesmustnotbe
installedpriortosystemcleaningandushing.
11. Ahighpointofthepipingsystemmustbevented.
12. Checklocalcodefortheneedfordielectricttings.
Note: Do not over-torque ttings. The maximum torque
without damage to ttings is 30 foot pounds. If a
torque wrench is not available, use as a rule of
thumb, nger-tight plus one quarter turn.
Figure 9: Typical Vertical Installation and Unit Piping
1 SupplyAirDucting
2 AcousticalThermalLining(10ft.)
3 LineVoltage-7/8"(22mm)Hole
4 LowVoltage-7/8"(22mm)Hole
5 FlexibleDuctCollar
6 LouveredDoorforReturnAir
7 CondensateDrainConnection
8 FlexibleReturnHosewithFlowController/BallValve(3/4"FPT)
9 FlexibleSupplyHosewithY-Strainer/BallValve(3/4"FPT)
10 AccessPaneltoController
11 LEDAnnunciatorStatusLights
12 VibrationIsolationPad