Manual

Series 9DM2, 9DM3
Dual Check with Atmospheric Vent
Sizes:
1
⁄2",
3
⁄4" (15, 20mm)
Model 9DS- Remove union connections before sweating
•The9DDualCheckwithAtmosphericVentisdesignedforuseonnon-healthhazard,
continuouspressure,pointofuseapplicationsforprotectionagainstbacksiphonage
andbackpressure.Installinaccordancewiththelocalcodes.
•Forthebestsystemperformance,installonthefreshwaterfeedlinebeforeanypres-
sureregulators(suchastheWattsSeries1156onaresidentialboilerapplication).
•Flushthelinebeforeinstallingtheunittoremoveanysolder,fluxorpipechips.Clean
thestrainereverysixmonthsorasconditionsrequire.
•Somedischargeisexpected,particularlyonstart-up,untilallseatingsurfacesseal.
Continuousdischargeisanindicationthattheinternalseatingpartsandsurfacesmay
requirethecleaning.
•Maybeinstalledhorizontallyorvertically.
•Quickclosingvalves,waterhammerorsupplypressurefluctuationscancauseinter-
mittentdischarge.TheinstallationofaWaterHammerArrestors(WattsSeries05)or
WaterPressureRegulator(WattsSeries1156or25AUB)mayberequiredtocorrect
theproblem.

NOTICE
Itisimportantnottoinstallwherethe
dischargecouldcausedamage.Pipe
thedischargelineinaccordancewith
localcoderequirements.Aphysicalair
gapmustbemaintainedbetweenthe
dischargepipeandthedrainorsump.
Createtheairgapbycuttingthepipe
ona45°bevel,atadistanceof12"
abovethefloor.Ifusedonboilerappli-
cationsdonotuseanairgapfitting
atfacelevelsoastopreventpersonal
injuryfromscaldingwaterorsteam.In
noeventshouldtheventopeningordrainlinebeplugged.
•Iflocalcodesrequirethedevicebetested,itmustbeinstalledasshownin
thedrawingonthereverseside.
RP/IS-9D
9D Total Repair Kits
EDP NO. KIT NO. SIZE
0886010 RK 9DM2 T
1
⁄2",
3
⁄4" (15, 20mm)
0886011 RK 9DM3T
1
⁄2" (15mm)
Kit includes: primary & secondary checks, seat
and two union seals.
Boiler Installation
Watts 9DM3 Heating System Installation
Supply
Boiler
Return
Vent
Drain
Floor Drain
Integral
Strainer
Watts Model 1156F Feed
Valve with Union
Watts
9DM3
WARNING
!
Read this Manual BEFORE using this equipment.
Failure to read and follow all safety and use information can
result in death, serious personal injury, property damage, or
damage to the equipment.
Keep this Manual for future reference.
NOTICE
InquirewithGoverningAuthoritiesforLocal
InstallationRequirements
NOTICE