12
ENVISION RESIDENTIAL INSTALLATION MANUAL
Plumbing Installation
1. Inspectthediptubeinthewaterheatercoldinletforacheckvalve.Ifacheckvalveispresentitmustberemoved
or damage to the desuperheater circulator will occur.
2. Removedrainvalveandtting.
3. Threadthe3/4-inchNPTx3-1/2-inchbrassnippleintothewaterheaterdrainport.
4. Attachthecenterportofthe3/4-inchFPTteetotheoppositeendofthebrassnipple.
5. Attachthe1/2-inchcopperto3/4-inchNPTadaptortothesideoftheteeclosesttotheunit.
6. Installthedrainvalveontheteeoppositetheadaptor.
7. RuninterconnectingtubingfromtheteetoDHWwaterout.
8. Cutthecoldwater“IN”linegoingtothewaterheater.
9. Insertthereducingsolderteeinlinewithcoldwater“IN”lineasshown.
10. RuninterconnectingcoppertubingbetweentheunitDHWwater“IN”andthetee(1/2-inchnominal).
Therecommendedmaximumdistanceis50feet.
11. Topreventairentrapmentinthesystem,installaventcouplingatthehighestpointoftheinterconnectinglines.
12. Insulateallexposedsurfacesofbothconnectingwaterlineswith3/8-inchwallclosedcellinsulation.
Note: All plumbing and piping connections must comply with local plumbing codes
.
Desuperheater Startup
1. Closethedrainvalvetothewaterheater.
2. Openthecoldwatersupplytothetank.
3. Open a hot water faucet in the building to bleed air from the system. Close when full.
4. Openthepressurereliefvalvetobleedanyremainingairfromthetank,thenclose.
5. Ifsoequipped,unscrewtheindicatorplug1turnonthemotorendofthepumpuntilallairispurgedfromthepump,
then tighten the plug. Use vent couplings to bleed air from the lines.
6. Carefullyinspectallplumbingforwaterleaksandcorrectasrequired.
7. Beforerestoringelectricalsupplytothewaterheater,adjustthetemperaturesettingonthetank.
• Ontankswithbothupperandlowerelements,thelowerelementshouldbeturneddowntothelowestsetting,
approximately100°F.Theupperelementshouldbeadjustedto120°Fto130°F.Dependinguponthespecic
needs of the customer, you may want to adjust the upper element differently.
• Ontankswithasingleelement,lowerthethermostatsettingto120°F.
8. Afterthethermostat(s)isadjusted,replacetheaccesscoverandrestoreelectricalsupplytothewaterheater.
9. Makesurethatanyvalvesinthedesuperheaterwatercirculatingcircuitareopen.
10. Turnontheunittorststageheating.
11. TheDHWpumpshouldberunning.Whenthepumpisrststarted,opentheinspectionport1turn(ifequipped)until
waterdribblesout,thenreplace.Allowthepumptorunforatleastveminutestoensurethatwaterhaslledthe
circulatorproperly.BesuretheswitchfortheDHWpump(SW4)is“ON”.TheDHW“OFF”LEDontheunitshouldnot
be illuminated.
12. Thetemperaturedifferencebetweenthewaterenteringandleavingthedesuperheatershouldbe5°Fto15°F.The
waterowshouldbeapproximately0.4GPMpertonofnominalcooling.
13. Allowtheunittoheatwaterfor15to20minutestobesureoperationisnormal.
CAUTION: Never operate the DHW circulating pump while dry. If the unit is placed in operation
before the desuperheater piping is connected, be sure that the pump switch is set to the OFF
position.