Instruction Manual

3
B. Ducting for Dehumidification
Fortheidealinstallation,drawairfromthecentralpartofthehomeandreturnittotheisolatedareasofthehomelikethe
bedrooms,den,utilityroom,orfamilyroom.TheductworkoftheexistingHVACsystemcanbeusedtosupplyairtothe
home.Iftheexistingsupplyductadequatelyservesallareasofthehome,dischargethesupplyairoftheDH70intothe
returnoftheexistingHVACsystemwhereitcandistributedthroughoutthespace.Theexistingreturnduct,ifadequate,
maybeusedasreturnfortheDH70,DO NOTdrawairdirectlyfromthekitchen,laundry,orisolatedbasement.Youmay
drawairfromabasementthatisopentothehome.AllexibleductingconnectedtotheDH70shouldbeapprovedby
localcodesandinmostcasesinsulated.
• Returnairductsshouldbedesignedtoallowunimpededairowtothereturnsideofthesystem.Forreturnsless
than10’inlength,an8”roundorequalmaybeutilized.Multiplereturnsareacceptable.
• ThesupplyairoutletandthereturnairinletarelocatedoneachendoftheDH70.Alengthofacousticalex
ductingontheoutletoftheDH70willreduceairnoise.AlengthofexibleductingonallDH70ductconnectionsis
recommendedtoreducenoiseandvibrationtransmittedtorigidductworkinthestructure.
• DuctingtheDH70asmentionedinthe“Ducting”sectionsrequiresconsiderationofthefollowingpoints:
• DuctSizing:Fortotalductlengthsupto10’,useaminimum8”diameterroundorequivalentrectangular
Forlongerlengths,upto25’,useaminimum10”diameterorequivalentductsize.Grillsordiffusers
utilizedmustnotexcessivelyrestrictairow.
• IsolatedAreas:Effectivedehumidicationmayrequirethatductingbebranchedtoisolated,stagnant
areas.Use8”orlargerdiameterbranchductingtoeachoftwoorthreeareas,use6”orlargertoeachof
fourormoreareas.
ConnectingtoExistingHVACSystems:Forproperoperation,connectingtoexistingairhandlerandductsystems
requiresthefansofeachsystemtobeinterlockedutilizingthelowvoltageinterlockmethodprovidedintheDH70low
voltageconnectiondiagram.Refertolowvoltageconnectiondiagraminthisdocumentandontheunit.
C. Installation in a Basement or Crawl Space with an Existing Forced Air HVAC System (Whole
House Dehumidification)
IfthestructureinwhichtheDH70SystemistobeinstalledhasanexistingforcedairHVACsystem,andthissystem
servestheareasthataredesiredtobecontrolled,utilizetheHVACsystemtomaketheDH70Systeminstallationeasier
andprovidebetterwholehousetypesystemperformance.
Basement or Crawl Space Installation: Installaseparate8”returnfortheDH70inacentralareaofthestructureorif
thereturnductingisadequatetapintotheexistingreturnductsystemnearthereturnairgrill.Ductthesupplyofthe
DH70SystemtothereturnductingoftheexistingHVACsystem.Thefaninterlockprovisionmustbeutilizedforproper
systemperformance.
D. Installation in an Attic with an Existing Forced Air HVAC System (Whole House
Dehumidification)
ALWAYSinstallasecondarydrainpanwithadrainoroatinterruptforcondensationundertheDH70inanatticto
preventcondensateoverowthatmaydripdowndamagingtheceilingorlivingspacebelow.
Installaseparate8”returnfortheDH70inacentralareaofthestructureorifthereturnductingisadequatetapinto
theexistingreturnductsystemnearthereturnairgrill.DuctthesupplyoftheDH70Systemtothereturnductingofthe
existingHVACsystem.Thefaninterlockprovisionmustbeutilizedforpropersystemperformance.
E. Installation in a Structure with Two Forced Air HVAC Systems (Whole House
Dehumidification)
AttachtheDH70returntoanindependentreturnfromtheupperlevel.AttachtheDH70supplytothereturnofthe
basementHVACsystem.Thiswillpromotecirculationofairthroughthewholestructurefromtheupperleveltothelower
levelthroughtheDH70.IftheDH70isnotconnectedtobothHVACsystems,itmaynotcontrolthehumidityoftheentire
structure.Thefaninterlockprovisionshouldbeconnectedtothelower,ducted,HVACsystemandmustbeutilizedfor
propersystemperformance.