Dacor DHI542 Ventilation Hood User Manual


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pl a n t h e Du c t wo r k in S t a l l a t i o n
WARNING
Toreducetheriskoffireandtoproperlyexhaust•
air,besuretoductairoutsidethehouseorbuilding.
Donotventexhaustairintospaceswithinwallsor
ceilingsorintoattics,crawlspacesorgarages.
Tapeallductjointssecurely• topreventcombustion
by-products,smokeorodorsfromenteringthehome.
Doingsowillalsoimprovesystemefficiency.
Donotexhaustmorethanone• ventintoasingleduct.
Useonly• ductworkconstructedofmaterialsdeemed
acceptablebystate,municipalandlocalcodes.
Rangehoodsmayinterrupttheproperflowof•
smokeandcombustiongasesfromfurnaces,gas
waterheatersandfireplaces.Toavoiddrawing
lethalgasesintothehome,followthemanufactures
recommendationforthesedevicesandconsultNFPA
andASHRAErecommendations.
DO NOT• installanadditionalin-lineorexternal
blowertoincreasethelengthoftheductrun.Even
smalldifferencesbetweenblowerairflowratescan
greatlyreducetheairdrawbythehood.
Allductworkmaterials(includingscrewsandducttape)•
mustbepurchasedseparatelybythecustomer.When
planningnewductwork,alwayslookfortheshortest,
mostdirectroutetotheoutside.
Thehoodexhaustconnectstoan8-inchroundduct.•
Youcanincreasetheductsizeovertheductrunif
desired.Topreventabackdraft,neverdecreasethe
ductsizeovertherun.
Donotrelyonducttapealonetosealductjoints.•
Fastenallconnectionswithsheetmetalscrewsand
tapealljointswithducttape.Usesheetmetalscrews
asrequiretosupporttheductweight.
Topreventback-drafts,adamperattheductoutletmay•
alsoberequired.
Makesureductworkdoesnotinterferewithfloorjoists•
orwallstuds.
Calculating the Maximum Duct Run Length
Themaximumstraightductlengthforthehoodis100
feet.Foreachelbowandtransitionaddedtotheduct
work,acertainnumberoffeetmustbesubtractedfrom
themaximumstraightlengthtocompensateforwind
resistance.Todeterminethelengththeductworkcannot
exceed,subtractalloftheequivalentlengthsoftheelbows
andtransitionslistedbelowfrom100feet.
Duct Work Equivalent Lengths
DUCT PIECE SUBTRACT
90°elbow(8”Dia.) 7feet
45°elbow(8”Dia.) 3feet
31/4”x10”to8”round 4foot
Wallcapwithdamper 30feet
Roofcap 30feet
Duct Work Design Tips
Whereverpossible,reducethenumberoftransitions•
andturnstoasfewsharpanglesaspossible.Two
staggered45°anglesarebetterthanone90°.
Keepturnsasfarawayfromthehoodexhaustas•
possible,withasmuchspacebetweeneachbendas
possible.
Forbestperformance,useroundductinsteadof•
rectangular,especiallywhenelbowsarerequired.
Ifmultipleelbowsareused,trytokeepaminimumof•
24”(61cm)ofstraightductbetweenthem.
Avoid“S”or“backtoback”configurationsofadjacent•
elbows.
Inregionswheretheweathergetsextremelycold,•
thermalbreaks,suchasashortsectionofnon-metallic
duct,shouldbeusedtoavoidindoorheatloss.The
breakshouldbelocatedasclosetothepassthrough
pointtotheoutsideaspossible.
Donotuseflexiblemetalduct.•
Donot• useductworkthatissmallerincross-sectional
areathantherecommendedsizeduct(8”round).
pr e p a r i n g f o r in s T a l l a T i o n
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