Crown Bermuda Installation Manual

For Buildings of Other than Unusually Tight Construction

1) Determinewhethertheboileristobeinstalledinaconnedspace-AconnedspaceisdenedbytheNational Fuel

Gas Codeashavingavolumelessthan50cubicfeetper1000BTU/hrinputofallappliancesinstalledinthatspace.To

determinewhethertheboilerroomisaconnedspace:

a. TotaltheinputofallappliancesintheboilerroominthousandsofBTU/hr.Roundtheresulttothenexthighest1000

BTU/hr.

b. Findthevolumeoftheroomincubicfeet.Thevolumeoftheroomincubicfeetis:

 Length(ft)xwidth(ft)xceilingheight(ft)

 Incalculatingthevolumeoftheboilerroom,considerthevolumeofadjoiningspacesonlyifnodoorsareinstalled

betweenthem.Ifdoorsareinstalledbetweentheboilerroomandanadjoiningspace,donotconsiderthevolumeofthe

adjoiningspace,evenifthedoorisnormallyleftopen.

c. DividethevolumeoftheboilerroombytheinputinthousandsofBTU/hr.Iftheresultislessthan50,theboilerroomis

aconnedspace.

Example:

 ABSI172ENandawaterheateraretobeinstalledinaroommeasuring6ft-3inx7ftwithan8ftceiling.Thewater

heaterhasaninputof30000BTU/hr:

 TotalinputinthousandsofBTU/hr=(172000BTU/hr+30000BTU/hr)/1000=202

 Volumeofroom=6.25ftx7ftx8ft=350ft

 350/202=1.73.Since1.73islessthan50,theboilerroomisaconnedspace.

2) UnconnedSpace-Naturalinltrationintotheboilerroomwillnormallyprovideadequateairforcombustionand

ventilationwithoutadditionallouversoropeningsintoboilerroom.

3) ConnedSpace-Providetwoopeningsintotheboilerroom,oneneartheoorandoneneartheceiling.Thetopedgeof

theupperopeningmustbewithin12”oftheceilingandthebottomedgeoftheloweropeningmustbewithin12”ofthe

oor(Figure3).

• Eachopeningmusthaveafreeareaof1squareinchper1000BTU/hrinputofallgasburningappliancesintheboiler

room.Theminimumopeningdimensionis3inches.Minimumopeningfreeareais100squareinchesperopening.

• Ifthetotalvolumeofboththeboilerroomandtheroomtowhichtheopeningsconnectislessthan50cubicfeetper

1000BTU/hroftotalapplianceinput,installapairofidenticalopeningsintoathirdroom.Connectadditionalrooms

withopeningsuntilthetotalvolumeofallroomsisatleast50cubicfeetper1000BTU/hrofinput.

• The“freearea”ofanopeningtakesintoaccounttheblockingeffectofmesh,grills,andlouvers.Wherescreensare

used,theymustbenonerthan¼”(4x4)mesh.

• Ifprovidingopeningsintoadjacentroomsisundesirable,combustionandventilationaircanbebroughtintotheboiler

roomfromoutdoors.Seetheinstructionsunder“ForBuildingsofUnusuallyTightConstruction”.

For Buildings of Unusually Tight Construction

1) Openingsmustbeinstalledbetweentheboilerroomandtheoutdoorsoraventilatedspace,suchasanatticorcrawl

space,whichcommunicatesdirectlywiththeoutdoors.

2) Twoopeningsarerequired.Thetopedgeoftheupperopeningmustbewithin12inchesoftheceiling.Thebottomedge

oftheloweropeningmustbewithin12inchesoftheoor.

3) Sizeopeningsandductsasfollows:

• Verticalductsoropeningsdirectlyoutdoors(Figure4,Figure5,andFigure6)-Eachopeningmusthaveafreecross

sectionalareaof1squareinchper4000BTU/hrofthetotalinputofallgas-redappliancesintheboilerroombutnot

lessthan100squareinches.Minimumopeningsizeis3inches.

• Openingstooutdoorsviahorizontalducts(Figure7)-Eachopeningmusthaveafreecrosssectionalareaof1square

inchper2000BTU/hrofthetotalinputofallgasredappliancesintheboilerroombutnotlessthan100squareinches.

Minimumopeningsizeis3inches.

• The“freearea”ofanopeningtakesintoaccounttheblockingeffectofmesh,grills,andlouvers.Wherescreensare

used,theymustbenonerthan¼”(4x4)mesh.