Kenmore KWX-3V Owner's Manual page 5

I Provision for combustion and ventilation air must be in accordance with Section 5.3, Air for Combustionand Ventilation, of
the National Fuel Gas Code, ANSI Z223.1-1atest revision, or applicable provisionsof the local building codes.
WARNING
Be sure to provide enough fresh air for combustion.
Enough air insures proper combustion and assures that
no hazard will develop due to the lack of oxygen.
Youmustprovideforenough freshair toassure propercombustion. Thefire
in the boiler usesoxygen.It musthavea continuoussupply.Theair in a
housecontainsonly enoughoxygen to supplylhe burnerfor a short time.
Outside air mustenterthehouseto replace that usedbytheburner.Study
followingexamples 1 and2 to determine yourfreshair requirements.
EXAMPLE1: Boiler Locatedin UnconfinedSpace
An unconfined spaceis definedas a spacewhosevolumeis not lessthan
50 cubicfeelper1,000Bluperhourof thelotalinputratingof all appliances
installedin thatspace.
If your boiler is in an openarea(unpartitioued basement) in a conventional
house,theair thatleaksthroughthecracks arounddoorsandwindows will
usuallybe adequate t o provideair forcombustion. T hedoorsshouldnotfit
tightly.Donotcaulkthecracks aroundthewindows.
Equipment located in buildingsof unusually tight construction shallbepro-
videdwith air for combustion, v entilation, a nd dilutionol flue gases using
themethods described in example 2B or shall bespecially engineered. The
authorityhavingjurisdictionmustapprovespeciallyengineered installa-
tions.
EXAMPLE2: Boiler Locatedin ConfinedSpace
/L All Air from Inside the Building:Theconfinedspace shall bepro-
videdwith twopermanent openings communicating d irectlywithanaddi-
tional room(s) o f sufficientvolumeso thatthecombinedvolumeof all
spacesmeetsthe criteriafor an unconfined space.Thetotal input of all
gas:utilization equipment i nstalledin the combined spaceshallbe con-
sideredin makingthis determination. Eachopeningshall havea mini-
mumfreearea of onesquareinchper1,000Btuperhourol thetotalinput
ratingof all gasutilizationequipment i n theconfined space,butnot less
that 100squareinches. O neopening shallbewithin 12 inches of thetop
and onewithin 12 inchesof the bottomof theenclosure. T heminimum
dimension of air openingsshallnol be lessthan3 inches.
B. All Air from Outdoors: Theconfined space shallcommunicate w iththe
outdoorsin accordance w ith methods 1 or 2.Theminimumdimension of
air openingsshallnot belessthan3 in. Where ductsareused,theyshall
be of thesamecross-sectional areaas the freeareaof theopeningsto
whichtheyconnect.
1. Twopermanent o penings,one commencing within 12 inchesof the
top,andonecommencing within12 inchesoftheboltom,ol theenclo-
sureshallbeprovided. T heopenings shallcommunicate directly,or by
theducts,with theoutdoors or spaces (crawlor attic)thaifreelycom-
municate with the ouldoors.
a) Where directlycommunicating w ith theoutdoors or where commu-
nicatingto theoutdoorsthroughvertical d ucts,eachopening shag
havea minimumtreeareaof 1 sq. in. per4000Btuperhourof total
inputratingof all equipment i n theenclosure. ( SeeFigure3A.)
b)Wherecommunicating with the outdoors throughhorizontal d ucts,
eachopeningshal!havea minimumfreeareaof 1 sq. in. per2000
Blu perhour of total inputratingof all equipment i n theenclosure.
(SeeFigure3B.)
2. Onepermanent opening commencing with 12 inches of thelop of the
enclosure, s hallbe permitted wherethe equipment hasclearance of at
NOTE
If you use a fireplace or a kitchen or bathroom exhaust
fan, you should install an outside air intake. These
devices will rob the boiler and water heater of combus-
tion air.
least1 inchfromthesidesandback and 6 inches lromIhefronlof the
appliance. T heopening shall directlycommunicate w ith Ihe outdoors
or shallcommunicate t hrougha vertical o r horizonlal d uct to theoub
doorsor spaces (crawlor attic)thatfreelycommunicate w ith theout-
doors,andshallhavea minimumfreeareaof:
a) 1 sq. inchper3000Btuperhour ol theIolalinputof aft equipment
located in lhe enclosure (SeeFigure4), and
b) Not lessthanthesumof theareasof all venlconnectors i n thecon-
finedspace.
Figure 3A - FRESH AIR DUCT CAPACITIES (Btuh) i
Fresh Air
Duct Size
3"x 12"
8" x 8"
8" X 12"
81/2" X 16"
1 Square Inch per 4,000 Btuh
100% Free 75% Free
Area Area
1/4"Wire Metal
Mesh Louvers
144,000 108,000
256,000 192,000
384,000 288,000
512,000 384,000
25% Free
Area
Wood
Louvers
36,000
64,000
96,000
128.000
I 3B - FRESH AIR DUCT CAPACITIES (Btuh) I
Figure
1 Square Inch per 2,000 Btuh
Fresh Air
Duct Size
3" x 12"
! 8" x 8"
8"x 12"
81/2" x 16"
100% Free 75% Free
Area Area
V4" Wire Metal
Mesh Louvers
72,000 54,000
128,000 96,000
192,000 144,000
256,000 192,000
25% Free
Area
Wood
Louvers
18,000
32,000
48,000
64,000
I FRESH AIR DUCT CAPACITIES (Btuh) i
I
Figure 4
1 Square Inch per 3,000 Bruh
100% Free 75% Free 25% Free
Area Area Area
Fresh Air V,¢' W ire Metal Wood
Duct Size Mesh Louvers Louvers
3" x 12" 108,000 81,000 27,000
8" x 8" 192,000 144,000 48,000
8" x 12" 288,000 216,000 72,000
8V2"x 18" 384,000 288,000 96,000
5