Superior VRT3542WS - Combustion and Ventilation Air Requirements; Cold Climate Insulation

NOTE:DIAGRAMS&ILLUSTRATIONARENOTTOSCALE.
4
Youroptionsare:
a.Reworkequationsaddingthespaceofadjoin-
ingroom(s).Iftheextravolumeprovidesan
unconnedspace,thenremovedoororadd
ventilation grills between rooms. Refer to
National Fuel Gas Code, ANSI Z223.1 - latest
edition, Section on Air for Combustion and
Ventilation.
b. Vent room directly to the outdoors. Refer to
National Fuel Gas Code, ANSI Z223.1 - latest
edition, Section on Air for Combustion and
Ventilation.
c.InstallalowerBTU/Hrheater,suchasa21,000
BTU/Hr, to make the area an unconned
space.
If the actual BTU/Hr used is less than the
maximumBTU/Hrthespacecansupport,then
the space is an unconned space. You will
need no additional fresh air ventilation for an
unconnedspace.
This appliance shall not be installed in a room
orspaceunlesstherequiredvolumeofindoor
combustion air is provided by the method
described in the National Fuel Gas Code, ANSI
Z223.1/NFPA 54, the International Fuel Gas
Code, or applicable local codes.
Maintain adequate clearances around air
openings.
Maintainadequateclearancesforaccessibility
for purposes of servicing and proper operation.
COLD CLIMATE INSULATION
For cold climate installations, seal all cracks
around the appliance with noncombustible
material and wherever cold air could enter
the room. It is especially important to insulate
outside cavities between studs and under floor
on which the appliance rests, if floor is above
ground level. Gas line holes and other openings
should be caulked with high temperature caulk
orstuffedwithunfacedberglassinsulation.If
thereplaceisbeinginstalledonacementslab,
in cold climates, a sheet of plywood or other
raised platform can be placed underneath to
prevent conducting cold up into the room. It also
helps to
sheetrock inside surfaces and tape for
maximumairtightnessandcaulkrestops.
3.AddtheBTU/Hrofallthefuelburningappli-
ances in the space.
Vent-Free heater ________  BTU/Hr
Gas appliance #1* ________  BTU/Hr
Gas appliance #2 +________  BTU/Hr
Total =________  BTU/Hr
Example:
Vent-freeheater 26,000 BTU/Hr
 Gasappliance#1 40,000 BTU/Hr
(water heater)
  Total= 66,000 BTU/Hr
* Do not include direct-vent gas appliances.
Direct-vent is sealed combustion and draws
combustion air from the outdoors.
4.ComparethemaximumBTU/Hrthespacecan
supportwiththeactualamountofBTU/Hr
used.
_________ BTU/Hr
 (max.thespacecansupport)
_________ BTU/Hr
 (actualamountofBTU/Hrused)
Example:
 61,440 BTU/Hr
 (max.thespacecansupport)
 66,000 BTU/Hr
 (actualamountofBTU/Hrused)
Thespaceintheaboveexampleisaconned
spacebecausetheactualBTU/Hrusedismore
thanthemaximumBTU/Hrthespacecansup-
port. You must provide additional fresh air.
WARNING
If the area in which the heater may be
operated does not meet the required
volume for indoor combustion air,
combustion and ventilation air shall
be provided by one of the methods
described in the National Fuel gas
Code, ANSI Z223.1/NFPA 54, the Inter-
national Fuel gas Code, or applicable
local codes.
TheNationalFuelGasCodedenesaconned
space as a space whose volume is less than
50 ft
3
per1,000BTU/Hr(4.8m
3
per kw) of the
aggregate input rating of all appliances installed
inthatspaceandanunconnedspaceasaspace
whose volume is not less than 50 ft
3
per 1,000
BTU/Hr(4.8m
3
per kw) of the aggregate input
rating of all appliances installed in that space.
Rooms communicating directly with the space
in which the appliances are installed, through
openings not furnished with doors, are consid-
eredapartoftheunconnedspace.
Unusually tight construction is dened as
constructionwhere:
a.Wallsandceilingsexposedtotheoutside
atmosphere have a continuous water vapor
retarder with a rating of one perm or less with
openings gasketed or sealed, and
b.Weatherstrippinghasbeenaddedonoper-
able windows and doors, and
c. Caulking or sealants are applied to areas such
asjointsaroundwindowanddoorframes,
between sole plates and floors, between
wall-ceilingjoints,betweenwallpanels,at
penetrations for plumbing, electrical, and
gas lines, and at other openings.
Usethefollowingequationstodetermineifyou
haveaconnedorunconnedspace.
1. Determine the volume of space — ft
3
.
 LengthxWidthxHeight= _____ ft
3
 (Include adjoining rooms with doorless
passageways or ventilation grills between
rooms).
Example:24'(L)x16'(W)x8'(H)=3072
ft
3
2. Divide the volume of space by 50 ft
3
to
determinethemaximumBTU/Hrthespace
can support.
(volume of space – ft
3
)/ 50 ft
3
=(Maximum
BTU/Hrthespacecansupport)
Example: 3072 ft
3
/ 50 ft
3
=61.44
 or61,440BTU/Hrthespacecansupport.