Installation Guide

13
Support
NOTE: Vent Configuration to Provide
12" Minimum height above Snow Level.
1/2"
Armaflex
Insulation or
Equivalent
(if required)
12" Above
Maximum
Expected
Snow Level
19" Max.
(See Note)
Outside
Wall
Figure 9. Alternate Horizontal Vent Installation
Figure10.VerticalVentTermination
Combustion Air
Exhaust Vent
12” Above Maximum
Expected Snow Level
(Both pipes)
Elbows on the combustion air
inlet must be positioned pointing
away from the exhaust vent.
8" Min.
36" Max.
Plumbing Vent Roof Boot
(Both Pipes)
Outdoor Terminations - Vertical Venting
Termination spacing requirements from the roof and from
each other are shown in Figure 10. The roof penetration
must be properly flashed and waterproofed with a plumbing
roof boot or equivalent flashing. Vent and combustion air
piping may be installed in an existing chimney which is
not in use provided that:
• Boththeexhaustventandairintakerunthelengthof
the chimney.
• Thetopofthechimneyissealedandweatherproofed.
• The termination clearances shown in Figure 10 are
maintained.
• Noothergasredorfuel-burningequipmentisvented
through the chimney.
Vent Freezing Protection
CAUTION:
Whentheventpipeisexposedtotemperatures
below freezing (i.e., when it passes through
unheated spaces, chimneys, etc.) the pipe
mustbeinsulatedwith1/2inchthicksponge
rubberinsulation,Armaex-typeinsulationor
equivalent.Insulatingpipeisimportanttoavoid
condensate icing.
• Table2(page14)liststhemaximumlengthofuepipe
that can travel through an unconditioned space or an
exterior space. The total vent length must not exceed
the lengths noted in Table 1. For Canadian installations,
please refer to the Canadian Installation Code (CAN/
CGA-B149.1 or 2) and/or local codes.
• Forextremelycoldclimatesorforconditionsofshort
furnace cycles (i.e. set back thermostat conditions)
the last 18 inches of vent pipe can be reduced. It is
acceptable to reduce from 3” to 2-1/2”, 3” to 2”, or 2”
to 1-1/2” if the total vent length is at least 15 feet in
length, and the vent length is within the parameters
specified in Table 1 (page 11). The restriction should
be counted as 3 equivalent feet. Smaller vent pipes are
less susceptible to freezing, but must not be excessively
restrictive. The length of the 2 inch pipe must not be
longer than 18 inches.
• If furnace is installed horiziontally, make sure the
drainage port on the in-line drain assembly is pointed
downward to ensure proper drainage of condensate.
For 92.1% series, see Figures 36 & 37 (pages 46 - 47).
For 95.0% series, see Figure 41 (page 51).
• To prevent debris or creatures from entering the
combustion system, a protective screen may be installed
over the combustion air intake opening. The screens
hole size must be large enough to prevent air restriction.
• Foroptimalperformance,ventthefurnacethrougha
wall that experiences the least exposure to winter winds.
• The vent termination shall be located at least 3 ft.
horizontally from any electric meter, gas meter, regulator
and any relief equipment. These distances apply ONLY
to U.S. installations. In Canada, CSA B149.1 takes
precedence over these instructions.
• Donot install the vent terminal such that exhaust is
directed into window wells, stairwells, under decks
or into alcoves or similar recessed areas, and do not
terminate above any public walkways.
• Ifventinghorizontally,asidewallventkitisavailable
according to the pipe diameter size of the installation.
For 2 inch pipe use side wall vent kit #904617, and
for 3 inch pipe use kit #904347. Please follow the
instructionsprovidedwiththekit.
• Concentricventterminationkitsareavailableforuse
with these furnaces. For 2 Inch pipe use kit #904952
and or 3 inch pipe use kit # 904953. Pleasefollowthe
instructionsprovidedwiththekit.
• Whentheventpipemustexitanexteriorwallcloseto
the grade or expected snow level where it is not possible
to obtain clearances shown in Figure 7, a riser may be
provided as shown in Figure 9. Insulation is required
to prevent freezing of this section of pipe. See Table 3
(page 14) for vent freezing protection.