Operating instructions

WARNING: Vent pipe must be installed and fully
seated against inducer housing. Clamp must be tightened
to prevent any condensate leakage. Failure to follow this
warning could result in electrical shock, fire, personal
injury, or death.
NOTE: A 2-in. diameter pipe must be used within the furnace
casing. Make all pipe diameter transitions outside furnace casing.
VENT EXTENSION PIPE
Some furnaces are supplied with a PVC vent extension pipe
(2-in. diameter by 12-in. long). This pipe has a built-in
channel to assist vent condensate disposal. When this vent
extension pipe is supplied, it must be used to connect the
field vent pipe to furnace inducer housing on ALL upflow
and downflow applications.
NOTE: See label on vent extension pipe for proper installation.
This pipe may be shortened if an elbow is used to connect vent
extension tube to field-installed vent pipe.
3. Working from furnace to outside, cut pipe to required
length(s).
4. Deburr inside and outside of pipe.
5. Chamfer outside edge of pipe for better distribution of
primer and cement.
6. Clean and dry all surfaces to be joined.
7. Check dry fit of pipe and mark insertion depth on pipe.
NOTE: It is recommended that all pipes be cut, prepared, and
preassembled before permanently cementing any joint.
8. After pipes have been cut and preassembled, apply gener-
ous layer of cement primer to pipe fitting socket and end of
pipe to insertion mark. Quickly apply approved cement to
end of pipe and fitting socket (over primer). Apply cement
in a light, uniform coat on inside of socket to prevent
buildup of excess cement. Apply second coat.
9. While cement is still wet, twist pipe into socket with 1/4
turn. Be sure pipe is fully inserted into fitting socket.
10. Wipe excess cement from joint. A continuous bead of
cement will be visible around perimeter of a properly made
joint.
11. Handle pipe joints carefully until cement sets.
12. Support combustion-air and vent piping a minimum of
every 5 ft (3 ft for SDR-21 or -26 PVC) using perforated
metal hanging strap.
13. Slope combustion-air and vent pipes toward furnace a
minimum of 1/4 in. per linear ft with no sags between
hangers.
14. Use appropriate methods to seal openings where vent and
combustion-air pipes pass through roof or side wall.
III. CONCENTRIC VENT AND COMBUSTION-AIR
TERMINATION KIT INSTALLATION
NOTE: If these instructions differ from those packaged with
termination kit, follow kit instructions.
Combustion-air and vent pipes must terminate outside structure. A
factory accessory termination kit must be installed in 1 of the
installations shown in Fig. 30, 31, 32, 33, or 34. Four termination
kits are available.
1. The 2-in. termination bracket kit is for 1-in., 1-1/2 in., and
2-in. diameter 2-pipe termination systems.
2. The 3-in. termination bracket kit is for 2-1/2 in. and 3-in.
diameter 2-pipe termination systems.
3. The 2-in. concentric vent/air termination kit is for 1-in.,
1-1/2 in., 2-in., and 2-1/2 in. diameter pipe systems when
single penetration of wall or roof is desired.
TABLE 5—MAXIMUM ALLOWABLE PIPE LENGTH (FT) Continued
ALTITUDE UNIT SIZE
TERMINATION
TYPE
PIPE DIA
(IN.)*
NUMBER OF 90° ELBOWS
1234 5 6
9001 to 10,000‡
024040
036040
2 Pipe or 2-In.
Concentric
1-1/2 42 37 32 27 25 20
2 57555351 49 47
024060
036060
048060
2 Pipe or 2-In.
Concentric
2 45403833 31 29
036080
048080
060080
2 Pipe or 2-In.
Concentric
2 302514 9 7 NA
2-1/2 57 55 53 51 49 47
048100
060100
2 Pipe or 3-In.
Concentric
2-1/2 21 13 5 NA NA NA
3 54494439 34 29
060120
2 Pipe or 3-In.
Concentric
3† one disk 18 16 14 9 7 5
3† no disk 39 37 35 33 31 29
* Disk usage—Unless otherwise specified, use perforated disk assembly (factory-supplied in loose parts bag). If stated, separate 2 halves of perforated disk assembly and
use shouldered disk half or no disk assembly.
† Wide radius elbow.
‡ Vent sizing for Canadian installations over 4500 ft (1370 m) above sea level are subject to acceptance by the local authorities having jurisdiction.
NA—Not Allowed; pressure switch will not make.
NOTES:
1. Do not use pipe size greater than those specified in table or incomplete combustion, flame disturbance, or flame sense lockout may occur.
2. Size both the combustion-air and vent pipe independently, then use the larger diameter for both pipes.
3. Assume two 45° elbows equal one 90° elbow. Long radius elbows are desirable and may be required in some cases.
4. Elbows and pipe sections within the furnace casing and at the vent termination should not be included in vent length or elbow count.
5. The minimum pipe length is 5 ft for all applications.
Fig. 29—Intake Housing Plug Fitting Drain
A93035
COMBUSTION –
AIR PIPE

BURNER
BOX
COMBUSTION – AIR
INTAKE HOUSING
3/8" ID TUBE
TRAP
TO OPEN
DRAIN
3/16"
DRILL
4″
MIN
—25—