2
support material.
imporTanT: Make sure the termination height is above
the roof surface or anticipated snow level (12 inches
in U.S.A. or 18 inches in Canada). If the assembly is
too short to meet the height requirement, the 2 pipes
supplied in the kit may be replaced by using the same
diameter, field supplied SDR-26 PVC (D2241) pipe. Do
not expand dimension "D" more than 60 inches. See
Figure 3.
Warning:
do not operate the furnace with rain cap removed.
recirculation of combustion products may
occur, or water may accumulate inside larger
combustion air pipe and flow into the burner
enclosure. Failure to follow this warning could
result in product damage or improper operation,
personal injury or death.
CauTion:
do noT use field supplied couplings to extend
pipes. airflow restriction will occur and the
furnace pressure switch may cause intermittent
operation.
noTe: Instead of cementing the smaller pipe to the rain
cap, a field-supplied stainless steel screw may be used to
secure the 2 components together when field disassembly
Figure 1. Kit Components
Figure 2. dimensions
B
1 3/16
1 1/2
D
F
A
E
C In. Dia.
KiT no.
a
B
C
d
e
F
904176 (3”) 38 7/8
3
4 1/2
21 1/8
7 3/8
6 1/2
904177 (2”) 33 3/8
2
3 1/2
16 5/8
6 1/4
5 3/4
904952 (2”) 33 /38
2
3 1/2
16 5/8
6 1/4
5 3/4
904953 (3”) 38 7/8
3
4 1/2
21 1/8
7 3/8
6 1/2
inSTallaTion
Warning:
These kits are to be used only for terminating
condensing Category iV furnaces. do noT use
kits to terminate Category i, ii, or iii vent furnaces.
Failure to follow these instructions could result
in fire, personal injury, or death.
The concentric vent is made of pVC. When joining PVC
to PVC, use cement that conforms to ASTM standard
D2564. PVC primer must meet standard ASTM F656.
When joining ABS to ABS, use cement that conforms to
ASTM standard D2235. When joining PVC to ABS, use
cement as specified in procedure from ASTM standard
D3138.
In Canada, all plastic vent pipes and fittings including
any cement, cleaners, or primers must be certified as a
system to ULC S636. However this requirement does not
apply to the finish flanges or piping internal to the furnace.
Consult your furnace installation instructions for the
allowable length and size of the plastic vent pipe. The
concentric vent termination assembly is equal to 4 feet of
3" inlet and outlet pipe, or 3 feet of 2" inlet and outlet pipe.
The concentric vent termination kit is shipped assembled
but not cemented. Disassemble the kit and cement as
shown in Figures 1 and 2.
procedure 1: roof Termination
1. Determine the best location for the termination kit. Refer
to the Installation Instructions supplied with the furnace.
2. Cut one hole, 5” diameter when using a 3" kit or a 4"
diameter hole when using a 2" kit.
3. Partially assemble the concentric vent termination kit
as shown in Figures 1 and 2.
a. Cement Y concentric vent fitting to larger diameter
kit pipe. See Figure 1.
b. Cement rain cap to smaller diameter kit pipe. See
Figure 1.
4. Install cemented Y concentric fitting and pipe assembly
through structure's hole and field supplied roof boot/
flashing. See Figure 3 (page 3).
noTe: Do not allow insulation or other materials to
accumulate inside pipe assembly when installing through
hole.
5. Secure assembly to roof structure as shown in Figure
3 using field supplied metal strapping or equivalent
KiT no.
deSCripTion
uSage
Inside Pipe
Y Concentric
Fitting
Outside Pipe
Rain Cap
904176
Concentric Vent Kit, 3 inch, US
US Only
904177
Concentric Vent Kit, 2 inch, US
US Only
904952 Concentric Vent Kit, 2 inch, US/CAN US/CAN
904953 Concentric Vent Kit, 3 inch, US/CAN US/CAN
