B
PVC Intake/Combustion Air
Concentric Vent Dimensional
Drawing
B PVC
Vent/Exhaust
D
A
1
1
/
2
²
²
25--22--03
C
Figure 47
44
440 01 2020 01
4. Dimension D may be lengthened to 60
²
max. or shortened
by cutting the pipes to 12
²
min. Dimension A will change ac-
cording to D dimension. (See
Figure 47)
Model
A*
B
C
D**
NAHA001CV
33
3
/
8
2
3
1
/
2
16
7
/
8
NAHA002CV
38
7
/
8
3
4
1
/
2
21
1
/
8
* = Dimension will change accordingly as dimension D is
lengthened or shortened.
**= Dimension D may be lengthened to 60
²
may also be short-
ened
by cutting the pipes provided in the kit to 12
²
minimum
Table 9
Concentric Termination Kit
NAHA001CV & NAHA002VC Venting
Table Dual Piping ONLY
50,000 & 75,000 Btuh Furnace
NAHA002CV --
35
¢¢¢¢
& (4) 90
°
elbows with 2
²
PVC pipe
100,000 & 125,000 Btuh Furnace
NAHA001CV --
35
¢
& (4) 90
°
elbows with 3
²
PVC pipe
1. Do not include the field supplied 45
°
elbow in the total
elbow count.
2. If more than four elbows are required, reduce the length
of both the inlet and the exhaust pipes five feet for each
additional elbow used.
3. Elbows are DWV long radius type for 2
²
and 3
²
vents.
If more than four elbows are required, reduce the length of
both the inlet and exhaust pipes 5
¢
for each additional elbow
used.
*
Feet of pipe is whichever pipe run is the longest, either inlet
or
outlet side.
If assembly needs to be extended to meet height or side wall thick-
ness requirement, the two pipes supplied in the kit may be replaced
by using the same diameter solid, single (no coupling connections)
field supplied SDR--26 PVC (ASTM D2241) pipes. Do not extend
dimension D more than 60
²
. (See
Figure 47)
Do not use field supplied couplings to extend the pipes.
Airflow restriction will occur and the furnace pressure switch
may cause intermittent operation.
5. Partially assemble the concentric vent termination kit. Clean
and cement the parts using the procedures for Joining Pipe
and Fittings section of the manual. A) Cement the Y Concen-
tric fitting to the 4
²
diameter kit pipe. (See
Figure 48)
B) Ce-
ment the 3
²
rain cap to the 2
1
/
2
²
diameter kit part. (See
Figure 48) NOTE:
A field supplied stainless steel screw
may be used to secure the rain cap to the pipe instead of ce-
menting when field disassembly is desired for cleaning (See
Figure 48)
Figure 48
Rain Cap to Vent Pipe Assembly
Drill clearance hole in rain
cap and pilot hole in vent pipe.
Stainless steel screw
(Field supplied)
25--22--02
CARBON MONOXIDE POISONING HAZARD.
Failure to follow this warning could result in death,
personal injury and/or property damage.
When using the alternate screw assembly method, drill
a clearance hole in the rain cap and a pilot hole in the
vent pipe for the screw size being used. Failure to drill
adequate holes may cause cracking of the PVC
components, allowing flue gases to be recirculated.
!
CARBON MONOXIDE POISONING HAZARD.
Failure to follow this warning could result in death,
personal injury and/or property damage.
Do not operate the furnace with the rain cap removed as
recirulation of the flue gases may occur. Water may also
collect inside the larger combustion air pipe and flow to
the burner enclosure.
!
6. Install the Y concentric fitting and the pipe assembly through
the structure’s hole. For vertical termination, install the parts
through the field supplied roof boot/flashing.
NOTE:
Do not
allow insulation or other materials to accumulate inside the
pipe assembly when installing through the structure’s hole.
7. Secure the assembly to the structure as shown in
Figure 46
or
Figure 50
using field supplied metal strapping or equiva-
lent material.
NOTE:
Ensure the termination height is above the roof sur-
face or anticipated snow level as shown in
Figure 46
for ver-
tical termination. Ensure the termination location clearance
dimensions are as shown in
Figure 49
and
Figure 50
for
horizontal termination.
Summary of Contents for 9MPT050F12A
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