Dettson Chinook C105-M-V, Installation Instructions And Homeowner'S Manual

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8.8.1 Combustion air piping
Use a 90° elbow or two medium-radius sweep elbows to
keep the inlet downward and prevent the entry of rain.
The inlet opening of the combustion air termination must
be a minimum of 12” above the anticipated level of snow
accumulation.
Furnaces may have a drain tee assembly and trap in-
stalled in the combustion air pipe as close to the furnace
as possible. This is to drain any water that may enter
the combustion air pipe to prevent it from entering the
furnace vestibule area.
8.8.2 Exhaust vent piping
The adapter that attaches to the vent pipe must be used.
It seals the vent pipe to the casing and reduces the strain
on the inducer and the elbow (when present).
It is necessary to properly seal on either side of the
adapter with an appropriate adhesive. This is to prevent
any condensate leakage.
The exhaust vent must terminate at least 12” above the
combustion air termination inlet. The maximum length of
the exposed vent pipe above the roof is 30".
8.9 INSTALLING THE VENT
TERMINATION
All clearance specified in this manual are in accordance
with the current CSA B149.1, Natural and Propane In-
stallation Code and the current ANSI Z223.1/NFPA 54,
National Fuel Gas Code.
For clearance not specified in these codes, clearance
should be in accordance with local installation codes and
the requirements of the gas supplier and the instructions
in this manual.
A vent shall not terminate directly above a sidewalk or
paved driveway that is located between two single family
dwellings and serve both dwellings.
8.9.1 Concentric vent
Concentric vent can cause ice build up at the termination
and cause furnace to shutt off. This is only happening
with our low input furnace (15,000 BTU/hr and 30,000
BTU/hr). In those install, flue gases are not expelled at
a velocity to prevent ice formation. If a concentric vent
is to be use with those input, installer should intall a 1.5"
diameter pipe within th 2" diameter pipe
in the concen-
tric . Vent before the concentric shall remain 2" diameter.
This will enhance flue gas speed at the end of pipe and
will reduce the risk of ice build up.
Single or multiple concentric vent must be installed as
shown in Figure 13. Maintain the required separation dis-
tance between vents and all clearances.
Cut one 4” (102 mm) diameter hole for 2” (51 mm) kit,
or one 5” (127 mm) diameter hole for 3” (76 mm) kit
in the desired location.
Loosely assemble concentric
vent/combustion air termination components together us-
ing instructions in kit. Slide assembled kit with rain shield
REMOVED through hole in wall or roof flashing.
NOTE
: Do not allow insulation or other materials to accu-
mulate inside of pipe assembly when installing it through
hole. Disassemble loose pipe fittings. Clean and cement
using same procedures as used for system piping.
8.9.2 Two pipe termination
Two pipe vent must be installed as shown in Figure 13.
Maintain the required separation distance between vents
or pairs of vents and all clearance. Cut the required num-
ber of holes in the roof or sidewall for vent and combus-
tion air pipes. Sidewall holes for two pipes vent termina-
tions should be side-by-side, allowing space between the
pipes for the elbows to fit on the pipes. Holes in the roof
for two pipe terminations should be spaced no more than
18” (457 mm) apart. Termination elbows will be installed
after the vent and combustion air pipe is installed.
Table 6 – Maximum equivalent vent length (Ft) for altitude up to 4500 Ft
Unit size Vent pipe dia. Vent pipe dia.
BTU/hr 2" 3" and 4"
15,000 300 N/A
30,000 180 N/A
45,000 70 90
60,000 70 90
75,000 70 90
105,000 15 80
120,000 10 40
30