Slant/Fin VSL-160C Part B - Manual (Page 20)

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10.14.5 - Alternate vertical
concentric venting
This appliance may be installed with a concentric
vent arrangement where the vent pipe is routed
through an existing unused venting system; or by
using the existing unused venting system as a
chase for vent and combustion air routing.
Concentric Venting Arrangement
The venting is to be vertical through the roof.
The annular space between the O.D. of the vent
pipe and the I.D. of the existing unused venting
system is utilized for the combustion air source.
The minimum size of the existing vent system
required to achieve enough annular space for
combustion air is 7 inches.
The upper and lower termination as well as any
other unsealed joints in the existing vent system
must be sealed to ensure that all combustion air
is drawn from under the vent cap as shown in
Figures 10-28 and 10-29.
10 - INSTALLATION - Vent and combustion air
Figure 10-29 Alternate concentric
vertical venting (Example n°1)
Figure 10-28 Alternate concentric
vertical venting (Example n°2)
Combustion
air intake
Flue exhaust Seal
Combustion
air inlet with
screen
Seal
Seal
Flue outlet
Sealed
cap
Existing
Flue exhaust
Seal
Combustion
air intake
Existing
Combustion
air inlet with
screen
Seal
Sealed
cap
Flue
outlet
Approved venting materials must be used as
specifi ed in Tables 10-1 and 10-2.
Follow all vent / air termination and clearance
requirements per this section to the appropriate
example. Installation must comply with local
requirements and with the National Fuel Gas Code.
The maximum allowable equivalent vent and air
intake lengths for this venting arrangement are to be
determined from Section 10-4.
If an existing unused venting system is converted
for use with this method of concentric venting,
the installer must ensure that the existing
venting system is clean and free from particulate
contamination that will harm this appliance and
cause increased nuisance calls or maintenance.
See Section 10.2 for a list of corrosive contaminants
and sources.
Two example scenarios of a concentric venting
arrangement are shown for illustrative purposes in
Figures 10-28 and 10-29.
Combustion
air intake
Combustion
air intake