Demand Duo
™
R
-
Series Installation and Operation Manual
17
•
Existing gas vent or chimney is to be checked
to ensure they meet clearances and local
codes.
•
This appliance can ONLY be connected to a
manufactured chimney or vent that complies
with a recognized standard.
Venting into a
masonry or concrete chimney is only
permitted as outlined in the NFPA 54/ANSI
Z223.1 National Fuel Gas Code venting
tables. It is therefore a contractual obligation
on the part of the installer to follow all safe
venting requirements.
Vent dampers must be certified in accordance
with ANSI Z21.68
Before installing any flue damper, consult the
local gas authority and damper manufacturer for
proper installation.
Thermal Operated Vent Dampers: Should NOT
be used with this appliance. This appliance has a
thermal efficiency greater than 80%. This higher
efficiency will result in lower flue gas
temperatures. Such temperatures may be too low
to activate a thermal operated vent damper. Use
of a thermal operated flue damper on this product
may result in spillage of exhaust gases and
ultimately carbon monoxide poisoning.
WARNING
This water heater is equipped with a 6 in. vent
adapter and must never be attached to a vent
smaller than 6 in. Certain applications may
require vent diameters greater than 6 in. Consult
your local gas supplier or authority to aid in the
proper vent diameter selection per the
requirements of the vent tables in the current
edition of the National Fuel Gas Code ANSI
Z223.1/NFPA 54.
The entire vent system (combustion air ducts,
louvers, exhaust vent, etc.) must be checked
periodically for signs of obstruction, rust, or dam-
age. If damaged components are observed, they
must be repaired or replaced immediately.
Screw x 3
Screw
Vent Pipe
(Min. 6 in.
diameter)
Vent Pipe
(Min. 6 in.
diameter)
Figure 7: Vent Pipe Assembly
