VA N TA G E
®
H E
I N S TA L L AT I O N M A N U A L
R O B E R T S
-
G O R D O N
pg 22
Section 8. Venting and Ducting
Heater must be vented in accordance with the proper
national and local codes. Partial information relating to
these specifications is provided in this section with regard
to size and configurations for venting arrangements.
United States: Refer to NFPA-54/ANSI-Z223.1 - latest
revision, National Fuel Gas Code. Canada: refer to
CAN/CGA-B149.1 and B149.2
Heater may be vented one of the following ways:
Unvented (with adequate ventilation)
pg. 24
Horizontal Venting - Combustible walls
pg. 24
Horizontal Venting - Noncombustible walls
pg. 24
Common Side Wall Venting
pg. 25
Vertical Venting without Draft Hood
pg. 26
Common Vertical Venting
pg. 27
Outside Combustion Air - Single Heater
pg. 28
Outside Combustion Air - Two Heaters
pg. 29
The method chosen will depend upon a number of factors
including: building ventilation, available access points in
walls and ceiling, number of burners installed, installation
codes, etc. Consult layout drawing for venting method
used. Some installations may require the use of an
outside combustion air supply. (See page 28 for details).
General Venting Requirements
Use the following guidelines to help insure an adequate,
safe venting arrangement: (See Figure 21.)
a) Exhaust end of heater will accept a 4" (10 cm) vent
pipe using the vent adapter (P/N 90502700). Install
the vent adapter with the seam down. This will prevent
condensation from leaking out of the adapter.
b) Vent ter minal opening must be beyond any
combustible overhang.
c) If condensation in the vent is a problem, the vent
length should be shortened or insulated.
d) For outside air installations, the outside air terminal
must not be installed more than 1 ft. (30 cm) above the
vent terminal.
e) Secure all joints with minimum (3) #8 x 3/8" sheet
metal screws.
f) All vent joints should be sealed using suitable product
such as General Electric RTV106 or Permatex Form-a-
Gasket red high temperature silicone adhesive sealant.
g) For Outdoor Installations, vent caps must be installed
at inlet and flue end. (See Figure 21.).
Vent Length Requirements (Indoor)
a) Maximum vent length allowed is 45 ft. (13.7 m).
b) Maximum outside air supply duct allowed is 45 ft.
(13.7 m).
c) Vent length plus outside air supply length shall not
exceed 65 ft. (19.8 m).
d) Under length conditions a) through c) above, a total of
2 elbows are allowed for vent and outside air supply
together. Subtract 15 ft. (4.6 m) per additional elbow
from maximum length allowed if more than 2 elbows
are used.
Figure 20b. Unvented Operation (Indoor)
TO
BURNER
Last Reflector
Last Heat Exchanger Tube
Unvented End
A
E
Building Walls and Ceiling
WARNING
Carbon Monoxide Hazard
Heaters installed unvented must
be interlocked with sufficient
building exhaust.
Heaters must be installed
according to the installation
manual.
Failure to follow these
instructions can result in death
or injury.
a
aaa
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a
a
aaa
aa
A & E are clearances to combustibles. See
Figure 1h in Section 4.
Apply Silicone Sealant
Figure 20a. Vent Cap for Outdoors