Vent System Options; General Venting Guidelines - RBI FUTERA III Series HeatNet Installation & Operation Manual

FUTERA III INSTALLATION AND OPERATION INSTRUCTIONS
CAUTION: A combustion air damper interlocked with
the unit should be installed in the intake air pipe when
the infi ltration of subfreezing air could occur, otherwise
the unit could freeze up voiding the warranty!
Intake Air Option – Vertical Guidelines
The maximum equivalent length for the vertical intake
air pipe is 60 ft, 18.3 m. Each 90˚ elbow and the intake
air terminal are equal to 10 linear ft, 3.0 m of pipe, see
Table 3.
An approved, nonrestrictive intake air terminal must be
used. The intake air terminal must terminate as shown in
Figure 3. The penetration point in the roof must be properly
fl ashed and sealed.
Intake Air Option – Horizontal Guidelines
The maximum equivalent length for the horizontal intake
air pipe is 60 ft, 18.3 m. Each 90˚ elbow and the intake air
terminal are equal to 10 linear ft, 3.0 m of pipe. If horizontal
runs exceed 5 ft, 1.5 m they must be supported at 3 ft,
0.9 m intervals with overhead hangers. The certifi ed intake
air terminal from RBI must be used, see Figures 1, 2
and 4.

GENERAL VENTING GUIDELINES

WARNING: The vent installation must be in
accordance with Part 7, Venting of Equipment, of
the National Fuel Gas Code, ANSI Z223.1/NFPA 54-
latest revision or applicable provisions of the local
building codes. Canadian installations must
comply with CAN/CGA B149.1 or .2 Installation
Code. Improper venting can result in excessive
levels of carbon monoxide which can result in
severe personal injury or death!
All vent systems must be fully supported by the building
structure and not by the boiler/water heater. Appropriate
thimbles and fi re-stops must be used where required.
WARNING: Common vent systems must be
properly engineered and sized to provide a
negative draft of .03 in, 0.8 mm to .1 in, 2.5 mm W.C.
at the fl ue outlet. Common positive pressure vent
systems are not to be used. Improper installation
can result in excessive levels of carbon monoxide
which can cause severe personal injury or death!

VENT SYSTEM OPTIONS

The fl ue products in the vent system may be cooled below
their dew point and form condensate in the flue. The
materials used for a Category IV vent must be resistant to
any corrosive damage from fl ue gas condensate. The fl ue
from a Category IV vent system must have a condensate
drain with provisions to properly collect and dispose of any
condensate that may occur in the venting system.
The Futera III may be vented the following ways:
1) Direct Vent, Positive Pressure, Category IV uses a
vent system certifi ed to UL 1738 for installations in the
United States, ULC S636 for installations in Canada.
Combustion air is piped from the outdoors to the
blower inlet.
2) Side Wall Vent, Positive Pressure, Category IV uses
a vent system certifi ed to UL 1738 for installations
in the United States, ULC S636 for installations in
Canada. Combustion air is obtained from the space in
which the unit is installed.
3) Vertical/Chimney Vent, Negative Pressure, Category II
uses a metal chimney system approved for Category II.
4) Vertical Vent, Positive Pressure, Category IV uses a
vent system certifi ed to UL 1738 for installations in the
United States, ULC S636 for installations in Canada.
Combustion air is obtained from the outdoors or the
space in which the unit is installed.
NOTE: All venting and combustion air material supplied
by installer. All venting materials must be approved
for the application. Consult the vent manufacturer's
product literature.
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