9
FUTERA II INSTALLATION AND OPERATION INSTRUCTIONS
Table 3 – Category III Equivalent Length Per Fitting
DIRECT VENT,
POSITIVE PRESSURE, CATEGORY III
In this configuration the boiler/water heater blower is used
to push the flue products to the outdoors while drawing
combustion air from the outdoors. The equivalent length
of the vent system must not exceed
60 ft.
, 18.3 m. The
Intake
Air Option instructions under the “COMBUSTION
AIR &
VENTILATION” section must be followed! The vent
system must be sized per Figure 2, Outlet Sizes.
Horizontal Direct Vent Systems – Figures 3 & 4
The vent materials used in horizontal vent systems must
be certified to UL 1738 for installations in the United States,
ULC S636 for installations in Canada. The certified vent
terminal from RBI must also be used.
The maximum equivalent length for the horizontal vent
pipe is
60 ft
,
18.3 m. If any part of a single wall
metal vent system passes through an unheated
space, it must be insulated with insulation rated for
400°F
, 204°C. Structural penetrations must be made using
approved fire-stops. For best results, horizontal vent
systems should be as short and straight as possible.
The vent system must be both gas tight and watertight. All
seams and joints in metal pipes must be joined and sealed
in accordance with the vent system manufacturer’s
instructions.
When horizontal vent runs exceed
5 ft
, 1.5 m they must be
supported at
3 ft
, 0.9 m intervals with overhead hangers.
The vent system must be pitched down, toward the vent
terminal,
1/4 in/ft
, 20 mm/m. If any part of a single wall metal
vent system passes through an unheated space it must be
insulated with insulation rated for
400°F
, 204°C.
Horizontal vent systems shall terminate at least
4 ft
,
1.2 m below,
4 ft
, 1.2 m horizontally from or
1 ft
,
0.30 m above any door, window or gravity air inlet into
any building. It must not terminate less than 4 ft, 1.2 m
horizontally from, and in no case above or below, unless
a
4 ft
, 1.2 m horizontal distance is maintained, from electric
meters, gas meters, regulators and relief equipment and
not less than
7 ft
, 2.1 m from any adjacent public walkway.
The bottom of the vent terminal(s) shall be located at
least
5 ft
, 1.5 m above the air intake terminal(s) unless
there is a minimum
5 ft
, 1.5 m horizontal separation
between them. Avoid terminal locations likely to be affected
by winds, snowdrifts, people and pets. Protect building
materials and vegetation from degradation caused by the
flue gases.
Vertical Direct Vent Systems – Figure 5
The maximum equivalent length for the vertical pipe is
60 ft
, 18.3 m. If any part of a single wall metal vent
system passes through an unheated space, it must be
insulated with insulation rated for
400°F
, 204°C. Structural
penetrations must be made using approved fire-stops.
An approved nonrestrictive intake air teminal must be
used. The top of a vertical vent system must extend at least
5
1
/
2
ft
,
1.7 m above the roof surface and maximum snow
line that it passes through,
4 ft
, 1.2 m above the intake air
terminal, see Figure 5.
In addition the vent system must conform to the dimensions
shown in Figure 5. The penetration point in the roof must
be properly flashed and sealed.
The vent system must be gas tight. All seams and joints
in metal pipes must be joined and sealed in accordance
with the vent system manufacturer’s instructions.
Combination Direct Vent Systems – Figure 6
The boiler/water heater can be vented vertically with the
intake air piped horizontally through an outside wall. Follow
the instructions in the Intake Air Option –
Horizontal
Guidelines on page 5. Also follow the general instructions
in the “COMBUSTION AIR & VENTILATION” and
“GENERAL VENTING GUIDELINES” sections.
Model/Outlet
K
Equivalent Feet of Straight Pipe (ft) - Futera II Series
500
6"
750
8"
1000
9"
1250
10"
1500
10"
1750
12"
2000
12"
Standard Tee
1.25 25 ft 35 ft 35 ft 40 ft 40 ft 40 ft 40 ft
Boot Tee
0.65 15 ft 15 ft 15 ft 20 ft 20 ft 20 ft 20 ft
Cap - Low Res (UL) 0.50 10 ft 15 ft 15 ft 15 ft 15 ft 15 ft 15 ft
45° w/Bird Screen
0.40 10 ft 10 ft 10 ft 15 ft 15 ft 15 ft 15 ft
Elbow - 90°
0.38 10 ft 10 ft 10 ft 15 ft 15 ft 15 ft 15 ft
Elbow - 45°
0.15 5 ft
5 ft
5 ft
7 ft
7 ft
7 ft
7 ft
*Equivalent lengths based on listed K-Factors
