9
Gas Code, ANSI Z223.1/NFPA 54 or the Natural Gas and
Propane Installation Code CAN/CSA B149.1.
PLANNING THE VENT SYSTEM
Plan the route of the vent system from the discharge of the blower
to the planned location of the vent terminal.
1. Layout the total vent system to use a minimum of vent pipe
and elbows. Take into consideration that an elbow will be
necessary to make the first vent pipe connection to the power
venter outlet (see Figure 6).
2. This water heater is capable of venting the flue gases
the equivalent of thirty (30) feet (9.1 m) of 3 inch pipe or
one-hundred (100) feet (30.5 m) of 4 inch pipe as listed
in Table 1.
TABLE 1
Number of
3" Maximum
4" Maximum
90° Elbows
Pipe
Pipe
ONE (1)
25 ft (7.6 m)
92 ft (28.0 m)
TWO (2)
20 ft (6.1 m)
84 ft (25.6 m)
THREE(3)
15 ft (4.6 m)
76 ft (23.2 m)
FOUR (4)
10 ft (3.0 m)
68 ft (20.7 m)
FIVE (5)
- - -
60 ft (18.3 m)
Minimum of one (1) elbow and 2 feet (61 cm) of straight pipe
must be installed for 3" and 4" pipe.
NOTE:
The equivalent length of pipe listed above are exclusive
of the "45° Elbow" termination. That is, the termination "45°
Elbow", with installed screen, is assumed to be in the system
and the remainder of the system must not exceed the thirty
(30) equivalent feet (9.1 equivalent meters) of 3 inch pipe or
one-hundred (100) equivalent feet (30.5 equivalent meters) of
4 inch pipe.
3. The blower discharge adapter is made to accept only straight
sections of 3" pipe. To start a minimum of 2 inches (5.1 cm)
of 3" pipe must be attached to the blower discharge (See
Figure 6).
If using 3 inch vent pipe:
A minimum of 2 inches (5.1 cm), maximum of 4 feet (1.2 m)
of 3" pipe must be attached to the blower before the first 3
inch elbow. After the first elbow add the additional venting
required for the installation. The total system cannot exceed
30 equivalent feet (9.1 equivalent meters) of venting, where
each elbow is equal to 5 feet (1.5 m) of straight pipe.
If using 4 inch vent pipe:
Two inches (5.1 cm) of 3" pipe must be attached to the
blower discharge. A 4" x 3" reducer is added and then up
to maximum 4 feet (1.2 m) of 4 inch pipe added before the
first elbow. An additional 4" x 3" reducer and (1) foot (30
cm) of 3" pipe must be added to the end of the vent system
before terminating into the 3" 45° elbow. The total system
cannot exceed 100 equivalent feet (30.5 equivalent meters)
of 4" venting, where each elbow is equal to 8 feet (2.4 m) of
straight pipe.
FIGURE 4
NOTE:
This unit can be vented using only PVC (Class 160,
ASTM D-2241; Schedule 40, ASTM D-1785; or Cellular Core
Schedule 40 DWV, ASTM F-891), Schedule 40 CPVC/ASTM
F-441), or ABS/ASTM D-2661) pipe. The fittings, other than the
TERMINATION 45° ELBOW should be equivalent to PVC-DWV
fittings meeting ASTM D-2665 (Use CPVC fittings, ASTM F-438
for CPVC pipe and ABS fittings, ASTM D-2661/3311 for ABS
pipe. If CPVC or ABS pipe and fittings are used, then the proper
cement must be used for all joints, including joining the pipe
to the Termination 45° Elbow (PVC Material). If local codes do
not allow the use of the PVC termination when a material other
than PVC is used for venting, than an equivalent fitting of that
material may be substituted if the screen in the PVC terminal
is removed and inserted into the new fitting.
PVC Materials should use ASTM D-2564 Grade Cement; CPVC
Materials should use ASTM F-493 Grade Cement and ABS
Materials should use ASTM D-2235 Grade Cement.
NOTE:
A.
For water heaters in locations with high ambient
temperatures above 100°F (38°C) and/or insufficient dilution
air, it is recommended that CPVC or ABS pipe and fittings
be used.
B.
The SUPPLIED VENT TERMINAL or a precisely
identical vent terminal of CPVC or ABS material must be used
in all cases. If a new terminal is used, the screen inside the
supplied terminal must be installed into the new terminal.
4. The temperature of the flue gases leaving the blower is about
160°F (71°C) after mixing the dilution air in the inlet adapter of
the blower. Even with high concentrate of room air taken into
the vent system for dilution air, there will be some installations
where condensate will be formed in the horizontal runs of the
vent system.
CONDENSATE
Condensate formation does not occur in all installations of
power vented water heaters, but should be protected against
on installations where it can form in the venting system.
Condensation in the venting system of power vented water
heaters is dependent upon installation conditions including, but
not limited to ambient temperature and humidity of installation
location, ambient temperature and humidity of venting space,
vent discharge and slope, and product usage. In certain
conditions, installations in unconditioned space or having long
horizontal or vertical vent runs may accumulate condensate.
In these conditions, the vent pipe should be sloped downward
away from the blower assembly (not less than 1/8" (3.2 mm)
nor greater than 1/2" (12.7 mm) per foot (30 cm) maximum).
If the vent piping is vented level or sloped upwards away from
the blower assembly, then adequate means for draining and
disposing of the condensate needs to be made by the installer
(if condensate is detected). If you have condensate, then a
