John Wood Envirosense Power Direct Vent (prior to May 2010) - Manual (Page 18)

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plannInG the vent sYsteM
Plan the route of the vent system from the exhaust elbow to the
planned location of the vent terminal.
1. Layout total vent system to use a minimum of vent pipe and elbows.
2. This water heater is capable of venting flue gases equivalent to
25’ (7.6 m) of 2” pipe, 65’ (19.8 m) of 3” pipe, or 128’ (39.0 m) of
4” pipe as listed in Table 1.
taBle 1
number of 2” Maximum 3” Maximum 4” Maximum
90° elbows pipe - ft. (m) pipe - ft. (m) pipe - ft. (m)
1 20 (6.1) 60 (18.3) 120 (36.6)
2 15 (4.6) 55 (16.8) 112 (34.1)
3 10 (3.0) 50 (15.2) 104 (31.7)
4 -- 45 (13.7) 96 (29.3)
5 -- 40 (12.2) 88 (26.8)
6 -- 35 (10.7) 80 (24.3)
The minimum vent lengths for each of the pipe sizes is one 90° plus
2’ (61 cm) of straight pipe and the appropriate termination.
note: The equivalent feet (m) of pipe listed above are exclusive
of the termination. That is, the termination, with an installed
screen, is assumed to be in the system and the remainder of the
system must not exceed the lengths discussed above.
3. The exhaust elbow assembly is designed to accept only straight
sections of 2” pipe. To start, a minimum of 2” (5.1cm) of 2” pipe
must be inserted and glued to the exhaust elbow assembly if
utilizing 3” or 4” vent pipe. Use the same method with the blower
inlet if a direct vent configuration is utilized.
If using 2” inch vent pipe:
A minimum of 2” (5.1cm) diameter vent pipe must be attached
to the exhaust elbow assembly. The total system cannot exceed
the lengths discussed above, where each elbow is equal to 5
equivalent feet (1.5m) of straight pipe.
If using 3” or 4” inch vent pipe:
Two inches (5.1cm) of 2” pipe must be attached to the exhaust
elbow assembly before adding a reducer to acquire the desired
pipe diameter. An appropriately sized 45 degree elbow (supplied
locally-a schedule 40 DWV) vent terminal must be obtained with
an equivalent screen (supplied in vent kit). The total system cannot
exceed the equivalent pipe lengths discussed above where each
elbow is equal to 5 feet (1.5m) of straight pipe (3” vent pipe) or 8
feet (2.4m) of straight pipe (4” vent pipe).
Installation of this water heater must comply with can/csa
B149.1 - natural Gas and propane Installation code which
requires the vent system components be certified to ULC
s636.
This water heater has been design certified to be vented with PVC
pipe certified and marked as complying with ULC S636. This water
heater is supplied with a 2 inch 22.5 degree termination elbow
that is a special fitting that must be used with the appliance. Any
outlet piping, fittings and glue used to vent this appliance that
is not supplied by the manufacturer must comply with the ULC
S636 requirements.
If the water heater is being installed as a replacement for an existing
power vented heater in pre-existing venting, a thorough inspection of
existing venting system must be performed prior to any installation
work. Verify that correct material as detailed above has been used,
and that the minimum or maximum vent lengths and terminal location
as detailed in this manual have been met. Carefully inspect the entire
venting system for any signs of cracks or fractures, particularly at
joints between elbows and other fittings and straight runs of vent
pipe. Check system for signs of sagging or other stresses in joints
as a result of misalignment of any components in the system. If any
of these conditions are found, they must be corrected in accordance
with the venting instructions in this manual before completing
installation and putting the water heater into service.
note: a. For water heaters in locations with high ambient
temperatures (above 100°F) it is recommended that CPVC pipe
and fittings be used. B. A 22.5 degree elbow (2” vent pipe) or a
45 degree elbow (3” and 4” vent pipe) with an installed screen
VENT TERMINAL must be used in all cases.
4. There will be some installations where condensate will be formed
in the horizontal runs of the vent system. This condensate will
run into the condensate elbow. The water heater is shipped with
a condensate hose that attaches to the condensate elbow. No
other tee or fitting is required.
condensate
This water heater is a condensing unit and requires a drain to be located in
close proximity to allow the condensate to drain safely. The condensate
drains from the unit at the exhaust tee located at the bottom of the unit
(see figure 16). Condensate from this water heater is mildly acidic.
Please note that some local codes require that condensate is treated
by using a pH neutralizing filter prior to disposal.
Caution must be used to ensure that the drain is free and clear of debris
and will not allow backflow through the condensate hose. Consideration
must be given to avoid freezing of the condensate lines which could
result in excessive build up of condensate inside the water heater.
Waterproof heat tape may be required to prevent freezing of the condensate
lines. Please ensure that the outlet of the condensate drain does
not create a slippery condition which could lead to personal injury.
condensatIon warnInG: thIs water heater Is a condensInG
unIt and requIres a draIn to Be located In close
proXIMItY to allow condensate to draIn safelY. the
condensate draIns froM unIt at the eXhaust elBow
located at BottoM of unIt. note: It Is IMportant that the
condensate hose not Be elevated aBove the eXhaust
elBow, see fIGure 16. condensate BuIld-up wIll BlocK the
eXhaust outlet, whIch wIll cause IMproper operatIon.
fIGure 14.