John Wood Envirosense Power Vent - Manual (Page 17)

17
plannInG the vent sYsteM
If the water heater is being installed as a replacement for an existing
power vented heater in pre-existing venting, a thorough inspection
of the existing venting system must be performed prior to any
installation work. Verify that the 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 the joints between elbows and other fittings and the
straight runs of vent pipe. Check the system for signs of sagging
or other stresses in the 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 the installation and putting the water
heater into service.
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 this 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.
For water heaters in locations with high ambient temperatures (above
100°F) it is recommended that CPVC pipe and fittings be used. 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.
Plan the route of the vent system from the discharge of the blower
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° on top of
the unit 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 blower discharge adapter is made to accept only straight
sections of 2” pipe. To start, a minimum of 2 inches (5.1 cm) of 2”
pipe must be attached to the blower discharge, see Figure 17.
If using 2” inch vent pipe:
A minimum of 2 inches (5.1 cm) must be attached to the blower
before the first elbow. After the first elbow add the additional
venting required for the installation. The total system cannot
exceed the lengths discussed above, where each elbow is equal
to 5 feet (1.5 m) of straight pipe.
If using 3” or 4” inch vent pipe:
Two inches (5.1 cm) of pipe must be attached to the blower
discharge 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 (1.5 m) of straight pipe (3”
vent pipe) or 8 feet (2.4 m) of straight pipe (4” vent pipe).
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 boot attached to the blower and out the
fitting. The water heater is shipped with condensate hose that
attaches to the fitting on the condensate boot. No other Tee or
fitting is required. See Figures 17, 20 and 21.
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) and from two places on the blower
assembly (see figure 17). 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.
NOTE: It is important that the condensate hose on the bottom of the unit
is not installed elevated above the clamp that is secured to the side of the
jacket, see figure 16. This must be true for the entire length of the hose
from the clamp to the exit into an appropriate drain. If these instructions
are not followed or if the condensate hose is blocked, water will spill from
the condensate trap. As with every water heater installation, a metal
drain pan should be used to prevent water damage to the surrounding
area. If necessary, a condensate pump with an incorporated reservoir
may be used to pump the water to an appropriate drain. To avoid
condensate spillage, select a pump with an overflow switch.
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.