John Wood Polaris Commercial High-Efficiency - Manual (Page 10)

10
INLET/OUTLET VENT TERMINATIONS
Standard Horizontal Termination
When 3 inch pipe is used between the water heater and the
outside wall, reduce it to 2 inch pipe before penetrating the
wall. A maximum of 18 inches (45.7 cm) of 2 inch pipe may
be used between the 3 inch transition and the inside of the
wall (see figure 7).
The standard horizontal air inlet termination is a 2 inch
pipe which terminates at the exterior wall and utilizes a
coupling to prevent the pipe from being pushed back into the
structure. The standard horizontal exhaust outlet termination
is a 2 inch pipe which terminates 12 inches (30.5 cm) from
the outside wall. The air inlet must be located with respect to
the exhaust outlet as shown in figure 7 (bottom).
Install a drain tee assembly and trap in the inlet vent as close
to the water heater as possible. This is to drain any water
that may be in the combustion air pipe and prevent it from
entering the blower. Connect the trap drain line to a suitable
drain or downstream of the condensate trap of the water
heater.
Note: See “Venting Additional Polaris
® Units” on Page 11
for correct terminations if installing more than one Polaris ®
gas water heater.
Alternative Horizontal Termination
The combustion air and exhaust terminations may be
raised up to 24 inches (61 cm) above the wall penetrations
if required for anticipated snow levels (see figure 8). The
two elbows shown in figure 8 are considered part of the
termination and should not be included when determining
the maximum allowable vent pipe length.
Note: See “Venting Additional Polaris
® Units” on Page 11
for correct terminations if installing more than one Polaris ®
gas water heater.
(30.5 cm)
24”
(61 cm)
Max.
(76.2 cm)
Figure 7: Standard Horizontal Termination
3” (7.6cm) Max.
4” (10 cm)
Max.
4” (10 cm)
Max.
12” (30.5 cm)
2”
Coupling
12” (30.5cm) Min. Above
Grade or Anticipated
Snow Level. See
Note 4. Notes:
1. Support Horizontal Pipe Every
Four Feet (1.2 m). Support Vertical
Pipe Every Six Feet (1.8 m).
2. When Using 3 Inch Pipe, Reduce To 2 Inches Before
Penetrating The Outside Wall.
3. 18 Inch (45.7 cm) Maximum When Using 3 Inch Pipe.
4. Increase The 12 Inch (30.5 cm) Minimum Above
Grade To Keep Terminal Openings Above Anticipated
Snow Levels.
5. Slope All Piping Down Toward the Water Heater as
Follows:
‡ ´3LSLQJVORSH´3HU)RRWPPSHUPHWHU
‡ ´3LSLQJVORSH´3HU)RRWPPSHUPHWHU
*
*
*
Figure 8: Alternate Horizontal Termination