25
VENT INSTALLATION CONSIDERATIONS
This water heater can be vented using room air for intake
combustion air, or direct vented so that all intake air for
combustion comes from the outside through a sealed pipe.
This water heater may be installed in 4 separate orientations
depending on the requirements of the building and the water
heater. The installer must decide which method is most
appropriate for each installation. These orientations are:
1.
Vertical Termination - vertical vent termination through
unenclosed or enclosed areas with roof penetration, refer
to Vertical Vent Terminal Installation on Page 31.
2.
Through-the-Wall Termination - horizontal vent termination
directly through an outside wall, see Figure 12 on page 27..
3.
Horizontal Direct Vent - using Through-the-Wall Termination
to exhaust flue products and piping to bring combustion air
to the water heater from the outside. See Figure 15 on
Page 28 and Figure 23 and Figure 24 on page 32.
4.
Vertical Direct Vent - using a vertical vent termination to
exhaust flue products and piping to bring combustion air
to the water heater from outside, see Figure 21 & Figure
22 on Page 32.
In cold climates any water vapor remaining in the flue gases
will condense into a cloud of vapor at the point where the
vent system exits the building. Special consideration is
recommended, before locating the vent termination near
walkways, windows and building entrances.
Direct venting into dead spaces such as alleys, atriums,
and inside corners can cause recirculation of flue gases.
Recirculation of flue gases will cause sooting, and icing of the
combustion air intake during severe cold weather. To prevent
the recirculation of flue gases, maintain as much distance as
possible between the combustion air intake and the exhaust
vent terminal refer to Figure 16 and Figure 17 on Page 29 &
Page 30 respectively.
Approved vent and intake air pipe materials:
PVC pipe materials:
• DWV ASTM-D2665 or CSA B181.2
• Schedule 40, 80, 120 ASTM-D1785 or CSA B137.3
• SDR Series ASTM-2241 or CSA B137.3
CPVC pipe materials:
• CPVC 41 ASTM-D2846 or CSA B137.6
• Schedule 40, 80 ASTM-F441 or CSA B137.6
• SDR Series ASTM-F442
Polypropylene - See page 26
• M & G Duravent PolyPro vent system
• Centrotherm InnoFlue vent system
NOTE:
The use of cellular core PVC (ASTM F891), cellular core CPVC,
or Radel® (polyphenolsulfone) in non-metallic venting systems is
prohibited. Covering non-metallic vent pipe and fittings with thermal
insulation is prohibited.
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:
For water heaters in locations with high ambient
temperatures above 100°F (38°C) it is recommended that CPVC
or Polypropylene pipe and fittings be used.
All vent (exhaust) pipes must be pitched a minimum of a 1/4” per
foot back to the water heater to allow drainage of condensation.
Never operate the water heater unless it is vented to the outdoors.
The instructions in this section of the manual must be followed
to avoid choked combustion or recirculation of flue gases. Such
conditions cause sooting of the combustion chamber, burners and
flue tubes and creates a risk of asphyxiation.
For direct vent application where combustion air might be supplied
from extremely cold ambient through fresh air intake piping
system, it is recommended that a backflow preventer be installed
at the intake vent terminal close to the blower before proceeding
with installation of the rest of the fresh air intake piping. Call the
technical support phone number listed on the back cover of this
manual for more information.
VENTING INSTALLATION
Summary of Contents for 650HTPDT
Page 5: ...5 GENERAL SAFETY INFORMATION...
Page 58: ...58 NOTES...
Page 59: ...59 NOTES...
Page 60: ...60...
