Water Heater Installation; Planning The Vent System - A.O. Smith 100 Series Installation And Operating Manual

PLANNING THE VENT SYSTEM

This water heater may be installed in either a Power Direct Vent
(PDV) or in a Power Vent (PV) configuration. Both configurations
must be properly vented for removal of exhaust gases to the outside
atmosphere. Correct installation of the vent pipe system is mandatory
for the safe and efficient operation of this water heater and is an
important factor in the life of the unit.
This water heater, when installed in a PDV configuration, has a direct
vent system in which all combustion products (exhaust) must be
vented to the outdoors and will require outdoor air for combustion.
Both intake and exhaust piping will require a sealed piping system
as described in these instructions.
When installed in a Power Vent (PV) configuration, this water heater
will require room air for combustion. Adequate air intake resources
are required. The exhaust piping will require a sealed piping system
as described in these instructions.
CAUTION
Improper Installation, use and service may result
in property damage.
This unit includes an air intake terminal
and an exhaust vent terminal.
WARNING
Breathing Hazard - Carbon Monoxide Gas
• Install vent system In accordance with codes.
• Do not operate water heater if flood damaged.
• Install water heater in accordance with the
instruction manual.
• Do not operate if soot buildup is present.
• Do not obstruct water heater air intake(s) with
insulating jacket or blanket.
• Do not place chemical vapor emitting products near
water heater.
• Gas and carbon monoxide detectors are available.
• Never operate the heater unless it is vented to the
outdoors and has adequate air supply to avoid risks
of improper operation, fire, explosion or asphyxia-
tion.
• Analyze the entire vent system to make sure that
condensate will not become trapped in a section of
vent pipe and therefore reduce the open cross
sectional area of the vent.
Breathing carbon monoxide can cause brain damage or death.
Always read and understand instruction manual.
Table 4 and Table 5 (page 15) list the allowable vent materials. Figure
27, Figure 28, and Figure 29 (page 23) show various end termination
details and clearances for PDV installations. Figure 31, Figure 32, and
Figure 33 (page 27) shows various end termination details and
clearances for PV installations

WATER HEATER INSTALLATION

WATER HEATER INSTALLATION
Note: The information provided in Figure 2 (page 8) is intended
as a guideline for good vent installation practices only.
This water heater may be vented horizontally through a wall or
vertically through the roof. Pipe runs must be adequately supported
along both vertical and horizontal runs according to local codes or
the venting manufacturer's instructions such as IPEX (www.ipexna.
com/resources/technical-library).
Note: Do not use an elbow as a support point. Elbows are not
designed to carry the load or stresses of the venting system
if they are rigidly held.
Note: Do not use the condensation trap as a support point. It not
designed to carry the load or stresses of the venting system.
Vent piping must be supported adequately and not put any
weight on the condensation trap.
Vent pipe must be installed in accordance with all local codes or,
in the absence of such, the latest edition of Natural Gas and Propane
Installation Code B149.1. In addition, clearances from combustible
materials must be provided in accordance with information in the
"Locating The New Water Heater" section of this manual. Take
note of the clearance and venting requirements when installing in a
confined space such as a small room or closet. Vent pipes serving
power vented appliances are classified by building codes as "vent
connectors".
• Plan the vent system layout so that proper clearances are
maintained from plumbing and wiring.
• Plan the layout of the vent system from the vent termination to
the water heater considering all the elbows (90° and 45°) plus
the number of feet of pipe that will be needed to install the total
vent system.
• Venting should be as direct as possible with the fewest number
of fittings.
• Use long radius 45° and long radius 90° elbows wherever
possible.
• Avoid using 90° elbows "back to back" and do not use street
elbows.
• Maintain a minimum 150 mm (6") straight section between
elbows. Closely coupled and short radius elbows reduce
the venting capacity. Figure 12 shows examples of vent pipe
connections.
WARNING
Breathing Hazard - Carbon Monoxide Gas
• Install water heater in accordance with the
instruction manual and B149.1.
• To avoid injury, combustion and ventilation air
must be taken from outdoors.
• Do not place chemical vapour emitting products
near water heater.
Breathing carbon monoxide can cause brain damage or death.
Always read and understand instruction manual.
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