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CAUTION
The vent shall terminate a minimum of 12 inches (30.5 cm) above expected snowfall level to prevent blockage of vent
termination.
The horizontal centerline of the exhaust vent terminal (if applicable) must not be located lower than the horizontal
centerline of the air intake terminal if vented through the same wall.
A service drain loop must be installed in the drain tubing to serve as a condensate trap to prevent flue gases from
escaping into the room.
DO NOT position the air intake above the exhaust terminal.
NEVER locate the air intake where exhaust gases can be introduced.
NOTICE
Before beginning installation of any vent pipe, read the vent pipe manufacturer’s installation instructions.
Do not install the water heater in any location where the ambient temperature may fall below freezing. Water heater
must be protected from freezing downdrafts during shutdown periods.
Provide protection of the building materials from degradation by flue gases from the exhaust vent terminal.
CAUTION
Check to make sure flue gases do not recirculate into the air intake terminal when using direct venting. If the water
heater is having service issues, flue recirculation may be a contributing factor. Even when the minimum vent terminal
separation distances are followed, recirculation may still occur depending upon the location outside the building, the
distance from other buildings, proximity to corners, weather conditions, wind patterns, and snow depth. Periodically
check to make sure that flue recirculation is not occurring. Signs of flue gas recirculation include frosted or frozen
intake terminals, condensate in the intake terminal and venting system, oxidation or white chalk material on the flame
sensor or igniter shield. Correction to flue recirculation may involve angling the intake away from the exhaust
terminal, increasing the distance between them, relocating the air intake to another side of the building, or using inside
air for combustion. Check to be sure the intake and exhaust terminals are not obstructed, especially during periods of
below freezing weather.
All intake and exhaust venting components must have the same diameter size. Do not use a different size on the
intake and exhaust venting. For 3 inch (7.6 cm) and 4 inch (10.2 cm) venting, use the supplied 2 inch (5.1 cm) vent
terminals.
Be sure the condensate runs freely to a drain and does not accumulate inside the water heater. In cold climates,
precautions may need to be taken to insure that the condensate drain does not freeze. Make sure the condensate trap
or drain loop is installed to prevent flue gases from being discharged into the room. Refer to the Venting section of
the Installation and Operating Instructions Manual for complete instructions on venting and condensate drainage.
High levels of dust and debris such as road and construction dust, insects, and tree pollen may clog the burner
resulting in poor performance and damage to the water heater. Avoid air intake locations where debris can be created
such as exhaust ventilation hoods, gravel parking lots, and near outdoor spotlights that attract bugs. For these
installations, an air intake filter kit, part number 239-47330-00A, is available as an accessory service part from the
installer of this water heater. The air intake filter kit is not designed to filter out airborne contaminants or chemicals
that may damage the water heater.