Bradford White 120T400, Руководство по установке и эксплуатации

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VENTING
The venting instructions must be followed to avoid restricted combustion or recirculation of flue gases. Such
conditions cause sooting or risks of fire and asphyxiation.
This water heater can be installed as either a power direct vent system or power vent (air from inside) system. If it is
installed as a direct vent system, then the air intake and the exhaust vent are piped to the outside. If a power vented
system is used, then air is drawn from inside and only the exhaust is piped to the outside. Determine which system is
best for your application and install as described in the following sections.
VENT INTAKE/EXHAUST TERMINALS
This water heater is supplied with a 4 inch (10.2 cm) diameter screened intake elbow and exhaust coupling referred to
as the air intake terminal and the exhaust vent terminal. These 4 inch supplied vent terminals can be used with 4 inch
venting. When venting with 6 inch (15.2 cm) venting is desired, please discard 4 inch vent terminals and use field
supplied 6inch fittings instead. It is recommended to use a galvanized ¼”x1/4” square opening screen cut to a 7 ½”
diameter circle. Then insert the screen into the field supplied intake/exhaust terminals.
POWER DIRECT VENT INSTALLATION
Venting may be run horizontally through an outside wall or vertically through a roof through using either 4 inch
(10.2
cm)
or 6 inch (15.2 cm) diameter pipe. This water heater is supplied with a screened intake elbow and exhaust
coupling referred to as the air intake terminal and the exhaust vent terminal.
Power Direct Vent Terminal Location
Plan the vent system layout so that proper clearances are maintained from plumbing and wiring. Before the vent is
installed, determine the vent pipe termination location as shown in Figure 11.
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 spark rod. 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 4 inch venting, use the supplied 4 inch vent terminals. For 6 inch venting see the terminal section.
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 ensure 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
Operation 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.
CAUTION
The vent shall terminate a minimum of 12 inches 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
The air intake and exhaust terminals may be located on separate outside walls or one terminal may exit the roof while
the other is through the wall. The total combined equivalent vent length must be within the limits specified in the venting
tables and the intake length cannot exceed the exhaust by more than 30 feet. The minimum recommended vent
separation distance between the intake and exhaust terminals is 36”. Local conditions may require a need for greater
vent separation distances.
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