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BRADFORD WHITE
Page 6
B4 Volume Water Heater Page 7
3. Avoid using long horizontal runs of the vent
pipe, and too many 90° elbows, reductions or
restrictions. Horizontal runs should have at least
a 1/4" rise per foot in the direction of ow. A vent
connector should be supported for the design
and weight of the material used to maintain
clearances and prevent physical damage and
separation of joints.
4. Avoid ending heater vents near air conditioning
or air supply fans. The fans can pick up exhaust
ue products from the heater and return them
inside the building, creating a possible health
hazard. A minimum of 4 feet horizontal distance
must be maintained from electrical meters, gas
meters, and relief equipment.
5. Always use double-wall or insulated vent
pipe (Type B or equivalent). In cold weather,
uninsulated outside vents can chill the rising ue
products, blocking the natural draft action of the
venting system. This can create a health hazard
by spilling ue products into the heater room.
6. Avoid oversize vent piping or extremely long
runs of the pipe which may cause excessive
cooling and condensation. Rule of Thumb: The
total length of the vent, including the connector
and any offset, should not exceed 15 feet for
every inch of vent diameter. Longer total lengths
shown in venting tables are based on maximum
capacity, not condensation factors.
7. When the installation of a draft fan is necessary
in connecting a venting system to a the heater,
the installation should be engineered by
competent personnel following good engineering
practices. The draft fan supplier should be
consulted for correct size. The installation
should be in accordance with the latest edition
of ANSI Z223.1 and/or, in Canada, CSA
B149.1 requirement and any local codes having
jurisdiction. When a draft fan is installed, a
suitable draft switch must be wired into the
heater control circuit at terminal designated
“Field Interlock” to prevent ring of the heater
unless a positive draft has been established.
2.3 Installation of Outdoor Heaters
1. Locate the heater to provide the minimum
clearances as listed in Table 1, “Placement of
Heater”.
2. Do not place the heater in an enclosure or wall
recess. Avoid locations where wind deection off
structures might cause down draft. When such
wind conditions are possible, place the heater at
least three (3) feet from the structures.
3. Never install the heater under any kind of roof
overhang. Do not place the heater below or
adjacent to any doors, windows, louvers, grills,
Figure 7. Incorrect Outdoor Installation.
etc. which connect in any way with an inhabited
area of a building. This includes other structures
such as garages or utility rooms (see Figure 7).
4. Although these models are CSA designed
certied for outdoor installations, such
installations are not recommended in areas
where the danger of freezing exists unless proper
precautions are taken for freeze protection.
2.4 Gas Supply and Piping
Review the following instructions before
proceeding with the installation.
1. Verify that the heater is tted for the proper type
of gas by checking the rating plate. Bradford
White heaters are normally equipped to operate
below a 2000 foot altitude. Heaters equipped
to operate at higher altitudes have appropriate
stickers or tags attached.
Table 3. Gas Piping Sizes.
Note: These gures are for Natural Gas (.65 Sp. Gr.), and are
based on 1/2" water column pressure drop. Check supply pres-
sure with a manometer, and local code requirements for varia-
tions. For LPG, reduce pipe diameter one size, but maintain a 1"
minimum diameter. A normal number of Tees and elbows have
been taken into allowance.