A.O. Smith BT-100-LP, Инструкция по эксплуатации

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19
The confined space shall be provided with two permanent
openings, one commencing within 12 inches (300 mm) of
the top and one commencing within 12 inches (300 mm)
of the bottom of the enclosure. See
Figure 17
.
Each opening shall communicate directly with an
additional room(s) of sufficient volume so that the
combined volume of all spaces meets the criteria for an
unconfined space.
Each opening shall have a minimum free area of 1
square inch per 1,000 Btu/hr (2200 mm
2
per kW) of the
aggregate input rating of all appliances installed in the
enclosure. Each opening shall not be less than 100
square inches (645 cm
2
).
VENTING
Water heaters covered by these instructions are Category
I, Natural Draft appliances.
If the water heater is being installed as a replacement
for an existing heater in pre-existing venting, a thorough
inspection of existing venting system must be performed
prior to any installation work.
VENT DAMPERS - Any vent damper, whether it is
operated thermally or otherwise must be removed if its
use inhibits proper drafting of the water heater.
Thermally Operated Vent Dampers: this gas-fired water
heater has a thermal efficiency at or above 80% which
may produce a relatively low flue gas temperature.
Such temperatures may not be high enough to properly
open thermally operated vent dampers. This would
cause spillage of the flue gases and may cause carbon
monoxide poisoning. Vent dampers must bear evidence
of certification as complying with the current edition of
the
American National Standard ANSI Z21.66 CGA 6.14
(covering electrically and mechanically actuated vent
dampers). Before installation of any vent damper, consult
the local gas utility for further information.
To insure proper venting of this gas-fired water heater,
the correct vent pipe diameter must be utilized. Any
additions or deletions of other gas appliances on a
common vent with this water heater may adversely affect
the operation of the water heater. Consult your gas
supplier if any such changes are planned.
For proper venting in certain installations, a larger
diameter vent pipe may be necessary. Consult your gas
supplier to aid you in determining the proper venting
for your water heater from the vent tables in the current
edition of the
National Fuel Gas Code ANSI Z223.1/NFPA 54
or the
Natural Gas and Propane Installation Code CAN\CSA
B 149.1
.
Periodically check the venting system for signs of
obstruction or deterioration and replace if needed.
The combustion and ventilation air flow must not be
obstructed.
The water heater with draft hood installed must be
connected to a chimney or listed vent pipe system,
which terminates to the outdoors. Never operate the
water heater unless it is vented to the outdoors and has
adequate air supply to avoid risks of improper operation,
explosion or asphyxiation.
• For proper draft hood attachment, the draft hood legs
may be angled slightly inward.
• Place the draft hood legs in the receiving holes on the
top of the water heater. The legs will snap in the holes
to give a tight fit. Secure draft hood with the supplied
brackets.
• Place the vent pipe over the draft hood. With the vent
pipe in position, drill a small hole through both the
vent pipe and draft hood. Secure them together with a
sheet metal screw. See
Figure 18
(page 20) .
Obstructed or deteriorated vent systems may present
serious health risk or asphyxiation.