Independence Installation, Operating, and Service Instructions

23
103538-08 - 3/18
Soutenez parties horizontales de ventilation pour
éviter l'affaisement. Utilisez des colliers de serrage,
des crochets on cintres espacées de 4 preds (1,2 m)
ou moins.
9. Vent pipe must be inserted into but not beyond
inside wall of chimney liner. Seal tight between vent
pipe and chimney.
E. If an Existing Boiler is Removed:
When an existing boiler is removed from a common
venting system, the common venting system is likely to
be too large for proper venting of the appliances
remaining connected to it.
At the time of removal of an existing boiler, the
following steps shall be followed with each appliance
remaining connected to the common venting system
placed in operation, while the other appliances
remaining connected to the common venting system are
not in operation:
1. Seal any unused openings in the common venting
system.
2. Visually inspect the venting system for proper size
and horizontal pitch and determine there is no
blockage or restriction, leakage, corrosion, and other
deciencies which could cause an unsafe condition.
3. Insofar as is practical, close all building doors and
windows and all doors between the space in which
the appliances remaining connected to the common
venting system are located and other spaces of the
building. Turn on clothes dryers and any appliance
not connected to the common venting system. Turn
on any exhaust fans, such as range-hoods and
bathroom exhausts, so they will operate at maxi mum
speed. Do not operate a summer exhaust fan. Close
replace dampers.
D. Install Vent Connector from draft hood or vent
damper to chimney. See Figure 27.
1. Do not connect into same leg of chimney serving an
open replace.
2. Vent pipe to chimney must not be smaller than outlet
on draft hood or vent damper. Type B is
recommended, but single-wall vent pipe may be
used. Arrange venting system so boiler is served by
vent damper device.
Exception: National Fuel Gas Code, ANSI
Z223.1/ NFPA 54, and Natural Gas and Propane
Installation Code, CAN/CSA B149.1, allow vent
downsizing when vent size determined by their
Vent Sizing Tables is smaller than draft hood
outlet/vent damper. These codes require all of
the following:
(a) Total vent height (H) is at least 10 ft (3 m);
(b) Vent not reduced more than one table size;
and
(c) Draft hood outlet/vent damper is greater
than 4 in. (102 mm) in diameter (IN3I
cannot use smaller vent size).
3. Where two or more appliances vent into a common
vent, the area of the common vent should be at least
equal to the area of the largest vent plus 50% of the
area in the additional vent(s).
4. Vent connectors serving appliances vented by
natural draft shall not be connected into any portion
of mechanical draft systems operating under positive
pressure.
5. Horizontal run should be as short as possible. The
maximum length of an uninsulated horizontal run
must not exceed 75% of the height of the chimney.
6. Vent pipe should have the greatest possible initial
rise above draft hood consistent with headroom
avail able and required clearance from adjacent
combus tible building structure. Vent pipe should be
installed above bottom of chimney to prevent
blockage.
7. Slope horizontal portions of vent pipe upwards not
less than 1/4 in/ft (21 mm/m) from boiler to vent
terminal.
les chaudiêres de catégories I doivent présenter des
tronçons horizontaux dont la pente montante est d'au
moins 1/4 po par pied (21 mm/m) entre la chaudiêre
et l'évent.
8. Support horizontal portions of venting system to
prevent sagging. Use pipe straps, brackets or
hangers spaced 4 ft (1.2 m) or less.
Figure 27: Typical Vent Installation
VII. Venting (continued)