Part Number 550-142-302/0520
CGi
SERIES 4 — GAS-FIRED WATER BOILER —
Boiler Manual
17
Venting — direct exhaust — termination
3e
Figure 12
Vent termination minimum clearances
Follow instructions on this page when determin-
ing vent location to avoid possibility of severe
personal injury, death or substantial property
damage.
1. Locate the boiler and vent penetration through the wall so
all requirements on this page and in Figure 12 will be met.
Also follow vent manufacturer’s instructions.
2. Gases will form white plume in winter. Plume could obstruct
window view.
3. Prevailing winds could cause freezing of condensate and wa-
ter/ice buildup on vent termination, building, plants or roof.
Ice buildup on vent termination can cause boiler shutdown
and building freeze up.
4. Winds over 31 mph can cause nuisance boiler shutdown if
boiler is sidewall vented. This could result in loss of heat to
building, causing freeze up.
5. Locate or guard vent termination to prevent condensate from
damaging exterior surfaces.
6. Locate the vent termination well away from trees, shrubs, and
decorative items.
7. Locate or guard vent to prevent accidental contact by people
or pets.
8. Do not terminate vent in window well, stairwell, alcove,
courtyard, or other recessed areas.
9. Do not wrap or insulate vent pipe or fittings.
10. Do not terminate vent above any door or window. Condensate
can freeze, causing ice formations.
11. Do not connect:
•
Any other appliance to vent pipe.
•
Multiple boilers to a common vent pipe.
The vent termination must be located to meet all requirements below (also applies to vertical vent terminations). The minimum
distance from adjacent public walkways, adjacent buildings, openable windows and building in the National Fuel Gas Code, ANSI
Z223.1/NFPA 54 – latest edition and/or the Natural Gas and Propane Installation Code, CAN/CSA B149.1. The vent termination
clearances below are for U.S.A., for Canadian vent termination clearances please refer to the requirements of CSA B149.1 Natural Gas
and Propane Installation Code. Consideration should be given to avoid possible damage caused by vent plumes and condensate when
choosing a venting configuration and location. Maintain a minimum clearance of 4 ft. (1.22m) horizontally from, and in no case above
or below, unless a 4 ft. (1.22m) horizontal distance is maintained, from electrical meters, gas meters, regulators, and relief equipment.
12. Canadian installations — See B149.1 or B149.2 Natural
Gas and Propane Installation Code. Terminate vent no less
than 6 feet from another combustion air inlet, 3 feet from
any other building opening, and 3 feet from any gas service
regulator.
13. See
Figure 12
, showing that the vent must terminate:
•
more than 4 feet below or to side of all doors or windows.
•
more than 1 foot above grade or anticipated snow line.
•
at least 7 feet above public walkway.
•
3 feet above any forced air intake within 10 feet.
14. Vent must also terminate:
•
at least 6 feet away from adjacent walls.
•
no closer than 5 feet below roof overhang.
•
at minimum of 4 feet horizontally (and in no case
above or below unless a 4 foot horizontal distance is
maintained) from electric meters, gas meters, regula-
tors, relief valves, and other equipment.
15. Site conditions may dictate greater clearances.
16. Do not extend exposed vent pipe outside of building more
than 4 feet.
Condensate could freeze and block vent pipe.
A gas vent extending through an exterior
wall shall not terminate adjacent to the wall
or below building extensions such as eaves,
parapets, balconies or decks. Failure to comply
could result in severe personal injury, death or
substantial property damage.
