10
Part Number 550-142-785/0812
GWI
Series 2
Gas-Fired Water Boilers –
Boiler Manual
Direct exhaust venting
continued
1. Locate the boiler and vent penetration through the wall so all
requirements on this page and in
Figures 4 and 5 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
water/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, court-
yard, 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.
12. Canadian installations — See B149.1 or B149.2 Installation
Code. Terminate vent no less than 6 feet from another com
-
bustion air inlet, 3 feet from any other building opening, and
3 feet from any gas service regulator.
13. See Figures 4 and 5, showing that the vent must terminate:
• at least 7 feet above public walkway.
• 3 feet above any forced air intake within 10 feet.
• more than 4 feet below or to side of all doors or windows.
• more than 1 foot above grade or anticipated snow line.
14. Vent must also terminate:
• at least 6 feet away from adjacent walls.
• no closer than 5 feet below roof overhang.
• at least 4 feet horizontally (and in no case above or below
unless a 4 foot horizontal distance is maintained) from
electric meters, gas meters, regulators, relief valves, and
other equipment.
15. Site conditions may dictate greater clearances.
16. Do not extend exposed vent pipe outside of building. Conden
-
sate 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, overhangs, balconies or
decks. Failure to comply could result in severe per
-
sonal injury, death or substantial property damage.
Vent termination location
Follow instructions on this page when determining
vent location to avoid possibility of severe personal
injury, death or substantial property damage.
Figure 4
Maintain minimum clearances from public
walkways and building air openings
Figure 5
Maintain minimum clearances from doors,
windows and snow line
3 Vent installation
continued
