Install Instructions

43
APPENDIX B2 – DIRECT VENTING
Planning a Direct Vent System
1. Avoid contact with electrical wires and
plumbing.
2. Slope horizontal runs upwards not less than
¼ inch per foot from boiler to vent terminal.
3. Any condensate forming in the vent will
return to the boiler. Provide for a condensate
trap or siphon near the boiler to remove
condensate from the vent.
4. Support vent pipe to maintain vent location,
prevent sag and prevent accumulation of
condensate. The vent and/or air intake
piping must be adequately supported with
straps or supports with a maximum spacing
of ve (5) feet on horizontal runs.
5. Adhere to the boiler’s maximum and
minimum allowable vent lengths. Vent
length is provided in terms of equivalent
length of straight pipe plus equivalent length
of ttings, including both the vent and the
combustion air piping, but not including vent
or intake terminals.
6. Maintain minimum allowable clearances
between the vent pipe and combustible
materials as specied by the vent pipe
supplier, this manual, and applicable building
codes.
7. Do not install venting system components
on the exterior of the building except as
specically required by these instructions.
8. Locate the vent terminal per these
restrictions and Figure B-2:
(1) Minimum twelve (12) inches above
grade plus normally expected snow
accumulation level. Do not install over
public walkway or over an area where
appliance ue gas vapor or condensate
creates a nuisance or hazard or could
be detrimental to operation regulators,
relief valves or other equipment.
(2) Minimum three (3) feet above any
forced air intake located within ten (10)
feet.
Exception: Combustion air intake of
direct vent system.
(3) Minimum 4 ft. horizontally from, and in
no case above or below, unless a 4 ft.
horizontal distance is maintained, from
electric meters, gas meters, regulators
and relief equipment.
(4) Minimum twelve (12) inches from
overhangs or corners of buildings.
(5) If window and/or air inlet is within four
(4) feet of an inside corner, then vent
terminal must be at least six (6) feet
from adjoining wall of inside corner.
(6) Minimum one (1) foot below, one (1)
foot horizontally from, or one (1) foot
above any door, window, gravity air
inlet, or other air opening into building.
9. Locate the combustion air terminal on
the same face of the building as the vent
termination to prevent nuisance boiler
shutdowns.
GENERAL WARNINGS FOR DIRECT VENT SYSTEMS
DRAFT HOODS, VENT DAMPERS and other
obstructions or openings in the vent system are
prohibited.
DO NOT REDUCE THE DIAMETER of the vent
pipe.
MOISTURE AND ICE may collect around and
below the vent terminal. Keep the area in good
repair.
IF USING A CHIMNEY AS A CHASE for the vent,
do not vent any other appliance into the space
between the chimney wall and the vent.
ELIMINATE LOW SPOTS in the vent where ue
gas condensate may pool.
DO NOT PENETRATE VENT PIPE with holes or
fasteners.