Typical Methods Of Safely Venting The Heater - Williams 3501522A Owner's Manual

INSTALLING YOUR HEATER
3. Use vent pipe of the same size as the outlet on back
of heater. In no case should a different size vent
be used. Single wall vent pipe may be attached
directly to the draft hood of the room heater when a
clearance of 3 inches (76.2 mm) is maintained
between the single wall vent pipe and the
combustible wall of the room in which the room heater
is located. Use double wall vent pipe for clearances less
than 3 inches (76.2 mm) to combustibles.
4. Avoid a horizontal run to the vent pipe whenever
possible. When a horizontal run is necessary, the pipe
must pitch upward at least 1/4 inch per foot. It must be
supported securely and joints fastened by sheet
metal screws or rivets. Under no circumstances should
the vent run downhill.
5. Never put a damper or barometric draft control in a
gas vent pipe.
6. Never end a vent in an open attic or run a vent
through a wall to the outside without extending it
upward above the roof.
7. Always terminate the vent with an approved vent cap.
8. ALWAYS SECURE THE VENT PIPE TO THE OUTLET
ON THE BACK OF THE HEATER WITH A SHEET
METAL SCREW.
9. The flue pipe should extend through the wall of a
chimney to be flush with the inner wall.
10. The flue pipe must be adequately supported by
metal strips.
11. For the flue pipe running through walls and roofs,
use B type (1 inch (25mm) clearance to combustibles)
vent pipe.
12. Vents should extend at least 2 feet (.6m) above the
roof and above any object or nearby building within
10 feet (3m).
13. Open tees should not be used in the flue pipe.
14. The heater must not be connected to a chimney flue
that is servicing a separate solid-fuel burning appliance.
15. Run flue pipe as direct as possible with not more than
two elbows. Use 45 degree elbows if possible
16. The use of more than one appliance per vent system
may cause the vent safety shutoff device to shut
off the heater due to the cooling of vent temperatures
through the draft diverter of the second appliance.
17. The vent safety shutoff may shut down the heater if
a too large or an unlined, masonry chimney is
used. The vent may not warm quickly enough to get
adequate vent action in a chimney before the shutoff
device will shut down the heater. If this is the case, it is
recommended lining the chimney with proper size
type "B" vent pipe or type "B" chimney liner.
18. Single-wall metal pipe should not be used outdoors
in cold climates or venting gas equipment. If the vent
is installed directly outside, the cold pipe may delay
the venting and cause the heater to shut-off by the
vent safety switch. To prevent this problem, as well
as condensation of flue products, an insulated
14
VENTED ROOM HEATERS
enclosure is recommended. Use type B, vent pipe and
maintain at least a one inch clearance to combustibles.
Use a metal thimble to protect vent pipe as it passes
through combustibles.
IMPORTANT: Inspect venting system prior to each
heating season.
Typical Methods of Safely Venting
Your Heater
1. Any horizontal run of vent pipe must slope upward a
minimum of 1/4" per foot. Secure all joints of the vent
with sheet metal screws.
2. Where the vent passes through the ceiling or wall, a
thimble is required to keep the ceiling from catching
fire. Use only a thimble designed for use with Type "B"
gas vent, certified by a nationally recognized testing
agency.
3. The vertical (straight up and down) part of the vent
must end 2 feet above any part of the roof within 10 feet
of the vent. This is to make sure the "draw" of the vent
is not obstructed in any way.
4. A vent cap, approved by a nationally recognized
testing agency, must be installed on top of the vent to
keep out rain and snow and to prevent obstructions of
the vent. The vent cap will also prevent excessive
downdraft that can cause carbon monoxide to enter
into the home. Do not use a homemade vent cap.
They are dangerous and can restrict the draft of the vent.
5. Safe clearances are shown below. To prevent a fire,
make sure the heater is installed no closer than the
distances shown in the figures that apply to your type
of venting.
6. If you are venting into a masonry chimney, it must be
lined, in good repair and must not serve a wood or
coal burning appliance. The flue must be at least as
large in diameter as the vent connector. The top of
the chimney must be two (2) feet higher above
any part of the roof within ten (10) feet horizontally
of the chimney and must be three (3) feet higher than
the point where it passes through the roof line. If
installed in front of a fireplace, the pipe must pass
through a sheet metal cover on the fireplace that fits tightly.
VENTED ROOM HEATERS VENT SIZE (INCHES)
NATURAL GAS PROPANE GAS
2001622A
350522A
5001522A
6501522A
3502522A
5002522A
6502522A
VENT SIZE (INCHES)
2001621A 3
3501521A 4
5001521A 4
6501521A 5
3502521A 4
5002521A 4
6502521A 5