8
VENTING SYSTEM INSPECTION & INSTALLATION
RIDGE
2’ (.61 M) MIN.
MORE THAN 10’ (3.1 M)
10’ (3.1 M)
HEIGHT ABOVE ANY
ROOF SURFACE WITHIN
10’ (3.1 M)
HORIZONTALLY
CHIMNEY 3’ (.92 M)
GAS VENT OR
TYPE L VENT
2’ (.61 M) MIN.
If oil fired water heater is vented into same flue as boiler,
provide separate hole into chimney whenever possible.
When this isn’t possible, use “Y” connection in flue pipe,
using separate draft regulator for each unit. When chimney
will not provide adequate draft to handle input from water
heater and boiler simultaneously, wire units so only one will
operate at a time, favoring water heater.
OIL TANk AND PIPING
Oil tank and piping should be installed in accordance with
National Board of Fire Underwriters and local regulations.
Oil storage tank, vent, fill pipe and caps should be as
prescribed by local codes. In no case should vent pipe be
smaller than 1¼" I.P.S. Fill pipe should not be less than 2"
I.P.S.
Ssuction line from tank to burner should be one continuous
piece of tubing to prevent air entering line. Suction line,
must be ⅜" O.D. copper tubing for runs of 50 feet or less,
and ½" O.D. for longer runs. Oil return line, same size as
suction line, must be used on any installation where bottom
of tank is below fuel unit of burner. Oil lines should be
buried or otherwise protected from mechanical injury. Flare
fittings on all oil lines are recommended. Compression
fittings on suction line often allow air to be drawn into fuel
pump, making it difficult to maintain oil pressure at nozzle.
Do not run overhead fuel lines from tank to oil burner.
!
WARNING
Boiler is to be vented by natural draft and
shall not be connected into any portion of
mechanical draft operating system under
positive pressure.
Inspect chimney to make certain it is constructed according
to the latest revision of the NFPA 211. Local regulations
may differ from this code and should be checked. Where
there is a conflict, the local code will prevail.
The boiler must be installed into a chimney which has a
masonry or metallic chimney liner.
An unlined chimney will have leaks that will cause poor
chimney performance (no draft), and could result in a
positive pressure in the combustion chamber.
Horizontal portions of the venting system should not exceed
10 feet in length. Horizontal lengths over 10 ft. will have a
negative effect on the chimney performance.
The chimney should extend at least 2 ft. above any portion
of the building within 10 ft.
(Figure #11)
It should produce
a -.02 inch W.C. draft in the combustion chamber. See
"Chimney or Vent Sizes" chart for recommended minimum
and maximum chimney or vent sizes.
Inadequate draft will cause improper combustion, resulting
in dirty flue ways and high fuel bills.
Connect flue pipe same size as boiler outlet to chimney,
sloping upward continuously toward the chimney
approximately ¼" per foot. Bolt or screw joints together to
avoid sag.
CHIMNEY OR vENt SIZES
BtU/HR INPUt
ROUND
INCHES
SQUaRE
INCHES
HEIGHt (Ft)
MIN
MaX
MIN
MaX
MIN
MaX
91,000 - 140,000
6
8
8x8
8x8
15
40
175,000 - 210,000
7
8
8x8 8x10
15
40
245,000 - 280,000
8
10
8x8 8x12
15
50
315,000
8
10
8x8 8x12
15
50
385,000
8
10
8x8 8x12
15
50
Figure #11
