Weil-McLain 550-141-829/1201 - Manual (Page 12)

General chimney requirements:
• Designed for natural draft firing. Connect
boiler to vertical chimney.
Insufficient draft can cause flue
gas leakage and carbon
monoxide emissions, which will lead to severe
personal injury or death.
• Use vent material approved by local codes for
oil-fired burners. In their absence, refer to:
— NFPA 31, Installation of Oil-Burning Equipment.
— NFPA 211, Standard for Chimneys,
Fireplaces, Vents and Solid Fuel
Burning Appliances.
— In Canada, refer to CSA B139, Installation
Code for Oil-Burning Equipment.
• NFPA 211 requires chimney to be lined before
connected to boiler.
Inspect existing chimney before
installing new boiler. Failure to
do any of the following will result in severe
personal injury or death:
— Clean chimney, including removal of blockage.
— Repair or replace damaged pipe or liner.
— Repair mortar and joints.
To prevent downdrafts, extend chimney at
least 3 feet above highest point where it passes
through roof and 2 feet higher than any
portion of building within 10 feet. Increase
chimney cross-sectional area and height at
least 4% per 1,000 feet above sea level.
• Minimum clearances from vent pipe to
combustible material:
6 inches — Type “L” doublewall vent
18 inches — Singlewall vent
• Minimum chimney sizes should be used.
Oversized chimneys, outside
masonry chimneys and/or
derated inputs can result in condensation
in chimney.
Connect breeching:
Long horizontal breechings,
excessive number of tees and
elbows, or other obstructions restricting combustion
gas flow can result in possibility of condensation,
flue gas leakage and carbon monoxide emissions,
which can lead to severe personal injury or death.
1. Install 2 flue pipe brackets.
2. Connect full-sized breeching when possible.
See Minimum Chimney Size Table.
— Back outlet — see FIGURE 7.
— Top outlet — see FIGURE 8.
3. Connection must be made above bottom of
chimney to avoid blockage. Breeching must not
enter chimney far enough to cause obstruction.
Use thimble or slip joint where breeching enters
chimney to allow removal for cleaning.
4. When burner and boiler are properly installed,
draft overfire will be approximately -0.01"
to -0.02" W.C. Install barometric control in
breeching, per control manufacturer's
instructions, when excess draft needs to be
relieved or to comply with applicable codes
and regulations. Use draft gauge to adjust
proper opening.
5. An induced draft fan for the chimney may be
necessary if:
— Excessive resistance to flow of combustion
gases can be expected.
— Cross-sectional area of chimney is smaller
than minimum recommended.
— Chimney height is less than recommended.
Seal all vent joints. Interlock burner with
fan operation.
12
Connect Breeching
MINIMUM CHIMNEY SIZE TABLE
SGO-3 5"
8" x 8" 6" 15'
SGO-4 6" *
SGO-5 6"
SGO-6
7"
8" x 8" 7" 15'
SGO-7
*
SGO-8
7" 8" x 12" 7" 20'
SGO-9 * *
BOILER
MODEL
NUMBER
* * *
MINIMUM
BREECHING
DIAMETER
MINIMUM
I=B=R
CHIMNEY SIZE
RECT. ROUND
MINIMUM
CHIMNEY
HEIGHT
* 6¾" x 6¾" inside liner
* * 6½" x 10½" inside liner
* * * Flue collar on boiler is 7" diameter