Weil-McLain 550-141-829/1201 manual Connect Breeching, General chimney requirements

Connect Breeching

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

MINIMUM CHIMNEY SIZE TABLE

				MINIMUM
		* * *
		MINIMUM		I=B=R
BOILER
							MINIMUM
MODEL		BREECHING		CHIMNEY SIZE			CHIMNEY
NUMBER		DIAMETER		RECT.	ROUND		HEIGHT
SGO-3	5"		8" x 8"		6"	15'
SGO-4	6"		*
SGO-5	6"		8" x 8"		7"	15'
SGO-6	7"
			*
SGO-7
SGO-8	7"		8" x 12"		7"	20'
SGO-9			* *

*6¾" x 6¾" inside liner

** 6½" x 10½" inside liner

** * Flue collar on boiler is 7" diameter

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