Chimneys and Chimney Troubleshooting
The chimney used with an oil-fired furnace should be of sufficient height and large enough in its cross-sectional area to meet the requirements of the furnace. The chimney area should be at least 20 percent greater than the area of the flue outlet. To ensure the adequate removal of flue gases, the height and size of the chimney must be sufficient to create 0.02 to 0.04 in wg draft over the fire for inputs up to 2.0 gph. For higher inputs, 0.06 to 0.08 in wg is rec- ommended. If the stack height is limited, it may be necessary to apply mechanically induced draft to the installation.
Ideally, only the furnace should be connected to the chimney. Read the section Chimneys in Chapter 11, “Gas Furnaces” for additional information. See also Chapter 3, “Fireplaces, Stoves, and Chimneys” in Volume 3 for additional information about chimneys.
Read the section Chimney Troubleshooting in Chapter 11, “Gas Furnaces” for a description of common chimney problems and suggested remedies. The chimneys used with oil-fired furnaces are identical to those used with gas furnaces. Additional information about chimney and flues is covered in Chapter 3, “Fireplaces, Stoves, and Chimneys” of Volume 3.