Harman Stove Company MARK I Venting & Chimneys, Types of Chimneys, Common chimney problems

Venting

Where an existing chimney is used, it must be large enough to provide a draft adequate for removing the gaseous products of combustion. The cross-sectional area of the chimney must be at least 25 percent greater than that of the connector. As a general rule, common 8” X 8” flue liner has an actual interior cross-sectional area of 42 to 49 inches. This is adequate for a 6 inch stove connector, which matches the appliance flue collar.

Important! The connector pipe must be constructed of 24 gauge material or thicker.

3. Venting & Chimneys:

3.1 TYPES OF CHIMNEYS

The chimney is one of the most important, yet the most neglected and misunderstood portion of any solid fuel burning appliance installation. Do not connect your stove to a chimney flue that already serves another heating device.

The stove must be connected to its own flue. A minimum 8” X 8” is necessary for proper operation.

Under no circumstances should a manual flue damper be installed in the smoke pipe between the stove and the chimney.

Caution! the chimney must be a “class A” chimney in good working condition. the use of aluminum “type b” gas vent for solid fuels is not only un-safe but it is prohibited by the national fire protection agency (nfpa) code.

There are three types of “Class A” chimneys;

1)Masonry with a tile liner, including brick, block, stone, etc. It must be supported by a ground-level foundation.

2)Insulated “Class A” manufactured chimney, listed and certified by a national test agency.

3)Triple-walled metal “Class A” chimney, listed and certified by a national test agency.

If your masonry chimney has not been used for some time, have it inspected by a qualified person (building inspector, fire department personnel, etc.). If a listed and certified manufactured chimney is to be used, make certain it is installed in accordance with the manufacturers instructions and all local codes.

A coal stove can perform only as well as its venting system will allow it to.

3.2 common chimney problems

In order to have a properly operating heating system, the chimney needs to be capable of providing sufficient draft. The minimum required draft is .06 inches of water column (WC). To measure the draft, drill a hole in the connector pipe and attach a draft meter. First, check the draft above the barometric damper (if installed). Then check it below the barometric damper and make your damper adjustment to where it opens to prevent the draft from going higher than the .06 in WC. If the chimney is incapable of supplying the necessary draft, it will need to be improved. Whether it needs to be raised to a taller height, a flue liner installed, or a different style of cap placed on the top, the improvement method will need to be determined.

Reasons for insufficient draft;

A)Leaking chimney- Air leaking in around a loose fitting cleanout door, joints or seams in connector pipe are not secured properly, cracks or other defects in masonry.

B)Improper chimney height - Chimney does not extend to a sufficient height above the roof line. (Remember the 3 ft.-2 ft.-10 ft. rule)

C)Obstructions in the chimney - Make sure the chimney has been cleaned. Different animals have been known to build nests in chimneys.

D)Trees or other topographical barriers - Trees that are taller than the house can cause the air currents to flow downward over the peak of the roof. This would lead to a down draft effect on the chimney. This can also be caused by adjacent buildings or fixtures. It could even be from a different peak on the same structure.

Wind direction

7 Magnafire Series Coal Stoves 3-90-70746R8_11/12