Vermont Casting 2310 Chimney Guidelines, New Chimneys, Existing Chimneys, 2000898

Weak draft situations are characterized by smoking and odor problems in the house, low heat output, and difficulty maintaining a fire, especially at low thermostat settings. The reverse situation, overdraft, is rare, but can be recognized by short burn time, poor response when trying to slow down the fire, or by any part of the stove glowing red.

A more common cause of overdraft is inadequate maintenance, such as worn gasket allowing uncon- trolled air to enter the stove. Following recommended maintenance procedures will ensure consistent stove performance.

Following the stove manufacturer’s recommendation on both chimney size and height will also help ensure ad- equate chimney flow capacity. Flow capacity measures the ability of the chimney to evacuate combustion gas- es quickly. Even the strongest draft cannot overcome an insufficient flow capacity; the result is a back up of combustion gases in the chimney which forces smoke out of chimney connector joints or the stove itself. Re- member, the Vigilant and the chimney must function as a unit. For optimum performance, they must be sized properly for each other. Your Vermont Castings Autho- rized Dealer can help you assess your existing chimney

or plan a new one for best stove operation.

Chimney Guidelines

DO NOT CONNECT TO ANY AIR DISTRIBU- TION DUCT OR SYSTEM.

New Chimneys

Both masonry and prefabricated metal chimneys work well.

Prefabricated Double- wall Insulated Chimney

Tile-lined

Masonry

Chimney

ST241

Fig. 2 Chimney types.

A new masonry chimney should be constructed to con- form to the standards of your local building code or a recognized national code. Masonry chimneys must be lined with code-approved masonry or pre-cast refrac- tory tiles, stainless steel pipe suitable for use with coal, or a code-approved poured-in-place liner. The chimney must have a tight sealing clean-out door.

Vermont Castings Vigilant

A new prefabricated metal chimney should be one test- ed and listed for use with solid-fuel burning appliances to the High-Temperature (H.T.) Chimney Standard UL- 103-1985 (2100° F.) and have interior walls especially designed for use with coal-burning stoves. Be sure to follow the chimney manufacturer’s instructions exactly when passing the chimney through a combustible wall or ceiling. Special accessories may be necessary for this type of installation.

The chimney should extend at least 3 feet above the highest point where it passes through a roof, and at least 2 feet higher than any portion of a building within

10 feet.

	0 To 10'
	2' Min. 3'	0 To 10'
	Min.
		2' Min. 3'
		Min.
	Reference	AC617
	Point
Fig. 3	The 2’-3’-10’ chimney rule.

For proper draft and good performance, any chimney used with a Vermont Castings wood or coal burning stove should extend at least 16 feet above the flue col-

lar of the stove.

Existing Chimneys

An existing masonry chimney may work well, but be sure to have it carefully inspected before using it. De- fects may have gone unnoticed if the chimney previ- ously was used only occasionally. Defects must be repaired before the chimney is used with your stove. If you are not sure that you can make the inspection yourself, your local professional chimney sweep, build- ing inspector, or fire inspector will be able to make the inspection or direct you to someone who can.

The chimney should be thoroughly cleaned before be- ing used with your stove.

First, check to see that the chimney has a lining. Do not use an unlined chimney. Your local Vermont Cast- ings Authorized Dealer or chimney sweep can help you with information about approved chimney lining systems. In addition, look for and repair (if necessary) these defects: (Fig. 4)

A.Improper chimney height and roof clearance; check local building codes for proper construction.

B.Chimney cap deterioration; rebuild.

C.Creosote stains indicate flue damage; inspect and repair.

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