Furnace Vent High Above Roof

The master flow 4 in.

Furnace vent high above roof.

The 1992 vent sizing tables require that all type b gas vents terminate above the roof with a listed cap or listed roof assembly in accordance with the manufacturer s instructions. So the gases can float up through the flue pipe and out of your roof. This vent is designed to be used on 4 in. Roof pitch is easily calculated and if you don t know how read my article understanding and calculating roof pitch.

High efficiency furnaces produce different combustion gases than standard efficiency furnaces. Goose neck vent in black can be used to cover exhaust pipes extending through your roof or for attic ventilation. Vents can also be terminated above the roof. How to vent a furnace in a roof.

Above the roof surface with a listed cap or listed roof assembly. Table of type b vent rooftop clearance requirements. The single pipe non direct vent system is used where there is no real need for a separate combustion air intake vent. When the vent is withdrawing air from the house it expels the gas outside through the vent.

What is vented is a residual corrosive condensate of water and carbon dioxide. If your furnace has an afue rating of 90 percent or above it will have a flue pipe that goes out of the side of your house. Goose neck vent the master flow 4 in. First you ll need to know the pitch of your roof.

All gas furnaces must be vented to allow exhaust gases from the combustion process to escape. A high efficiency condensing furnace can achieve efficiency ratings of 90 or above. Vent caps 12 and smaller may terminate a distance above the roof if 8 feet or more away from a vertical surface as follows. Gas vents 12 inches 305 mm in size or smaller with listed caps shall be permitted to be terminated in accordance with figure g2427 6 5 provided that such vents are at least 8 feet 2438 mm from a vertical wall or similar obstruction.

Vents must be tall enough so burned gases exit above a roof line and. Also known as the type b this vent is operating on the natural air convection. Also you ll need the horizontal distance between the peak and the edge of the high side of the pipe see figure 1 where you plan your roof penetration. While one foot above the roof surface may meet the recommendations for fire clearances in one storey buildings or in buildings with heating equipment on the uppermost floor the total chimney height may be inadquate to establish sufficient and safe draft unless you extend the chimney.

It provides a vent pipe for exhaust gases but uses unconditioned not cooled or heated air from the space around the furnace for combustion air. Notes to the table above 1 measure on the up roof or shorter height side of the chimney 2 watch out.