B-Vent is intended for neutral or negative draft applications. It is designed for vertical installations (including laterals) but may be used for horizontal applications with a draft-inducing fan located such that all indoor portions of the vent are under negative pressure.
No. Per the sizing tables, all orientations must terminate vertically with a UL listed rain cap, otherwise the appliance may not vent properly.
While you can indeed run a horizontal vent pipe, you can't do it indefinitely; this is designed to provide your pipes with the ability to drain into the sewer system. The typical rule of thumb according to code requires you to run a horizontal pipe for no more than one-third of the total length.
905.3. 1 Horizontal Vent
A horizontal vent that is less than six inches in height above the flood level rim of the fixture being served must be served with a clean out.
Maintain a pitch or rise from the appliance to the vent cap on horizontal runs. The pitch shall not be less than ¼ inch to the foot.
Type B vents must be equipped with their own special chimney caps. If the cap is damaged or lost, it should not be substituted with something not recommended by the manufacturer. The clearance required from combustible materials is printed on the flue's exterior metal surface, and is generally 1 or 2 inches.
If you have 1 ¼-inch pipe, the horizontal distance of the vent should not be more than 30 inches. For a 1 ½-inc pipe the vent should be 42 inches away at the most while a 2-inch pipe must have a maximum distance of 5 feet.
Appliances designed for natural draft venting and incorporating integral venting means shall be located so that a minimum clearance of 9 inches (229 mm) is maintained between vent terminals and from any openings through which combustion products enter the building.
Not to exceed one-third of the total permitted length of a vent shall be permitted to be installed in a horizontal position.
Type B Vent shall not be used to vent flue products from incinerators, combination gas/ oil appliances, oil-fired, or wood-burning appliances. If there is a question about the use of Type B Vents, contact the appliance manufacturer or DuraVent's Engineering Department for further information. 1. Appliances.
The slope of the vent section of the horizontal branch drain shall be not greater than 1 unit vertical in 12 units horizontal (8-percent slope).
STUDOR AAVs must be installed in the vertical, upright position. A maximum deviation (in either direction) of 15 degrees is allowed. The vent shall connect to the drain vertically to maintain an unobstructed opening in the piping to the STUDOR AAVs.
Vent pipes must be installed so they stay dry. This means that they should emerge from the top of the drainpipe, either straight vertically or at no less than a 45-degree angle from horizontal, so that water cannot back up into them.
Type B Gas Vent Systems Give You These Important Advantages
Safety of the Hart & Cooley® system is assured by the double-wall, air-insulated design and locking joints. Properly installed, the vent cannot come apart through vibration, and offers protection against vent failure or fire hazard.
B-vent is ONLY allowed on Category 1 appliances unless the appliance manufacturer has specifically certified a particular B-vent system to be used alternatively.
Gas Vent Connectors
Double-wall corrugated aluminum with B vent ends can be used anywhere B vent is used, except where it passes through walls, floors, ceilings, and inside enclosures.
The maximum horizontal length of a Type B double-wall connector shall be 100 percent of the height of the chimney or vent except for engineered systems.
No more than four water closets or bathroom groups shall be installed on a 3" horizontal fixture branch. EXCEPTION: Where the water closets are rated 3.5 gallons or more per flush, no more than two water closets or bathroom groups shall be permitted.
THE MINIMUM CLEARANCE OF 1 INCH FROM THE VENT PIPE SURFACE. In multi-story buildings, a firestop must be provided at every point where the vent p asses through a floor or ceiling.
Drywall and wallboard are considered combustible materials and should not be installed against the vent including the use of this material to close off the hole around the vent. Type B Gas Vent requires a minimum of one-inch clearance to combustibles.
All unused openings in a gas vent must be sealed to prevent loss of effective vent action. Firestop Spacer/ Support Plate Firestop Spacer placed on top of floor or framed opening. and maintained. All Type B Gas Vents passing through floors, ceilings or walls must be firestopped using the Firestop Spacer as per Fig.
Check the slope of the B-vent pipe: The pipe should be installed with an upward slope of at least 1/4 inch per foot to ensure that developing condensate and flue gases can flow through the pipe. If the pipe isn't sloped correctly, it may cause air to become trapped and block airflow.
As a general rule, a flue should work effectively when it's up to 10 metres in length. This is usually based on a standard thickness of 60/100mm. For flues that need to be longer than this, it's a good idea to increase the thickness to 80/125mm to ensure that the gases are able to escape easily.