Installation instructions
3.6Venting 
Danger: Do not reduce the vent pipe size. Do not put an elbow directly on top of heater. Failure to follow venting requirements may cause dangerous exhaust gases to enter living space.
BMinimum vent pipe diameter: 5 inches
BMinimum vertical vent height: 6 feet, with no elbows
BEstablish 12 inch rise before any elbow
The heater must be vented to the outside following all local ordinances and specifications for installing a gas appliance vent or chimney. The heater must be located as close as practicable to a vertically rising chimney or vent that has a listed vent cap at its termination point. The venting system must be designed and constructed so as to develop a positive flow adequate to remove flue gasses to the outdoors. Consult the National Fuel Gas Code if the vent will have elbows or share venting with another natural draft appliance.
Warning: Do not combination vent with a mechanically vented appliance.
3.6.1Horizontal venting
Warning: Horizontally venting to a vertically constructed vent stack along an outside wall of a building is not permissible.
Warning: Horizontally venting to a sidewall vent terminator (without power vent) is not permissible
Apower vent, with a
3.6.2Vertical venting
BA 5 inch diameter gas vent constructed of double wall Type B gas vent is recommended. A 6 inch vent is required in elevations greater than 2000 feet, see Fig. 10. Under no circumstances should the vent pipe be reduced in size.
BAn approved gas vent connector must be attached to the top of the water heater and rise vertically at least 12" before entering into an approved gas vent connector elbow.
BThe minimum vertical gas vent height allowed is 6 feet; horizontal vent connectors and elbows are not to be considered in the total gas vent height.
BAll gas vent sections must be secured to each other with sheet metal screws and be properly supported.
Horizontal runs:
Any gas vent section that is greater than 45 degrees from the vertical is considered horizontal. Horizontal sections must slope upwards at least ¼ inch for every foot of its horizontal length and be properly supported. Keep the horizontal section short and avoid too many elbows. The maximum horizontal run allowed is half of the total vertical vent height; horizontal vent connectors and elbows are not to be considered in the total gas vent height.
Vent termination:
The gas vent constructed of double wall Type B gas vent must terminate above the roof surface with a listed vent cap at a height that's in accordance with Fig. 11 and table 2, provided it is at least 8 feet (2.4 m) from a vertical wall or similar obstruction. All other gas vents that are not able to terminate within the minimum specified height allowed must terminate not less than 2 feet (0.6 m) above the highest point where it's passed through the roof and at least 2 feet (0.6 m) higher than any vertical wall or similar obstruction within 10 feet (3.1 m).
LISTED VENT CAP
MINIMUM 6
FEET (1.8M)
LISTED GAS VENT
ESTABLISH A ONE
FOOT RISE BEFORE
ANY ELBOWS
Fig. 9 Flat roof
5” X 6” ADAPTOR USED ON HIGH ALTITUDE
Fig. 10 Vent Adaptor for High Altitude Installations
6 720 608 034 | 9 |