SECTION 6: VENTING
SECTION 6: VENTING 6.1 Venting
This heater must be vented in accordance with the rules contained in this manual and with the following national codes and any state, provincial or local codes which may apply: United States: Refer to NFPA 54/ANSI Z223.1 - latest revision, National Fuel Gas Code; Canada: Refer to CSA B149.1 Natural Gas and Propane Installation Code.
Any portion of vent pipe passing through a combustible wall must have a listed thimble to conform with the above codes.
The heater may be installed unvented in certain circumstances according to building ventilation codes. Refer to the above codes and Page 8, Section 6.3 for further information. Unvented operation also requires compliance with the clearances to combustibles given on Page 4, Figure 1.
The bottom of the vent or air intake terminal shall not be located less than 1' (.3 m) above grade level.
The vent shall not terminate less than 7' (2.1 m) above grade where located adjacent to public walkways.
Vent terminal must be installed at a height sufficient to prevent blockage by snow and building materials protected from degradation by flue gasses.
Vent terminal must be beyond any combustible overhang.
Secure all joints with corrosion resistant #8 x 3/8" sheet metal screws.
For single wall venting, pressure sensitive aluminum tape or silicone sealant must be used to seal all joints.
Aluminum tape shall have a minimum temperature rating of 400° F (204° C) and meet SMACNA AFTS-
6.1.1 United States Requirements
Vent must terminate at least 3' (.9 m) above any forced air inlet located within 10' (3.1 m).
Vent must terminate at least 4' (1.2 m) below,
4' (1.2 m) horizontally from, or 1' (.3 m) above any door, operable window, or gravity air inlet into any building.
NFPA 54/ANSI Z223.1 - latest revision, National Fuel Gas Code specifies a 4' (1.2 m) horizontal vent terminal clearance from gas and electric meters, regulators and relief equipment.
6.1.2 Canadian Requirements
The vent shall not terminate within 6' (1.8 m) of a mechanical air supply inlet to any building.
The vent shall not terminate within 3' (.9 m) of a window or door that can be opened in any building, any
6.2 Vent Installation
WARNING
Fire Hazard
Some objects will catch fire or explode when placed close to heater.
Keep all flammable objects, liquids and vapors the required clearances to combustibles away from heater.
Failure to follow these instructions can result in death, injury or property damage.
For vented units, the vent must terminate outside of the building.
Vents must be fully sealed and correctly sized for the model. If the vent passes through a wall or ceiling of combustible material, it must be enclosed by a listed thimble and be separated from the thimble by at least a 2" (5 cm) air gap.
For separated combustion models, vents and air intakes must be a fully sealed system and correctly sized for the model. Vent should be assembled as detailed on Page 9, Figure 3 through Page 12, Figure 8. The joints between the vent terminal and the roof or wall must be properly sealed. If the vent passes through a wall or ceiling of combustible material, it must be enclosed by a listed thimble and be separated from the thimble by at least a 2" (5 cm) air gap.
Vents and air intakes must be adequately supported so that the heater does not bear the weight of the pipes.
For vent termination See Page 9, Figure 3 through Page 12, Figure 8.
6.2.1Standard Vented Heaters (Models UHA 150 - 400)
The vent must be fitted with a low resistance terminal. See Page 9, Figure 3 through Page 9, Figure 4. Standard vented heaters do not allow outdoor air intake for combustion air.
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