HORIZONTALLY VENTED UNIT HEATERS
(CATEGORY III)
Horizontal venting arrangements are designed to be used with single wall vent pipe. Horizontal venting arrangements must terminate external to the building using either single wall or double wall (Type B) vent. If single wall vent pipe is used, it must be constructed of 26 gauge galvanized steel or a material of equivalent durability and corrosion resistance for the vent system. For installations in Canada, use corrosion resistant and
Do not use Type B (double wall) vent internally within the building on horizontally vented power vented units!
If double wall venting is used, components which are UL Listed and approved for Category III positive pressure venting systems MUST be used.
A Breidert Type L, Fields Starkap, or equivalent vent cap must be supplied by the customer for each power vented unit. The vent pipe diameter MUST be as specified in Table 1 (“D” Dia. Flue Opening). All unit sizes are factory equipped with the required flue size collar; attach in place (if not mounted to outlet); refer to included vent collar instruction sheet for additional requirements.
Vent Systems - Termination Clearance Requirements
| Minimum Clearances for |
Structure | Termination Locations |
|
|
| 4 feet below |
Door, window or any gravity air inlet | 4 feet horizontally |
| 1 foot above |
|
|
Forced air inlet within 10 ft. | 3 feet above |
|
|
Adjoining building or parapet | 6 feet |
|
|
Adjacent public walkways | 7 feet above grade |
|
|
The venting system for these appliances shall terminate at least 4 feet (1.2m) below, 4 feet (1.2m) horizontal from, or 1 foot (0.3m) above any door, window, or gravity vent air inlet into the building.
The vent terminal must be at least 12 inches (305mm) from the exterior of the wall that it passes through to prevent degradation of the building material by flue gases.
The vent terminal must be at least 3 feet (1m) above grade, or in snow areas, at least 3 feet above the snow line to prevent blockage by snow.
Through the wall vent for these appliances shall NOT terminate over public walkways, or over an area where the condensate or vapor could create a nuisance or hazard or could be detrimental to the operation of regulators, relief valves, or other equipment.
The vent pipe equivalent length must not exceed 50 feet (15.2m). Equivalent length is the total length of straight sections PLUS 15 feet (4.6m) for each 90 elbow and 8 feet (2.44m) for each 45 elbow.
Maintain 6 inches (152mm) between the vent pipe and combustible materials.
The vent terminal must be installed with a minimum horizontal clearance of 4 feet (1.2m) from electric meters, gas meters, regulators, and relief equipment.
Seal all vent pipe joints and seams to prevent leakage. Use General Electric
Horizontal portions of the venting systems shall be supported at maximum intervals of 4 feet (1.2m) to prevent sagging (in Canada, support at 3 feet (1m) maximum intervals).
Insulate single wall vent pipe exposed to cold air or running through unheated areas.
Each unit must have an individual vent pipe and vent terminal! Each unit MUST NOT be connected to other vent systems or to a chimney.
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