AIR INLET COLLAR
Remove screen and mounting plate from air inlet on rear panel of unit by removing 4 screws. Secure inlet collar and gasket to inlet opening re-using the 4 screws removed in step one.
EXHAUST AIR COLLAR
Secure 5-4” reducer to flue collar on rear panel of unit sizes 090, 105 and 120. Seal per exhaust venting instructions.
VERTICAL TERMINATION
Select location on roof for vent terminal, ensuring adequate space inside the building/structure for concentric vent box. Terminal must be at least 6 feet (1.8m) from any wall or adjoining building. See Figure 22.
Cut a hole through the roof for combustion air pipe. Concentric vent box is to be suspended from the underside of the roof using suitable brackets (field supplied). Before mounting box, cut a length of 6 inch (152mm) (sizes 030-075) or 8 inch (203mm) (sizes 090-120) pipe so that dimension A, Figure 22, is equal to the dimension from the top of the box to the roof surface plus 20 inches or plus maximum expected snow depth, whichever is greater. Fasten pipe to combustion air inlet connection of concentric vent box and seal joint. Insert pipe through roof and fasten vent box in place. Flash and/or caulk pipe to roof. Install inlet air screen assembly and fasten to pipe with screws.
Insert a 5 foot length of Type B vent pipe through the concentric vent box opening (detail A, Figure 20) with the "UP" arrow pointing up. Position the pipe to extend 12 inches beyond the inlet air screen. Secure the Type B vent pipe in position by drilling three small equally spaced holes through the collar of the concentric vent box and inserting sheet metal screws. Install defl ector disk on Type B vent pipe 2-1/2 inches above inlet air screen and fasten with screws. Seal joint between deflector disk and pipe with silicone sealant. Install vent terminal on top of Type B vent pipe, fasten with screws and seal joint.
Connect flue pipe and combustion air pipe from concentric vent box to unit, following instructions on pages 26 and 27. Joint between Type B vent pipe and single wall vent pipe must be sealed with high temperature silicone sealant. (See Figure 21) Collars on unit and on concentric vent box are sized so that crimped ends of combustion air pipes go toward the unit and crimped ends of flue pipes go away from the unit.
HORIZONTAL TERMINATION
Select a location on outside wall for vent terminal. In most applications, the terminal should be on level with the fl ue outlet of the unit less a 1/4 inch per foot pitch for condensate drainage toward the outside of the building. See Figure 23.
The location of the vent terminal must be in accordance with the National Fuel Gas Code ANSI Z223.1 in the U.S. or the Natural Gas Installation Code CAN/CGA-B149.1 or the Propane Gas Installation Code CAN/CGA-149.2 in Canada. See Table 4 for minimum clearances. In Canada, a vent shall not terminate above a meter/ regulator assembly within 3 feet (.9m) horizontally of the vertical centerline of the regulator nor within 6 feet (1.8m) of any gas service regulator vent outlet.
Cut a hole through the wall for a 6 inch (152mm) sizes (030-075) or 8 inch (203mm) sizes (090-120) combustion air pipe. Install thimble if required by local codes or type of wall construction. Concentric vent box may be fastened directly to wall or spaced away from wall using suitable brackets (field supplied). Cut a length of pipe so that it will protrude 4 inches (102mm) through the wall when the box is mounted in position. Fasten pipe to box with sheet metal screws, using at least three screws per joint. Seal joint with silicone sealant. Insert pipe through wall and fasten adapter box in place so that the pipe pitches downward 1/4 inch per foot (21mm/m) toward the outside. Flash and/or caulk pipe on outside wall. Install inlet air screen assembly and fasten to pipe with screws. Insert a 3 foot length of 4 inch (sizes 030-075) or 5 inch (sizes 090-120) Type B vent pipe through the concentric vent box opening (detail A, Figure 20) with the "UP" arrow pointing toward the outside. Position the pipe to extend 12 inches beyond the inlet air screen. Secure the Type B vent pipe in position by drilling three small equally spaced holes through the collar of the concentric vent box and inserting sheet metal screws. Install defl ector disk on Type B vent pipe 2-1/2 inches (63.5mm) from inlet air screen and fasten with screws. Install vent terminal on end of Type B vent pipe, fasten with screws and seal joint.
Connect flue pipe and combustion air pipe from concentric vent box to unit, following instructions on pages 26 and 27. Joint between Type B vent pipe and single wall vent pipe must be sealed with high temperature silicone sealant. (See Figure 21) Collars on unit and on concentric vent box are sized so that crimped ends of combustion air pipes go toward the unit and crimped ends of flue pipes go away from the unit.
