Reznor SCE Unit Installation Manual - Manual (Page 13)

Form RZ-NA I-SCE, Mfg #207697 Rev 7, Page 13
HORIZONTAL VENT
INSTRUCTIONS
(cont’d)
3. Prepare a hole through the outside wall for the 8" (203mm) diameter combustion air
pipe. Outside wall construction thickness should be between 1" (25mm) minimum and 48"
(1143mm) maximum. The larger diameter combustion air pipe serves as clearance for the
vent pipe on non-combustible construction. A thimble may be required depending on wall
construction and/or local codes.
4. Prepare the Concentric Adapter Box
a) Attach the brackets to the box. Follow the instructions in FIGURE 12 .
b) Attach the outside portion of the combustion air pipe to the box. Determine the length
by measuring the bracket length from box to wall, plus the wall thickness, plus 2" (51 mm).
(The inlet air pipe should extend beyond the outside wall approximately 2" (51mm).)
Attach the inlet air pipe to the collar of the concentric adapter with sheetmetal screws and
seal.
5. Attach the concentric adapter box to the wall. Insert the combustion air pipe through
the wall. Attach the brackets ( FIGURE 12 ) to the wall. On the outside, caulk or flash the
inlet air pipe. Flashing is field-supplied.
6. Position the inlet guard over the end of the combustion air pipe. See FIGURE 13 , page
14. Attach the guard to the inlet air pipe with the four 1/2" long screws provided.
7. Determine length and install the double-wall terminal vent pipe.
a) Determine length of pipe. The length of the vent pipe is determined by the installation
within the maximum and minimum requirements. The vent pipe extending through the box
and the inlet air pipe must be one piece of double-wall vent pipe without joints. See FIGURE
13, to determine lengths of each segment and calculate the total length required. The transi-
tion to the single-wall or Category III vent pipe run, must be made a maximum of 6” (152mm)
from the heater side of the box.
b) Install double-wall terminal vent pipe. Being sure the vent pipe is in the proper flow
direction, slide the end through the box. Position the vent pipe so that it will extend between
16" (406mm) and 24” (610mm) past the end of the combustion air pipe and no more than 6”
(152mm) out of the box toward the heater.
Use a taper-type reducer to attach the 5" double-wall vent pipe to the 6" or 7" single-wall or
Category III vent pipe run. Follow the instructions in FIGURE 9 , page 9.
8. Attach the exhaust (vent) cap to the end of the vent pipe. Align the cap so that its baffle
strips are positioned on the horizontal and vertical centerlines (See FIGURE 13). Follow
the instructions in FIGURE 8 , page 9, to attach the exhaust cap. (NOTE: If vent pipe is
inserted from outside, cap may be attached before the double-wall vent pipe is installed. If
cap is attached first, be sure the baffle strips are positioned correctly when attaching the
vent terminal pipe to the vent run.)
9. Seal the vent pipe. Verify that the double-wall section of vent pipe has a slight downward
drop (1/4” per foot/6mm per 305mm) toward the vent terminal end. Use silicone sealant and
seal the circumference of the pipe and the opening of the box. Seal the area around the pipe
FIGURE 12 - Brackets for
Attaching the Concentric
Adapter Box to the Wall