Details of Intake and Exhaust Piping Terminations for Direct Vent Installations
NOTE - In Direct Vent installations, combustion air is tak en from outdoors and flue gases are discharged to out
Inches(MM)
3”(76MM) MAX.
SIZE TERMINATION PIPE PER TABLE 8.
UNCONDITIONED
doors.
NOTE - Flue gas may be slightly acidic and may adversely affect some building materials. If any vent termination is used and the flue gasses may impinge on the building ma terial, a
8” (203MM) MIN
12” (305MM) ABOVE |
AVERAGE SNOW |
ACCUMULATION |
ATTIC SPACE
1/2” (13MM) FOAM
INSULATION IN
UNCONDITIONED
SPACE
optional tee is used, the protective shield is recommended. The shield should be constructed using wood, plastic, sheet metal or other suitable material. All seams, joints, cracks, etc. in the affected area should be sealed using an appropriate sealant. See figure 35.
Intake and exhaust pipes may be routed either horizontally through an outside wall or vertically through the roof. In at tic or closet installations, vertical termination through the roof is preferred. Figures 32 through 46 show typical terminations.
1 - Intake and exhaust terminations are not required to be in the same pressure zone. You may exit the intake on one side of the structure and the exhaust on another side (figure 33). You may exit the exhaust out the roof and the intake out the side of the structure (figure 34).
2 - Intake and exhaust pipes should be placed as close together as possible at termination end (refer to il lustrations). Maximum separation is 3” (76MM) on roof terminations and 6” (152MM) on side wall termina tions.
NOTE - When venting in different pressure zones, the maximum separation requirement of intake and ex haust pipe DOES NOT apply.
3 - On roof terminations, the intake piping should termi nate straight down using two 90° elbows (See figure 32).
3” (76MM) OR 2” (51MM) PVC
PROVIDE SUPPORT
FOR INTAKE AND
EXHAUST LINES
DIRECT VENT ROOF TERMINATION KIT
(15F75 or 44J41)
FIGURE 32
Exiting Exhaust and Intake Vent
(different pressure zones)
Exhaust | Furnace | Inlet Air | |
(Minimum 12 in. | |||
Pipe | |||
| 305 MM) above | ||
|
| ||
|
| grade or snow | |
|
| accumulation |
FIGURE 33
Exiting Exhaust and Intake Vent
(different pressure zones)
4 - Exhaust piping must terminate straight out or up as shown. A reducer may be required on the exhaust pip ing at the point where it exits the structure to improve the velocity of exhaust away from the intake piping. See table 8.
NOTE - Care must be taken to avoid recirculation of ex haust back into intake pipe.
5 - On
Roof Terminated
Exhaust Pipe
Furnace
Inlet Air (Minimum 12 in. 305 MM) above grade or snow
accumulation
should be as short as possible. See figures 36 and 37.
6 - On
FIGURE 34
TABLE 8
EXHAUST PIPE TERMINATION SIZE REDUCTION
EL296UHE | Termination |
MODEL | Pipe Size |
|
|
*045 and 070 | |
*090 | 2” (51MM) |
110 | 2” (51MM) |
135 | 2” (51MM) |
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