Goodman GRL SERIES Installation Instructions Manual page 24

FIGURE 18
TWO FURNACE VENTING THROUGH ROOF
TWO-PIPE VENTING
COMBUSTION
AIR INTAKE
2" PVC
CONCENTRIC VENTING
8" MIN.
24" MAX.
MINIMUM 12" ABOVE AVERAGE
SNOW ACCUMULATION. MAXIMUM
OF 24 IN. ABOVE ROOF.
MULTIVENTING
IF VENTING TWO OR MORE
FURNACES NEAR EACH OTHER IS
REQUIRED, EACH FURNACE
MUST BE INDIVIDUALLY VENTED
– NO COMMON VENTING IS
PERMITTED. See Figures 18 and 19
for positioning of the terminations.
When more than two furnaces are to
be vented, there must be at least 4
feet between the first two furnaces
and the third, etc.
24
3" MIN.
24" MAX.
SEE CONCENTRIC
VENT INSTALLATION
INSTRUCTIONS
FIGURE 19
TWO FURNACE VENTING THROUGH WALL
TWO-PIPE VENTING
3" MIN.
24" MAX.
CONCENTRIC VENTING
6' MINIMUM
6" MINIMUM
10" RECOMMENDED
10' RECOMMENDED
MINIMUM 12"
MINIMUM 12"
ABOVE GRADE ABOVE GRADE
MAXIMUM 1"
MAXIMUM 1"
DISTANCE
DISTANCE
FROM WALL FROM WALL
8"
SEE CONCENTRIC VENT INSTALLATION
8" MIN.
INSTRUCTIONS.
24" MAX.
COMBUSTION
AIR INTAKE
2" PVC COUPLING
WITH VALVE IN
VERTICAL POSITION
EXHAUST VENT