507581-04Page 22  of  60 Issue 2128
Figure 25.  
TYPICAL EXHAUST PIPE CONNECTIONS IN UPFLOW DIRECT OR
NON-DIRECT VENT APPLICATIONS
* When transitioning up in pipe size, use the shortest length of 2” PVC pipe possible.
NOTE: Exhaust pipe and intake pipe must be the same diameter.
2”
2”
2”
2”
or
or
TRANSITION
3”
*2”
2”
EXHAUST
Pipe size determined in Table 5
DO NOT transition 
from smaller to larger 
pipe in horizontal runs 
of exhaust pipe.
030/045/070 Only
TRANSITION
1-1/2”
2”
6”
MINIMUM
Figure 26.  
TYPICAL EXHAUST PIPE CONNECTIONS IN HORIZONTAL DIRECT OR NON-DIRECT VENT
APPLICATIONS (RIGHT-HAND DISCHARGE SHOWN)
SIDE VIEW
45°
MAX
45°
MAX
2”
2”
2”
2”
or
2”
12” max.
EXHAUST
TRANSITION
3”
*2”
*2”
EXHAUST
TRANSITION
1-1/2”
2”
2”
EXHAUST
or
NOTE: 1-1/2” Vent 
Pipe Diameter 
Allowed Only on 
030/045/070 Units
.
DO NOT transition 
from larger to smaller 
pipe in horizontal runs 
of exhaust pipe.
EXHAUST
DO NOT transition 
from smaller to larger 
pipe in horizontal runs 
of exhaust pipe.
* When transitioning up in pipe size, use the shortest length of 2” PVC pipe possible.
NOTE: Exhaust pipe and intake pipe must be the same diameter.