Lennox G51MP SERIES Installation Instructions Manual page 22

TYPICAL AIR INTAKE PIPE CONNECTIONS
UPFLOW OR DOWNFLOW DIRECT VENT APPLICATIONS
(Right−Hand Exit in Upflow Application Shown)
PLUG
(Must be
glued in
place)
TYPICAL AIR INTAKE PIPE CONNECTIONS
HORIZONTAL DIRECT VENT APPLICATIONS
(Horizontal Right−Hand Air Discharge Application Shown)
*Limit pipe
length to 4" in
−135 applications.
−24B−045
−36B−045
−36B−070
−36C−090
−48C−090
−60C−090
48C−110
−60C−110
−24B−045
−36B−045
−36B−070
−36C−090
−48C−090
48C−110
−60C−090
60C−110
FIGURE 26
2
2
2
−24B−045
−36B−045
−36B−070
−36C−090
−48C−090
−48C−110
−60C−090
−60C−110
FIGURE 25
−24B−045
−36B−045
−36B−070
−36C−090
2−1/2",
−48C−090
3" OR 4"
−60C−090
48C−110
−60C−110
−60D−135*
TRANSITION
*2"
2−1/2",
3" OR 4"
2"
2"
TRANSITION
2"
2"
2"
2"
2−1/2",
3" OR
4
TRANSITION
2
2
2
−24B−045
−36B−045
−36B−070
−36C−090
−48C−090
−60C−090
−48C−110
−60C−110
*Limit pipe length to 4"
in −135 applications.
Follow the next three steps when installing the unit in Non-
Direct Vent applications where combustion air is taken
from indoors and flue gases are discharged outdoors.
TYPICAL AIR INTAKE PIPE CONNECTIONS
UPFLOW OR HORIZONTAL NON−DIRECT
VENT APPLICATIONS
(Right−Hand Exit in Upflow Application Shown)
PLUG
(Must be
glued in
place)
NOTE − Debris screen and elbow may be rotated, so that
screen may be positioned to face forward, backward or
downward.
Page 22
2−1/2",
3" OR
4
TRANSITION
*2"
−24B−045
−36B−045
−36B−070
−36C−090
−48C−090
−60C−090
−48C−110
60C−110
−60D−135*
6 in. Max.
INTAKE
DEBRIS
SCREEN
(Provided)
FIGURE 27