Lennox EL296DFE Series Manual page 42

Furnace with Evaporator Coil
Using a Separate Drain
Field Provided Vent
1" min. 2" max. above
condensate drain.
Condensate
Drain Connection
Evaporator Drain Line
(vent required)
FIGURE 48
IMPORTANT
When combining the furnace and evaporator coil
drains together, the A/C condensate drain outlet
must be vented to relieve pressure in order for the
furnace pressure switch to operate properly.
Field Provided Vent
1" min. 2" max. above
condensate drain.
Condensate
Drain Connection
Evaporator Drain Line
(vent required)
Drain
Page 42
Furnace with Evaporator
Coil Using a Common Drain
FIGURE 49