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Furnace with Evaporator Coil Using a Separate Drain
(Unit shown in horizontal left-hand discharge position)
.
5’ max.
PVC Pipe Only
4”min
5”max
Evaporator
Coil
Drain Pan
Condensate
DrainConnection
Field Provided Vent
(4” min. to 5” max. above
condensate connection)
Piping from furnace and evaporator coil must slope down a minimum 1/4” per ft. toward trap
(Trap at coil is optional)
FIGURE 51
Furnace with Evaporator
Coil Using a Common Drain
(1” min. to 2” Max.above
condensatedrain connection)
Condensate
DrainConnection
Evaporator drain
line required
(Trap at coil is optional)
FIGURE 52
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.
Furnace with Evaporator Coil Using a Common Drain
(Unit shown in horizontal left−hand discharge position)
Condensate Drain
Connection
(4” min. to 5” Max.above
condensatedrain connection)
5’ max.
PVC Pipe Only
4”min
5”max
Evaporator
Coil
Drain Pan
Piping from furnace and evaporator coil must slope
down a minimum 1/4” per ft. toward trap
(Trap at coil is optional)
FIGURE 53