Installation instructions, Warning, Exhaust system checklist – GE PFMN445 User Manual
Page 27: Exhaust length
27
Installation Instructions
EXHAUST SYSTEM CHECKLIST
HOOD OR WALL CAP
• Terminate in a manner to prevent back drafts
or entry of birds or other wildlife.
• Termination should present minimal resistance
to the exhaust airflow and should require little
or no maintenance to prevent clogging.
• Never install a screen in or over the exhaust
duct. This could cause lint buildup.
• Wall caps must be installed at least 12″ above
ground level or any other obstruction with the
opening pointed down.
SEPARATION OF TURNS
For best performance, separate all turns
by at least 4 ft. of straight duct, including
the distance between the last turn and
the exhaust hood.
TURNS OTHER THAN 90º
• One turn of 45º or less may be ignored.
• Two 45º turns should be treated as one
90º turn.
• Each turn over 45º should be treated as
one 90º turn.
SEALING OF jOINTS
• All joints should be tight to avoid leaks.
The male end of each section of duct must
point away from the dryer.
• Do not assemble the ductwork with fasteners
that extend into the duct. They will serve as
a collection point for lint.
• Duct joints can be made air- and moisture-tight
by wrapping the overlapped joints with duct
tape.
• Horizontal runs should slope down toward
the outdoors 1/2″ per foot.
INSULATION
Ductwork that runs through an unheated area
or is near air conditioning should be insulated
to reduce condensation and lint buildup.
WARNING –
USE ONLY METAL
4″ DUCT. DO NOT USE DUCT LONGER THAN
SPECIFIED IN THE EXHAUST LENGTH TABLE.
Using exhaust longer than specified length will:
• Increase the drying times and the energy cost.
• Reduce the dryer life.
• Accumulate lint, creating a potential
fire hazard.
The correct exhaust installation is YOUR
RESPONSIBILITY.
Problems due to incorrect installation
are not covered by the warranty.
The MAXIMUM ALLOWABLE length of
the exhaust system depends upon the type
of duct, number of turns, the type of exhaust
hood (wall cap) and all conditions noted below.
EXHAUST LENGTH
RECOMMENDED MAXIMUM LENGTH
Exhaust Hood Types
Recommended
Use only for short-
run installations
No. of 90º
Rigid
Rigid
Elbows
Metal
Metal
0
150 Feet
125 Feet
1
135 Feet
115 Feet
2
125 Feet
105 Feet
3
115 Feet
95 Feet
4
105 Feet
85 Feet
5
95 Feet
75 Feet
4″ DIA
4″
2
1
⁄
2
″
4″ DIA
4″ DIA