Table of Contents
Advertisement
Indoor Coil Placement
In cooling / heat pump applications, Lennox recommends that
the indoor coil be installed at least 4 inches above the top of the
furnace cabinet to allow proper airflow. If coil cabinet does not
provide proper clearance, use field−fabricated transition.
Venting
WARNING
Combustion air openings in front of the furnace must
be kept free of obstructions. Any obstruction will
cause improper burner operation and may result in
a fire hazard.
WARNING
The barometric draft control shall be in the same at-
mospheric pressure zone as the combustion air inlet
to the furnace. Deviation from this practice will cause
improper burner operation and may result in a fire
hazard.
CAUTION
Do not store combustible materials near the furnace
or supply air ducts. The material (such as paint, mo-
tor oil, gasoline, paint thinner, etc.) may ignite by
spontaneous combustion creating a fire hazard.
WARNING
This furnace is certified for use with type L" vent.
B" vent must not be used with oil furnaces.
Prior to installation of unit, make a thorough inspection of the
chimney to determine whether repairs are necessary. Make
sure the chimney is properly constructed and sized accord-
ing to the requirements of the National Fire Protection Asso-
ciation. The smallest dimensions of the chimney should be
at least equal to the diameter of the furnace vent connector.
Make sure the chimney will produce a steady draft sufficient
to remove all the products of combustion from the furnace. A
draft of at least .04" w.c. (9.9 Pa) is required during burner
operation.
1 − Local building codes may have more stringent installa-
tion requirements and should be consulted before
installation of unit.
2 − The vent connector should be as short as possible to
do the job.
3 − The vent connector should not be smaller than the out-
let diameter of the vent outlet of the furnace.
4 − Pipe should be at least 24 gauge galvanized.
5 − Single wall vent pipe should not run outside or through
any unconditioned space.
6 − Chimney should extend 3 feet (0.9 m) above highest
point where the vent passes through the roof, and 2
feet (0.6 m) higher than any portion of a building within
a horizontal distance of 10 feet (3 m).
7 − The vent must not pass through a floor or ceiling.
Clearances to single wall vent pipe should be no less
than 6" (152 mm); more if local codes require it.
8 − The vent may pass through a wall where provisions
have been made for a thimble as specified in the Stan-
dards of the National Board of Fire Underwriters. See fig-
ure 8.
Combustible
Wall
9 − The vent pipe should slope upward toward the chim-
ney on horizontal run at least 1/4 inch (6 mm) to the
foot (0.3 m) and should be supported by something
other than the furnace, such as isolation hangers.
10 − Extend the vent pipe into the chimney so that it is flush
with the inside of the chimney liner. Seal the joint be-
tween the pipe and the liner.
11 − The furnace shall be connected to either a factory−built
chimney or vent which complies with a recognized
standard, or to a masonry or concrete chimney which
has been lined with a material acceptable to the au-
thority having jurisdiction.
12 − When two or more appliances vent into a common
vent, the area of the common vent should not be less
than the area of the largest vent or vent connection
plus 50% of the area of the additional vent or vent con-
nection. Chimney must be able to sufficiently vent all
appliances operating at the same time.
Page 8
Wall Thimble
Thimble
Vent Pipe
Figure 8
Advertisement
Table of Contents
