035-17438-001 Rev. A (901)
Unitary Products Group
5
Specially Engineered Installations
The above requirements shall be permitted to be waived
where special engineering, approved by the authority having
jurisdiction, provides an adequate supply of air for combus-
tion, ventilation and dilution of flue gases.
Combustion Air Quality
The recommended source of combustion air is to use the out-
door air supply. Excessive exposure to contaminated com-
bustion air will result in safety and performance related
problems. However, the use of indoor air in most applications
is acceptable, except as follows:
1.
If the furnace is installed in a confined space it is recom-
mended that the necessary combustion air come from
the outdoors by way of attic, crawl space, air duct or
direct opening.
2.
If outdoor combustion air is used, there must be no expo-
sure to the installations or substances listed in number 3
below.
3.
The following types of installations may require OUT-
DOOR AIR for combustion, due to chemical exposure.
a.
Commercial buildings
b.
Buildings with indoor pools
c.
Furnaces installed in laundry rooms
d.
Furnaces installed in hobby or craft rooms
e.
Furnaces installed near chemical storage areas
Exposure to the following substances in the combustion air
supply may also require OUTDOOR AIR for combustion.
f.
Permanent wave solutions
g.
Chlorinated waxes and cleaners
h.
Chlorine based swimming pool chemicals
i.
Water softening chemicals
j.
De-icing salts or chemicals
k.
Carbon tetrachloride
l.
Halogen type refrigerants
m. Cleaning solvents (such as perchloroethylene)
n.
Printing inks, paint removers, varnishes, etc.
o.
Hydrochloric acids
p.
Cements and glues
q.
Antistatic fabric softeners for clothes dryers
r.
Masonry acid washing chemicals
VENTING
CATEGORY I VERTICAL VENTING
Category I venting consists of vertically venting one or more
appliances in B-vent or masonry chimney (as allowed), using
single wall metal pipe or B-vent connectors. Type B-vent sys-
tem extends in a general vertical direction and does not con-
tain offsets exceeding 45 degrees, except that a vent system
having not more than one 60 degree offset is permitted.
NOTE:
This appliance may be common vented with another
gas appliance as allowed by the following codes and stan-
dards.
All installations must be vented in accordance with the
National Fuel Gas Code, NFPA 54/ANSI Z223.1 latest edi-
tion. For reference, the National Fuel Gas Code Handbook,
available from NFPA (item JP54HB96) is recommended. The
appliance must also be vented in compliance with all local
utility and code requirements. In Canada, the furnace must
be vented in accordance with the National Standard of Can-
ada, CAN/CGAB149.1 and .2 latest editions.
VENTING INTO AN EXISTING CHIMNEY
Whenever possible, B-1 metal pipe should be used for vent-
ing. Where use of an existing chimney is unavoidable, the fol-
lowing rules must be followed:
1.
The masonry chimney must be built and installed in
accordance with nationally recognized building codes or
standards and must be lined with approved fire clay tile
flue liners or other approved liner material that will resist
corrosion, softening, or cracking from flue gases. THIS
FURNACE IS NOT TO BE VENTED INTO AN UNLINED
MASONRY CHIMNEY.
2.
This furnace may be vented into a fire clay tile lined
masonry chimney only if a source of dilution air is pro-
vided, such as by common venting with a draft hood
equipped water heater. If no such source of dilution air is
available, Type B vent must be used, or masonry chim-
ney vent kit 1CK0603 or 1CK0604 must be used. See
instruction 035-17452-000 to properly apply these
masonry chimney kits.
3.
The chimney must extend at least three feet above the
highest point where it passes through a roof of a building
and at least two feet higher than any portion of the build-
ing within a horizontal distance of ten feet.
4.
The chimney must extend at least five feet above the
highest equipment draft hood or flue collar.
It is the responsibility of the installer to verify
proper vent system operation.
A furnace shall not be connected to a chimney flue
serving a separate appliance designed to burn
solid fuel.
