SAFETY CONSIDERATIONS
FURNACE RELIABILITY HAZARD
Improper installation or misapplication of furnace may re-
quire excessive servicing or cause premature component
failure.
Application of this furnace should be indoors with special
attention given to vent sizing and material, gas input rate, air
temperature rise, unit leveling, and unit sizing.
FIRE, EXPLOSION, ELECTRICAL SHOCK AND
CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in electrical shock,
fire, personal injury, or death.
Improper installation, adjustment, alteration, service, mainte-
nance, or use can cause carbon monoxide poisoning, explo-
sion, fire, electrical shock, or other conditions which may
cause personal injury or property damage. Consult a qualified
installer, service agency, local gas supplier, or your distribu-
tor or branch for information or assistance. The qualified
installer or agency must use only factory-authorized and
listed kits or accessories when modifying this product.
Installing and servicing heating equipment can be hazardous due to
gas and electrical components. Only trained and qualified
personnel should install, repair, or service heating equipment.
Untrained personnel can perform basic maintenance functions
such as cleaning and replacing air filters. All other operations must
be performed by trained service personnel. When working on
heating equipment, observe precautions in literature, on tags, and
on labels attached to or shipped with unit and other safety
precautions that may apply.
These instructions cover the minimum requirements and conform
to existing national standards and safety codes. In some instances,
these instructions exceed certain local codes and ordinances,
especially those that may not have kept up with changing residen-
tial construction practices. We require these instructions as a
minimum for a safe installation.
Wear safety glasses and work gloves.
CUT HAZARD
Failure to follow this caution may result in personal injury.
Sheet metal parts may have sharp edges or burrs. Use care and
wear appropriate protective clothing and gloves when han-
dling parts.
Have a fire extinguisher available during start-up and adjustment
procedures and service calls.
Recognize safety information. This is the safety-alert symbol
.
When you see this symbol on the unit and in instructions or
manuals, be alert to the potential for personal injury.
Understand these signal words: DANGER, WARNING, and
CAUTION. These words are used with the safety-alert symbol.
DANGER identifies the most serious hazards which will result in
severe personal injury or death. WARNING signifies hazards
which could result in personal injury or death. CAUTION is used
to identify unsafe practices which may result in minor personal
injury or product and property damage. NOTE is used to highlight
suggestions which will result in enhanced installation, reliability,
or operation.
The model 58MTB, 2-Stage, 4-way multipoise, Gas-Fired, Cat-
egory IV, condensing furnace is available in model sizes ranging
in high-stage gas input rates of 60,000 to 120,000 Btuh. This
furnace is CSA (formerly AGA and CGA) design-certified for
natural and propane gases (see furnace rating plate) and for
installation in alcoves, attics, basements, closets, utility rooms,
crawlspaces, and garages. This furnace is factory-shipped for use
with natural gas. A CSA listed gas conversion kit is required to
convert furnace for use with propane gas.
See Fig. 3 for required clearances to combustibles.
This furnace SHALL NOT be installed directly on carpeting, tile,
or any other combustible material other than wood flooring. For
downflow installations, a factory accessory floor base must be
used when installed on combustible materials and wood flooring.
Special base is not required when this furnace is installed on the
manufacturer’s coil assembly or when the manufacturer’s coil box
is used. The design of the 58MTB furnace is not CSA certified for
installation in mobile homes, recreational vehicles, or outdoors.
This furnace is suitable for installation in a structure built on site
or a manufactured building completed at final site.
This furnace is designed for continuous return-air minimum
temperature of 60°F db or intermittent operation down to 55°F db
such as when used with a night setback thermostat. Return-air
temperature must not exceed 80°F db. Failure to follow these
return air limits may affect reliability of heat exchangers, motors
and controls. (See Fig. 4.)
This furnace is shipped with the drain and pressure tubes con-
nected for UPFLOW applications. Minor modifications are re-
quired when used in DOWNFLOW, HORIZONTAL RIGHT,
or HORIZONTAL LEFT (supply-air discharge direction) appli-
cations as shown in Fig. 1. See details in Applications section.
Fig. 1—Multipoise Orientations
A93041
UPFLOW
DOWNFLOW
HORIZONTAL
LEFT
AIRFLOW
AIRFLOW
AIRFLOW
AIRFLOW
HORIZONTAL
RIGHT
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