4
highlight suggestions which
will
result in enhanced installation,
reliability, or operation.
UPFLOW
DOWNFLOW
HORIZONTAL
LEFT
AIRFLOW
AIRFLOW
AIRFLOW
AIRFLOW
HORIZONTAL
RIGHT
A93041
Fig. 1 -- Multipoise Orientations
The model 58MEC, 2-Stage, 4-way Multipoise, Gas-Fired,
Category 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 58MEC 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 (15
°
C) db or intermittent operation down to
55
°
F (13
°
C) db such as when used with a night setback
thermostat. Return-air temperature must not exceed 80
°
F (27
°
C)
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
connected for
UPFLOW
applications. Minor modifications are
required when used in
DOWNFLOW, HORIZONTAL RIGHT,
or
HORIZONTAL LEFT
(supply-air discharge direction)
applications as shown in Fig. 1. See details in Applications
section.
Install this furnace only in a location and position as specified in
LOCATION and INSTALLATION sections of these instructions.
Always provide adequate combustion and ventilation air as
specified in section Combustion Air and Vent Pipe Systems of
these instructions to furnace.
Combustion products must be discharged outdoors. Connect this
furnace to an approved vent system only, as specified in the
Combustion Air and Vent Piping sections of these instructions.
Never test for gas leaks with an open flame. Use a commercially
available soap solution made specifically for the detection of
leaks to check all connections, as specified in the GAS PIPING
section of these instructions.
Always install furnace to operate within the furnace’s intended
rise range with a duct system which has an external static
pressure within the allowable range, as specified in the SET
TEMPERATURE RISE section of these instructions and furnace
rating plate.
When a furnace is installed so that supply ducts carry air
circulated by the furnace to areas outside the space containing the
furnace, the return air shall also be handled by duct(s) sealed to
the furnace casing and terminating outside the space containing
the furnace.
A gas-fired furnace for installation in a residential garage must be
installed as specified in the Hazardous Locations section of these
instructions.
The furnace may be used for construction heat provided that the
furnace installation and operation complies with:
S
The furnace is permanently installed with all electrical wiring,
piping, air filters, venting and ducting installed according to
these installation instructions. A return air duct is provided,
sealed to the furnace casing, and terminated outside the space
containing the furnace. This prevents a negative pressure
condition as created by the circulating air blower, causing a
flame rollout and/or drawing combustion products into the
structure.
S
The furnace is controlled by a thermostat. It may not be “hot
wired” to provide heat continuously to the structure without
thermostatic control.
S
Clean outside air is provided for combustion. This is to
minimize the corrosive effects of adhesives, sealers and other
construction materials. It also prevents the entrainment of
drywall dust into combustion air, which can cause fouling and
plugging of furnace components.
S
The temperature of the return air to the furnace is maintained
between 55
°
F (13
°
C) and 80
°
F (27
°
C), with no evening
setback or shutdown. The use of the furnace while the structure
is under construction is deemed to be intermittent operation per
our installation instructions.
S
The air temperature rise is within the rated rise range on the
furnace rating plate, and the firing rate has been set to the
nameplate value.
S
The filters used to clean the circulating air during the
construction process must be either changed or thoroughly
cleaned prior to occupancy.
S
The furnace, ductwork and filters are cleaned as necessary to
remove drywall dust and construction debris from all HVAC
system components after construction is completed.
This furnace is shipped with the following materials to assist in
proper furnace installation. These materials are shipped in the
main blower compartment.
The furnace shall be installed so that the electrical components
are protected from water.
For accessory installation detail, refer to the accessory installation
instruction.
58MEC
