Bryant 581A - Manual (Page 2)

INDUCED-DRAFT COMBUSTION provides the exact amount
of combustion air for the most efficient operation. Induced-draft
combustion also eliminates the flue stack, giving the unit a low
profile appearance. The draw-through design ensures safe op-
eration under any conditions.
INTERMITTENT SPARK IGNITION eliminates the standing pi-
lot flame that consumes gas when the furnace is shut down. The
pilot is ignited only when the thermostat calls for heat.
TUBULAR U-SHAPED CELL design of the heat exchanger
provides high-efficiency heating operation. The hot gases make
2 passes over the supply-air path to enhance efficiency.
POSITIVE-PRESSURE MECHANICAL FLUE GAS VENTING
is unaffected by adverse wind conditions.
FURNACE SAFETY CONTROLS shut off gas if there is a pilot
outage, combustion-air failure, overheating of heat exchangers,
or flame rollout.
TWO-STAGE HEATING WITH 2 INDEPENDENT GAS CON-
TROL SYSTEMS (180,240 units) minimizes heating costs.
These independent gas control systems make single-stage
heating possible if one stage fails.
ADVANCED DESIGN of evaporator and condenser coils pro-
vides optimum heat transfer and cooling efficiency. Coils are
computer-designed with advanced heat transfer surfaces, and
are fabricated of copper tubing with aluminum fins.
COMMERCIAL STRENGTH BASE RAILS with built-in rigging
capability allow easy rigging of unit.
WEATHER-RESISTANT CABINET is built for durability in any
climate. The cabinet is made of pre-painted, galvanized steel for
long life and high-quality appearance.
LOW-AMBIENT OPERATION is provided standard. The units
operate in cooling down to 35 F as shipped from the factory.
Low-ambient kits are not required for most applications.
COMPRESSOR VIBRATION ISOLATION MOUNTING on all
units eliminates noise-causing vibration transmission into the
conditioned space.
CRANKCASE HEATERS keep the oil free of refrigerant during
the off cycle for added compressor life and reliability.
STANDARD WARRANTIES include 1 year on parts (no labor),
with an additional 4 years on compressors (155 units) and
heat exchangers (all units). Additional extended warranties are
available.
BELT-DRIVEN EVAPORATOR-FAN MOTORS are standard on
all units and allow adjustment of the available static pressure to
meet the job requirements of even the most demanding
applications.
FACTORY-INSTALLED OPTIONS DESCRIPTION
AND USAGE
Economizer — The economizer will allow a fixed percentage
(between 0 and 100%) outdoor ventilation air into the unit any
time the evaporator fan is running. A dry-bulb thermostat placed
outdoors will bring in 100% outdoor air whenever the tempera-
ture of the outdoor air alone will adequately provide cooling. If
the economizer alone cannot provide enough cooling, then si-
multaneous economizer and compressor operation will provide
the most economical operation.
SUGGESTED USE:
• To allow a fixed percentage of outdoor air any time the evapo-
rator fan is on, or operates in economizer mode if outdoor air
can provide cooling, but closes when the evaporator fan is off
to prevent cold backdrafts and wasted energy.
• To reduce energy usage. Use whenever the number of hours
of operation at below 55 F is significant.
• The damper may be used on either vertical or horizontal
applications.
Manual Outdoor-Air Dampers — Package consists of a
damper which can be set at 25% outdoor air. The package in-
cludes a rainhood and birdscreen.
SUGGESTED USE
• To allow a fixed percentage of outdoor air for ventilation under
all conditions.
• The damper may be used on either vertical or horizontal
applications.
NOTE: The 25% manual outdoor-air damper will be factory
installed whenever the factory-installed economizer is not
chosen.
FIELD-INSTALLED ACCESSORY
DESCRIPTION AND USAGE
Roof Curbs (Horizontal and Vertical) — Full-perimeter galva-
nized steel support frame in 14- and 24-in. high designs pro-
vides wood nailer to attach roof counter flashing. Insulated
basepans in curb are provided to prevent condensation. Duct-
work attaches to rails provided in the roof curb. A gasket is pro-
vided to form an air- and watertight seal between unit and curb.
The gasket meets the standards of the NRCA (National Roofing
Contractors’ Association).
SUGGESTED USE:
• Rooftop application for vertical or horizontal discharge.
• Slab-mounted applications when elevation of the unit is
necessary.
Horizontal Adapter — The adapter is prefabricated, factory-
assembled with built-in insulated duct, and permits full perim-
eter mounting.
SUGGESTED USE:
• Rooftop applications for horizontal discharge where high air
delivery cfms are required.
Two-Position Damper — Package consists of a low-leak
damper assembly for easy installation. The damper will allow ei-
ther 0 or 25% outdoor air into the unit any time the evaporator
fan is running. When the evaporator fan is off or when there is a
loss of power, the damper will be closed.
SUGGESTED USE:
• Allows a fixed percentage of outdoor air any time the evapo-
rator fan is on, but closes when the evaporator fan is off to
prevent cold backdrafts and wasted energy.
• The damper may be used on either vertical or horizontal air-
flow applications.
Economizer — See description listed under Factory-Installed
Options Description and Usage section above.
CONTENTS
Page
Model Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Heating Capacities and Efficiencies . . . . . . . . . . . . . . . . . . . 4
Capacity Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Dimensional Drawings . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-8
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9,10
Selection Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Gross Cooling Capacities . . . . . . . . . . . . . . . . . . . . . . . . 12-14
Air Delivery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-17
Electrical Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Operating Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Typical Wiring Schematic . . . . . . . . . . . . . . . . . . . . . . . . . 20,21
Typical Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Application Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23,24
Engineers’ Specification Guide . . . . . . . . . . . . . . . . . . . . . . 25
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