Bryant 579F - Manual (Page 63)

ENGINEERS’ SPECIFICATION GUIDE — MODELS 580D036-150 (3 TO 12 1 ⁄
2
TONS)
GENERAL: Furnish and install single-package, outdoor rooftop-
mounted, electrically controlled, heating and cooling unit utiliz-
ing a reciprocating compressor(s) for cooling and gas
combustion for heating duty. Unit shall discharge supply air ver-
tically or horizontally as shown on the contract drawings.
Nominal unit electrical characteristics shall be v,
ph, 60 Hz. The unit shall be capable of satisfactory op-
eration within voltage limits of v to v.
COOLING CAPACITY: Total cooling capacity of the unit shall be
Btuh or greater, and sensible capacity shall be Btuh or
greater at conditions of cfm evaporator air entering at
unit at F dry bulb, F wet bulb and condenser
entering air of F dry bulb. Total design conditions shall
be a minimum of Btuh/Watt. The unit shall be capable
of cooling operation down to 25 F.
HEATING CAPACITY: Total heating capacity of the unit shall be
Btuh or greater with a gas input of Btuh.
CABINET: The cabinet shall be constructed of galvanized steel,
bonderized and coated with a prepainted, baked enamel finish.
COMPRESSOR: Compressor shall be fully-hermetic type with
suitable vibration isolators.
CONDENSER SECTION: The condenser coils shall have alu-
minum plate fins mechanically bonded to seamless copper
tubes with all joints brazed. Condenser fan shall be direct-driven
propeller type and shall discharge air vertically. Fan shall have
permanently lubricated bearings.
EVAPORATOR SECTION: Evaporator coils shall have alumi-
num plate fins mechanically bonded to seamless copper tubes
with all joints brazed. Evaporator fan shall be direct drive with 2
or 3 speeds, or belt drive as shown on the equipment drawings.
Belt drive shall include an adjustable-pitch motor pulley. Motor
bearings shall be sealed, permanently lubricated, ball-bearing
type.
HEATING SECTION: The unit shall be equipped with an
induced-draft combustion system with energy saving direct
spark ignition and redundant main gas valve. The heat ex-
changer shall be of the tubular section type constructed of a
minimum of 20-gage steel coated with a nominal 1.2 mil
aluminum-silicone alloy for corrosion resistance. Burners shall
be of the in-shot type constructed of aluminum coated steel.
REFRIGERANT SYSTEM: Refrigerant system shall include
strainer assembly, fixed orifice feed system, and service gage
connections on suction line, liquid line, and compressor dis-
charge line, as well as internal high-pressure relief.
FILTER SECTION: Filter section shall consist of factory-
installed low velocity, 2-in. thick fiberglass throwaway filters of
commercially available sizes. Filter access panel shall be easy,
tool-less access.
CONTROLS: Unit shall be complete with self-contained low-
voltage control circuit. Safeties shall include compressor over-
temperature and overcurrent.
Heating section shall be provided with the following minimum
protection: High temperature limit switch, induced-draft motor
speed sensor, flame rollout switch, and flame proving controls.
OPTIONS: Factory-installed integrated economizer shall in-
clude all hardware and controls to provide cooling using outdoor
air alone or in conjunction with mechanical cooling. Varislide™
dampers shall be low leakage type, not to exceed 3% leakage
at 1.0 in. wg pressure differential. Economizer shall be capable
of introducing up to 100% outdoor air and shall be equipped
with a barometric relief damper. Economizer controls shall be
dry-bulb (Varislide) or enthalpy (Parablade) type. Damper shall
close on power loss.
Other factory-installed options shall include: 50% manual
outdoor-air damper, controls upgrade kit, and alternate high-
static evaporator-fan motors and/or drives.
APPROVALS: The unit shall be CSA (036-072) or CUL (090-
150) design certified and UL tested and certified. All wiring shall
be in accordance with NEC and units shall meet ASHRAE
standard 62. The unit shall be rated in accordance with ARI
Standards 210/240 or 360 and 270. Units shall be designed to
conform to NRCA standards. Insulation and adhesive shall
meet NFPA 90A requirements for flame spread and smoke
generation.
ACCESSORIES: Field-installed accessories shall include: Roof
curb (14 in. or 24 in.), roof curb electrical and gas utility connec-
tions package, Varislide economizer, manual damper, 25% and
100% two-position outdoor-air dampers, low ambient kit, Time
Guard
ா
II short-cycle circuit protection, LP (liquid propane) con-
version kit, thermostats and subbases, flue hood protector, con-
denser coil hail guard, NO
x
reduction kit, controls upgrade kit,
condenser coil grille, head pressure control, thru-the-bottom
service connectors, condenser coil salt spray protector, hail
guard, fan/filter status switch, flue discharge deflector, enthalpy
control sensor, and enthalpy control.
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