Bryant 581A User Manual
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ENGINEERS’ SPECIFICATION GUIDE
GENERAL: Furnish and install single-package, outdoor rooftop-
mounted, electrically controlled, heating and cooling unit utiliz-
ing reciprocating compressor(s) for cooling and gas combustion
for heating duty. Unit shall discharge supply air vertically or hori-
zontally as shown on the contract drawings.
Nominal unit electrical characteristics shall be
v,
3 ph, 60 Hz. The unit shall be capable of satisfactory operation
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 con-
denser entering air of
F dry bulb. Total design condi-
tions shall be a minimum of
Btuh/Watt.
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(s) shall be of the semi-hermetic
type with crankcase heaters and suitable vibration isolators and
dual independent refrigeration circuits shall be supplied
(180,240).
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 of the 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 belt driven as
shown on the equipment drawings. 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 intermit-
tent 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 fil-
ter drier, fixed orifice feed system, and service gage connec-
tions on suction line, liquid line, and compressor discharge line,
as well as low-pressure and high-pressure protection.
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
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 pres-
sure switch, manual reset 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. Dampers
shall be low leakage type, not to exceed 2% leakage at 1.0 in.
wg pressure differential. Economizer shall be capable of intro-
ducing up to 100% outdoor air and shall be equipped with a
gravity relief damper. Economizer controls shall be dry-bulb
type.
On all units where the factory-installed economizer is not cho-
sen, the factory-installed manual outdoor-air damper shall be
included.
APPROVALS: The unit shall be ETL, Canada design certified
and ETL 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 Standard 360. Units shall
be designed to conform to NRCA standards. Insulation and ad-
hesive shall meet NFPA 90A requirements for flame spread and
smoke generation.
ACCESSORIES: Field-installed accessories shall include: Hori-
zontal and vertical roof curbs (14 in. or 24 in.), horizontal
adapter, economizer, two-position damper, low-ambient kit,
Time Guard
ா
II short-cycle circuit protection, thermostat and
subbase, barometric relief damper, power exhaust, head pres-
sure control device, winter start time-delay relay, and enthalpy
control sensor.
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