Bryant 581C - Manual (Page 285)

285
GUIDE SPECIFICATIONS — 581A210-300 UNITS
PACKAGED ROOFTOP ELECTRIC COOLING UNIT WITH
GAS HEAT — CONSTANT VOLUME APPLICATION
HVAC GUIDE SPECIFICATIONS
SIZE RANGE: 18 TO 25 TONS NOMINAL (COOLING)
250,000 TO 400,000 BTUH, NOMINAL
(INPUT HEATING)
BRYANT MODEL NUMBERS: 581A
PART 1 — GENERAL
1.01 SYSTEM DESCRIPTION
Unit is an outdoor rooftop mounted, electrically controlled
heating and cooling unit utilizing scroll hermetic compres-
sors with crankcase heaters for cooling duty and gas com-
bustion heat for heating duty. Supply air shall be
discharged downward or horizontally, as shown on con-
tract drawings.
1.02 QUALITY ASSURANCE
A. Unit shall well exceed the energy efficiency requirements
of ASHRAE standard 90.1-2001. Unit shall be Energy
Star qualified.
B. Unit shall be rated in accordance with ARI Standards 270
and 360 and all units shall be designed in accordance
with UL Standard 1995.
C. Unit shall be designed to conform to ASHRAE 15.
D. Unit shall be UL and UL, Canada, tested and certified in
accordance with ANSI Z21.47 Standards as a total
package.
E. Roof curb shall be designed to conform to NRCA
Standards.
F. Insulation and adhesive shall meet NFPA 90A require-
ments for flame spread and smoke generation.
G. Unit casing shall be capable of withstanding 500-hour salt
spray exposure per ASTM B117 (scribed specimen).
H. Unit shall be manufactured in a facility registered to
ISO 9001:2000.
1.03 DELIVERY, STORAGE, AND HANDLING
Unit shall be stored and handled per manufacturer’s
recommendations.
PART 2 — PRODUCTS
2.01 EQUIPMENT (STANDARD)
A. General:
The 581A unit shall be a factory assembled, single-piece
heating and cooling unit. Contained within the unit enclo-
sure shall be all factory wiring, piping, controls, refrigerant
charge (R-22), and special features required prior to field
start-up.
B. Unit Cabinet:
1. Constructed of galvanized steel (G90 — 1.8 oz. of
zinc per square foot of sheet metal), bonderized and
primer-coated on both sides and coated with a baked
polyester thermosetting powdercoating finish on the
outer surface. The color of this pre-painted steel is
referred to as “American Sterling,” a gray color. Bry-
ant’s paint specification for this color is PH184.
Color: American Sterling, this gray color is to match
federal standard 595a, #26231.
Gloss (per ASTM 0523, 60 deg. F): 60.
Hardness of paint film: H-2H pencil hardness.
2. Indoor blower compartment interior surfaces shall be
insulated with a minimum 1 /
2
-in. thick, 1 lb density
fiberglass insulation. Fiberglass insulation shall be
bonded with a thermosetting resin (8 to 12% by
weight nominal, phenol formaldehyde typical), and
coated with an acrylic or other material that meets
the NFPA 90 flame retardance requirements and
has an ‘‘R’’ Value of 3.70. Aluminum foil-faced fiber-
glass insulation shall be used in the gas heat
compartment.
3. Cabinet panels shall have minimum 1 /
2
-in. thick,
1.5-lb. density insulation. Each external access panel
shall be permanently attached to the rooftop unit.
Panels shall also include tiebacks.
4. Filters shall be accessible through an access panel.
5. Holes shall be provided in the base rails (minimum
14 gage) for rigging shackles and level travel and
movement during overhead rigging operations.
6. Fork lift slots shall be available from two sides of the
unit (end and side).
7. Unit shall contain a sloped drain pan, to prevent
standing water from accumulating. Pan shall be fabri-
cated of epoxy powder coated steel.
C. Fans:
1. Indoor blower (evaporator fan):
a. Centrifugal supply air blower shall have pillow-
block ball bearings and adjustable belt
drive. Blower assembly shall slide out of unit for
servicing.
b. Fan wheel shall be made from steel with a corro-
sion resistant finish. It shall be a dynamically bal-
anced, double-inlet type with forward-curved
blades.
c. The indoor fan system (blower wheels, motors,
belts, and both bearings) shall slide out for easy
access.
2. Condenser fans shall be of the direct-driven propeller
type, with corrosion-resistant blades riveted to corro-
sion-resistant steel supports. They shall be dynami-
cally balanced and discharge air upwards.
Condenser fan motors shall be totally enclosed and
be of a shaft down design.
3. Induced-draft blower shall be of the direct-driven, sin-
gle inlet, forward-curved, centrifugal type. It shall be
made from steel with a corrosion-resistant finish and
shall be dynamically balanced.
D. Compressor(s):
1. Fully hermetic, scroll type, internally protected.
2. Factory spring-shock mounted and internally spring
mounted for vibration isolation.
3. On electrically and mechanically independent refrig-
erant circuits.
4. Reverse rotation protection capability.
5. Crankcase heaters shall only be activated during
compressor OFF mode.
E. Coils:
1. Standard evaporator and condenser coils shall have
copper or aluminum plate fins mechanically bonded
to seamless internally grooved copper tubes with all
joints brazed.
2. Coils shall be leak tested at 150 psig (1034 kPa) and
pressure tested at 450 psig (3103 kPa).