Engineers' Specification Guide - Bryant 542F Manual

GENERAL: Furnish and install a self-contained, air-to-air elec-
tric heat pump rooftop unit with supply- and return-air connec-
tions off the bottom of the unit, mounted on a full perimeter, field-
assembled roof curb. The rooftop unit shall be completely
factory-assembled and tested, and shall include compressors,
indoor coil, outdoor coil, fans and motors, interconnecting wir-
ing, prewired control panel, filters, and other necessary compo-
nents mounted in a corrosion-resistant all-weather cabinet. Unit
shall be shipped fully charged with oil and R-22 refrigerant.
COOLING CAPACITY: Total net cooling capacity of the unit
shall be Btuh or greater, and sensible capacity shall be
Btuh or greater at conditions of
tor entering air of 67 F wet bulb, 80 F dry bulb, and condenser
entering air temperature of 95 F dry bulb. Equipment must have
an EER of 8.5 or higher at this condition.
HEATING CAPACITY: Total heating capacity shall be
Btuh or greater (integrated rating) when rated at
F dry bulb outdoor ambient with
F air entering indoor (heating) coil. The equipment must
have a minimum heating COP of 3.0 at 47 F dry bulb outdoor
ambient (high temp) and 2.1 at 17 F dry bulb outdoor ambient
(low temp). Supplemental heat of
to satisfy heat loss at winter design conditions. The coefficient of
performance (COP) must be 2.9 or better at 47 F.
CABINET: The cabinet shall be constructed of heavy-gage zinc-
coated galvanized steel with baked enamel finish. This finish
shall exceed the U.S. Army Corps of Engineers standards with-
out peeling, cracking, or rusting beyond
when subjected to 5% salt spray solution at 95 F for 1000 hours.
The cabinet shall be constructed such that one-piece top is
used for the entire indoor air-handling section to ensure water-
tightness. Two-in. replaceable filters mounted internally shall be
supplied.
COMPRESSORS: Compressors shall be of the serviceable,
semi-hermetic type, with crankcase heaters and suitable vibra-
tion isolators. A separate refrigerant circuit shall be provided for
each compressor. An automatic resetting circuit shall be pro-
vided to prevent rapid compressor cycling.
OUTDOOR SECTION: The outdoor coil shall be constructed of
aluminum plate fins mechanically bonded to seamless copper
tubes. Outdoor fans shall be direct-driven, slow-speed propeller
type for quiet operation and shall be mounted for vertical dis-
charge. The outdoor motors shall be protected as required by
NEC and be supplied with rainshields.
Bryant
Air Conditioning
Copyright 1995 Carrier Corporation
ENGINEER'S SPECIFICATION GUIDE
3
ft /min evapora-
3
ft /min and
kW shall be provided
1 ⁄ in. on a scratch mark
8
INDOOR SECTION: Indoor coil shall be constructed of alumi-
num plate fins mechanically bonded to seamless copper tubes.
Indoor blower shall be of centrifugal type, forward curved. The
blower shall be belt-driven by means of an adjustable pitch pul-
ley, permitting a variation of airflow by means of blower speed
adjustment. Blower motor shall be electrically protected as re-
quired by NEC. Blower motor shall be mounted on the adjust-
able base, allowing for proper alignment and tension. The steel
shaft shall rotate in prelubricated bearings.
CONTROL CIRCUIT: The unit control panel shall be prewired in
the unit casing furnished with a 24-v control transformer, high-
and low-pressure switches, compressor, outdoor and indoor fan
motor contactors, as well as other protective devices. The de-
frost circuit shall be time and temperature initiated. A
90-minute timer shall energize the defrost cycle only if the coil
temperature indicates a frost condition. Defrost shall terminate
after 10 minutes of operation, or when a satisfactory coil tem-
perature is achieved to minimize defrost operating time.
APPROVALS: The unit shall be ETL tested and certified. All wir-
ing shall be in accordance with NEC, and units shall meet
ASHRAE Standard 62. The unit shall be rated in accordance
with ARI Standard 340. Units shall be designed to conform to
NRCA standards. Insulation and adhesive shall meet NFPA 90A
requirements for flame spread and smoke generation.
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
introducing 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 in-
cluded. In addition, a factory-installed alternate indoor-fan drive
is available.
ACCESSORIES: Field-installed accessories shall include:
Economizer, vertical and horizontal roof curbs (14 or 24 in.),
horizontal adapter, two-position damper, Time Guard
cycle circuit protection, thermostats and subbases, electric
heaters, barometric relief damper, power exhaust, emergency
heat, remote control panel, and head pressure control device.
SPECIFICATIONS SUBJECT TO CHANGE WITHOUT NOTICE
Printed in U.S.A.
UNIT MUST BE INSTALLED IN ACCORDANCE
WITH INSTALLATION INSTRUCTIONS
5/95 CATALOG NO. BY-3254-205
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