ENGINEERS’ SPECIFICATION GUIDE — MODELS 559F180-300 (15 TO 25 TONS)
GENERAL: Furnish and install single-package, outdoor rooftop-
mounted, electrically controlled cooling unit utilizing reciprocat-
ing compressor(s) for cooling. Unit shall discharge supply air
vertically or horizontally as shown on the contract drawings.
Nominal unit electrical characteristics shall be
v,
3 phase, 60 Hz. The unit shall be capable of satisfactory opera-
tion within voltage limits of
vto 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 evapo-
rator air entering 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.
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 shall have spring vibration iso-
lators and dual independent refrigeration circuits (216-300).
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. Motor bearings shall be
sealed, permanently lubricated, ball-bearing type.
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 throwaway fiberglass 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.
APPROVALS: The unit shall be ETL and ETL Canada tested
and certified. All wiring shall be in accordance with NEC, and
units shall meet ASHRAE Standard 62. The unit (except 300)
shall be rated in accordance with ARI Standards 360 and 270.
Units shall be designed to conform to NRCA standards. Insula-
tion 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
included.
ACCESSORIES: Field-installed accessories shall include:
Economizer, roof curbs (14 or 24 in.), horizontal adapter, two-
position damper, low ambient kit, short cycle circuit protection,
thermostats and subbases, enthalpy control sensor, winter start
time-delay relay, electric resistance heaters, barometric relief
damper, power exhaust, and head pressure control device.
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