York ZT SERIES, Техническое руководство

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5167821-YTG-K-1118
Johnson Controls Ducted Systems 14
Guide specifications
General
YORK® Predator
®
units are convertible single packages with a common footprint cabinet and common roof curb for all 3 through
12.5 ton models. The units were designed for light commercial applications and can be easily installed on a roof curb, slab, or
frame. All Predator
®
units are self-contained and assembled on rigid full perimeter base rails allowing for 3-way forklift access and
overhead rigging. Every unit is completely charged with R-410A, wired, piped, and tested at the factory to provide a quick and easy
field installation. All units are convertible between side and down airflow. Independent economizer designs are used on side and
down discharge applications, as well as all tonnage sizes. Predator
®
units are available in the following configurations: cooling
only, cooling with electric heat and cooling with gas heat. Electric heaters are available as factory-installed options or field-installed
accessories.
Description
Units shall be factory assembled, single package, (Elec/Elec, Gas/Elec), designed for outdoor installation. They shall have built in field
convertible duct connections for down discharge supply/return or horizontal discharge supply/return and be available with factory installed
options or field installed accessories. The units shall be factory wired, piped and charged with R-410A refrigerant and factory tested prior to
shipment. All unit wiring shall be both numbered and color coded. The cooling performance shall be rated in accordance with DOE and
AHRI test procedures. Units shall be CSA certified to ANSI Z21.47 and UL 1995/CAN/CSA No. 236-M90 standards.
Unit cabient
Unit cabinet shall be constructed of galvanized steel with exterior surfaces coated with a non-chalking, powder paint finish, certified
at a 750-hour salt spray test per ASTM-B117 standards. Indoor blower sections shall be insulated with up to 1” thick insulation
coated on the airside. Either aluminum foil faced or elastometric rubber insulation shall be used in the unit’s compartments and be
fastened to prevent insulation from entering the air stream. Cabinet doors shall be hinged with toolless access for easy servicing and
maintenance. Full perimeter base rails shall be provided to assure reliable transit of equipment, overhead rigging, fork truck access
and proper sealing on roof curb applications. Disposable 2-in. filters shall be furnished as standard and be accessible through
hinged access door. Fan performance measuring ports shall be provided on the outside of the cabinet to allow accurate air
measurements of evaporator fan performance without removing panels or creating bypass of the coils. Condensate pan shall be
slide out design, constructed of a non corrosive material, internally sloped and conforming to ASHRAE 62-B9 standards.
Condensate connection shall be a minimum of ¾” I.D. female and be rigid mount connection.
Indoor (evaporator) fan assembly
Fan shall be a belt drive assembly and include an adjustable pitch motor pulley. Job site selected brake horsepower shall not exceed
the motors nameplate horsepower rating plus the service factor. Units shall be designed to operate within the service factor. Fan
wheel shall be double inlet type with forward curve blades, dynamically balanced to operate smoothly throughout the entire range of
operation. Design shall meet ASHRAE 90.1 single-zone variable supply air volume standard. Bearings shall be sealed and perma-
nently lubricated for longer life and no maintenance. Entire blower assembly and motor shall be slide out design.
Outdoor (condenser) fan assembly
The outdoor fans shall be of the direct drive type, discharge air vertically, have aluminum blades riveted to corrosion resistant steel spider
brackets and shall be dynamically balanced for smooth operation. The outdoor fan motors shall have permanently lubricated bearings
internally protected against overload conditions and staged independently. A cleaning window shall be provided on two sides of the units
for coil cleaning.
Refrigerant components
Compressors:
a. Shall be fully 2-stage, hermetic type, direct drive, internally protected with internal high-pressure relief and over temperature
protection. The hermetic motor shall be suction gas cooled and have a voltage range of + or – 10% of the unit nameplate
voltage.
b. Shall have internal spring isolation and sound muffling to minimize vibration and noise, and be externally isolated on a
dedicated, independent mounting.
Coils:
a. Evaporator coils shall have aluminum plate fins mechanically bonded to seamless internally enhanced copper tubes with all
joints brazed. Special Phenolic coating shall be available as a factory option.
b. Evaporator coils shall be of the direct expansion, draw-through design.
c. Condenser coils shall have Micro-Channel aluminum tube, aluminum fins.
d. Condenser coils shall be of the draw-through design.