Guide Specifications; System Description - Carrier Performance 50VT Product Data

GUIDE SPECIFICATIONS (CONT)
Packaged Heat Pumps
HVAC Guide Specifications
Size Range: 2 to 5 Tons, Nominal Cooling
Carrier Model Number: 50VT
Part 1⎯General

SYSTEM DESCRIPTION

Outdoor, packaged, air- -to- -air heat pump unit utilizing a hermetic
scroll compressor for cooling duty and optional electric heating.
Unit shall discharge supply air vertically or horizontally as shown
on contract drawings. Outdoor fan/coil section shall have a
draw- -thru design with vertical discharge for minimum sound
levels.
QUALITY ASSURANCE
A. Unit shall be rated in accordance with ARI Standards 210/240
and 270.
B. Unit shall be designed in accordance with UL Standard
1995.
C. Unit shall be manufactured in a facility registered to ISO 9001
manufacturing quality standard.
D. Unit shall be UL listed and c- -UL certified as a total package
for safety requirements.
E. Roof curb shall be designed to conform to NRCA Standards.
F. Insulation and adhesives shall meet NFPA 90A requirements
for flame spread and smoke generation.
G. Cabinet insulation shall meet ASHRAE Standard 62P.
DELIVERY, STORAGE AND HANDLING
Unit shall be stored and handled per manufacturer's
recommendations.
Part 2 ⎯ Products
EQUIPMENT
A. General:
Factory- -assembled, single- -piece, heat pump unit. Contained
within the enclosure shall be all factory wiring, piping, controls,
refrigerant charge (R- -22), and special features required prior to
field start- -up.
B. Unit Cabinet:
1. Unit cabinet shall
zinc- -coated, pre- -painted steel capable of withstanding 500
hours of salt spray.
2. Normal service shall be through a single removable cabinet
panel.
3. The unit shall be constructed on a rust proof unit base that
has an externally trapped, integrated sloped drain.
4. Indoor fan compartment top surface shall be insulated with
a minimum 1/2- -in. (13 mm) thick, flexible fiberglass
insulation, coated on the air side and retained by adhesive
and mechanical means. The indoor wall sections will be
insulated with a minimum semi- -rigid, foil- -faced board
capable of being wiped clean. Aluminum foil- -faced
fiberglass insulation shall be used in the entire indoor air
cavity section.
5. Unit shall have a field- -supplied condensate trap.
6. Metal Insulated Duct Covers for side discharge will be
standard on all sizes.
7. Unit insulation conforms to ASHRAE 62P.
C. Fans:
1. The indoor fan shall be 5- -speed, direct- -drive, as shown on
equipment drawings.
be constructed of phosphated,
2. Fan wheel shall be made from steel and shall be
double- -inlet type with forward- -curved blades with
corrosion resistant finish. Fan wheel shall be dynamically
balanced.
3. Outdoor fan shall be direct- -drive, propeller- -type with
aluminum blades riveted to corrosion resistant steel spiders,
be dynamically balanced, and discharge air vertically.
D. Compressor:
1. Fully hermetic compressors with factory- -installed vibration
isolation.
2. Scroll compressors shall be standard on all units.
3. Compressor Protection:
Defrost control shall protect compressor by preventing
"short cycling."
E. Coils:
Indoor and outdoor coils shall have aluminum plate fins
mechanically bonded to seamless copper tubes with all joints
brazed. (Copper/copper and vinyl- -coated construction available
as option.) Tube sheet openings shall be belled to prevent tube
wear.
F. Refrigerant Metering Device:
Refrigerant metering device shall be thermostatic expansion
valve for cooling, and fixed orifice for heating.
G. Filters:
Filter section shall consist of field- -installed, throwaway, 1- -in.
(25 mm) - - thick fiberglass filters of commercially available
sizes.
H. Controls and Safeties:
1. Unit controls shall be complete with a self- -contained, low- -
voltage control circuit.
2. Units shall incorporate an internal compressor protector that
provides reset capability.
I. Operating Characteristics:
1. Unit shall be capable of starting and running at 125_F
(51.7_C) ambient outdoor temperature.
2. Compressor with standard controls shall be capable of
operation down to 40_F (4.4_C) ambient outdoor
temperature in cooling mode.
3. Unit shall be provided with 60- -second fan time delay after
the thermostat is satisfied.
J. Electrical Requirements:
All unit power wiring shall enter the unit cabinet at a single
location.
K. Motors:
1. Compressor motors shall be of the refrigerant- -cooled type
with line- -break thermal and current overload protection.
2. All fan motors shall have permanently lubricated bearings,
and inherent, automatic reset, thermal overload protection.
3. Condenser fan motor shall be totally enclosed.
L. Special Features Available:
1. Louvered Grille:
Wire grille shall be standard on all units. Louvered grille
shall be available as a factory- -installed option to provide
hail guard and vandalism protection.
2. Coil Options:
Shall include factory- -installed optional copper/copper and
vinyl- -coated refrigerant coils.
3. Economizer:
a. Economizer controls capable of providing free cooling
using outside air.
b. Equipped with low leakage dampers not to exceed 3%
leakage, at 1.0 in. wc pressure differential.
c. Spring return motor shuts off outdoor damper on power
failure.
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