Product data

81
Packaged Rooftop Air-to-Air Heat Pump
with Electric Heat Option — Constant
Volume Application
HVAC Guide Specifications
Size Range: 3 to 10 Tons, Nominal Cooling
Carrier Model Number: 50TFQ
Part 1 — General
1.01 SYSTEM DESCRIPTION
Outdoor rooftop- or slab-mounted, electrically con-
trolled air-to-air heat pump utilizing a hermetic com-
pressor for heating and cooling duty. Unit shall
discharge supply air vertically or horizontally as
shown on contract drawings.
1.02 QUALITY ASSURANCE
A. Unit shall be rated in accordance with ARI Stan-
dards 210/240 and 270.
B. Unit shall be designed to conform to ASHRAE 15,
latest revision, and in accordance with UL 1995.
C. Unit shall be UL tested and certified in accordance
with ANSI Z21.47 Standard and UL listed and certi-
fied under Canadian Standards as a total package
for safety requirements.
D. Roof curb shall be designed to conform to NRCA
Standards.
E. Insulation and adhesive shall meet NFPA 90A
requirements for flame spread and smoke
generation.
F. Unit casing shall be capable of withstanding Federal
Test Method Standard No. 141 (Method 6061)
500-hour salt spray test.
1.03 DELIVERY, STORAGE, AND HANDLING
Unit(s) shall be stored and handled per manufac-
turer’s recommendations.
Part 2 — Products
2.01 EQUIPMENT (STANDARD)
A. General:
Factory-assembled, single-piece air-to-air heat
pump. Contained within the unit 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 be constructed of galvanized
steel, bonderized and coated with a baked
enamel finish on all externally exposed surfaces
with primer coated internal panels.
2. Indoor fan cabinet interior shall be insulated
with a minimum
1
/
2
-in. thick flexible fiberglass
insulation coated on the air side.
3. Cabinet panels shall be easily removable for
servicing.
4. Holes shall be provided in the base rails for rig-
ging shackles to facilitate overhead rigging, and
forklift slots shall be provided to facilitate
maneuvering.
5. Unit shall have a factory-installed, sloped con-
densate drain pan made of a non-corrosive
material, providing a minimum
3
/
4
-in. connec-
tion with both vertical and horizontal drains and
shall comply with ASHRAE 62.
6. Unit shall have factory-installed filter access
panel to provide filter access with tool-less
removal.
7. Unit shall have standard thru-the-bottom power
connection capability.
C. Fans:
1. Indoor blower shall be of the direct- or belt-
driven, double inlet, forward-curved centrifugal
type. Belt drive shall include an adjustable-pitch
motor pulley.
2. Indoor blower shall be made from steel with a
corrosion-resistant finish and shall be dynami-
cally balanced.
3. Bearings shall be of the sealed, permanently
lubricated, ball-bearing type for longer life and
lower maintenance.
4. Outdoor fan shall be of the direct-driven propel-
ler type and shall discharge air vertically.
5. Outdoor fan shall have aluminum blades riveted
to corrosion-resistant steel spiders and shall be
dynamically balanced.
D. Compressor(s):
1. Fully hermetic type, internally protected.
2. Factory rubber shock-mounted and internally
spring mounted for vibration isolation.
E. Coils:
1. Outdoor and indoor coils shall have aluminum
plate fins mechanically bonded to enhanced
copper tubes with all joints brazed.
2. Tube sheet openings shall be belled to prevent
tube wear.
3. Indoor coil shall be of the face split design.
4. Coils:
a. Copper-fin coils shall be constructed of cop-
per fins mechanically bonded to copper
tubes and copper tube sheets. Galvanized
steel tube sheets shall not be acceptable. A
polymer strip shall prevent coil assembly
from contacting the sheet metal coil pan to
minimize potential for galvanic corrosion
between coil and pan. All copper construc-
tion shall provide protection in moderate
coastal environments.
b. E-Coated aluminum-fin coils shall have a
flexible epoxy polymer coating uniformly
applied to all coil surface areas without
material bridging between fins. Coating pro-
cess shall ensure complete coil encapsula-
tion. Color shall be high gloss black with
Guide specifications — 50TFQ units
50TFQ004-01250TFQ004-012